BE832342A - PRODUCTION AND APPLICATION OF IMPROVED PHENOL-ALDEHYDE RESOLS - Google Patents

Description

       

  The present invention relates to the field of

  
condensation, catalyzed by a base, which is obtained at

  
from a phenol and an aldehyde such as, in particular,

  
phenol-formaldehyde resols. In one aspect, the invention relates to

  
condensation products having better stability against loss of reactivity when maintained under aging conditions which would otherwise be adverse to them.

  
According to another particular aspect, the invention relates to liquid condensation products which, in addition to a possible extended storage period, are particularly suitable for the formation of cellular phenolic resins.

  
It is known in practice that the condensation of a phenol and

  
of an aldehyde gives materials which can yield on hardening

  
  <EMI ID = 1.1>

  
lysed with a base, using at least a stoichiometric amount

  
approximately one aldehyde yields condensation products known as resols, while acidic catalysts and the use of insufficient aldehyde yields.

  
novolacs. Liquid resols and solid resols all have

  
They have the characteristic of being able to harden when hot to give

  
infusible, fully crosslinked products, without the need to add a crosslinking agent for this. At this point

  
view, we can more descriptively designate the resols as

  
being phenolic resins obtained in a single stage, unlike novolacs which are resins obtained in two stages

  
and which require the addition of a crosslinking agent for the curing process The reactivity of the resoles and their suitability

  
to a self-condensation giving resins to. molecular weight

  
higher are due to the presence of hydroxy groups &

  
methyls which bind to the aromatic phenolic nucleus during

  
condensation catalyzed by a base.

  
the hardening of the resols to give thermic resins

  
  <EMI ID = 2.1>

  
with a release of heat and it is accelerated by materials

  
acids. In the presence of strongly acidic accelerators of the exothermic reaction and a source of a swelling action, the

  
Liquid resols quickly harden to cellular phenolic resins. Phenolic foams are used to contain flower arrangements and for general packaging purposes. However, they do not have the field of very diverse industrial applications reached by cellular polyurethane. Compared to cellular polyurethanes, phenolic foams have remarkable inherent resistance to combustion with a free flame, and they emit very little smoke when heated. Therefore, more attention is being focused on phenolic resins for various applications where fire poses a particular risk. In addition to improving certain

  
  <EMI ID = 3.1>

  
brilliant or incandescent red but without visible flame), it is also necessary to overcome certain drawbacks associated with raw resols such as, in particular, their mediocre possible shelf life. From the point of view of industrial application, the most important resols are those originating from the phenol itself and from formaldehyde.

  
As generally described in the literature, the formation of phenol-formaldehyde resols involves the condensation of phenol with at least an approximately equimolar amount of

  
  <EMI ID = 4.1>

  
calin, and treating the condensation products with an acid, such as sulfuric acid, to neutralize the alkaline catalyst. Depending on the final application of the resole product, the water content of the product neutralized from this condensation can be added at a predetermined level, by dilution or by dehydration. If an alkali metal hydroxide is used as a catalyst, it may be necessary to filter the condensation product to remove the precipitated salts formed during neutralization, depending on the water content and the end application. of the product resolution. Whether or not the neutralized condensation product is filtered, alkali metal salts are present in this product.

  
In any case, during the industrial manufacture of phenol-formaldehyde resols, supplied in the form of foamable resins,

  
filtration is avoided by the use of barium hydroxide as a catalyst, which, when neutralized with sulfuric acid, forms a salt which does not separate by precipitation and

  
that remains in the product.

  
  <EMI ID = 5.1>

  
not been elucidated. However, it is generally accepted that they contain varying amounts of mono-nuclear mono-nuclear phenols.

  
  <EMI ID = 6.1>

  
polymethylol poly-nuclear. Methylol groups are activated by the presence of phenolic hydroxyl groups and, therefore, conventional resols undergo easy self-condensation, even at room temperature, which contributes to their poor shelf life.

  
The problem of resole instability has been around for a long time and is associated with the phenol-formaldehyde resols available on an industrial scale. It is particularly important for liquid, low water content resols supplied

  
  <EMI ID = 7.1>

  
its categories of liquid resols are employed by the manufacturer of the foams in a relatively short period of time after the preparation of these resols, these gradually lose their initial reactive nature of thermosets.

  
For example, resols for making phenolic foam

  
  <EMI ID = 8.1>

  
as foamable horn positions after about 4 weeks of

  
gasoline, or even less, at ordinary room temperatures

  
  <EMI ID = 9.1>

  
Gressive reactivity during storage prevents standardization or homogenization of the formulations of the foams, which would make it possible to obtain as products foams having predetermined specifications, such as the density of this foam. In order to slow their tendency to progress to a higher molecular weight and a less reactive form, such resols, intended for the manufacture of a rigid phenolic foam of medium to high density, are maintained at lower temperatures.

  
  <EMI ID = 10.1>

  
refrigerate them often during storage and shipping. Of course, the installation and maintenance of refrigeration or cooling equipment at the site of the foam plant, for storage, is an onerous and inconvenient obligation.

  
Other resoles available on an industrial scale are intended for the manufacture of a very low density foam. <EMI ID = 11.1>

  
significantly higher in free phenol which generally ranges from about 20 to about 40% by weight. Such particular resols are indicated as being shoppable for periods

  
  <EMI ID = 12.1>

  
to retain their good foaming abilities, the resol manufacturers recommend that they be kept at temperatures below 21 [deg.] C and to avoid prolonged storage. Due to their very highly reactive nature in the presence of the acid catalysts of conventional foam formulations, foaming must be carried out at a temperature below room temperature in order to control the curing process and in order to obtain a product of satisfactory quality. Therefore, such resols are usually mixed with other less reactive materials, or these resols can be used as such for the application, by spraying, of the phenolic foam.

  
It is desirable, and it is a primary object of the present invention, to provide condensate products.

  
  <EMI ID = 13.1>

  
) aldehyde, in particular phenol-formaldehyde resols, having better aging characteristics.

  
Another object is to provide resols which, in addition to a possible prolonged storage time, are particularly useful for obtaining cellular phenolic products.

  
Yet another object is to provide phenolformaldehyde resols which substantially retain their reactivity as foamable compositions during prolonged storage at ambient conditions and which are capable of foaming to give cellular phenolic products of which the density can drop.

  
  <EMI ID = 14.1>

  
foaming when pouring in place.

  
Another object is to provide a method for producing resols having the above characteristics.

  
Various other objects and advantages of the present invention will become apparent to those having ordinary experience in this field upon study of the description and disclosure which follows.

  
According to one aspect of the present invention, there is provided phenolic resins having no ionic bodies removable by the free acid form of a cation exchange resin and by the free base form of an ion exchange resin. anions.

  
The compositions of the invention, and in particular the resols

  
  <EMI ID = 15.1>

  
advantageous in forming cellular phenolic products comprising medium to high density phenolic foam as well as low density foam (between about 8 g

  
  <EMI ID = 16.1>

  
with payment in place. the resols of the invention also have a sufficiently high reactivity to allow their use in the formation of a very low density foam.

  
  <EMI ID = 17.1>

  
It has been found that the deionized resols of the invention possess a very interesting and unexpected association.

  
of properties. One of these properties is their inherent stability.

  
  <EMI ID = 18.1>

  
described above serving in industrial practice. One manifestation of the greater inherent stability of the resols of the invention is their long shelf life. As it is used in the context of the present invention., The expression

  
"storage" or "storage in store" means the period of aging (aging accelerated by heat or aging).

  
  <EMI ID = 19.1>

  
given resol substantially retains its initial compositional reactivity. soft sand. Reactivity is the rate at which polymer foam forms when the resole is subjected to acid catalysis, and this reactivity is reflected in the duration of the polymerization reaction (e.g., the time to formation of a cream and the rising time) and, in particular, in the density of the foam produced. In sharp contrast to the poor storage or aging capability of the industrial resols described above, having specifications intended for the production of a medium to high density foam, the resols of the invention, which are suitable for darkening.

  
  <EMI ID = 20.1>

  
reactivity of foamable compositions for longer periods of time at ordinary room temperatures

  
  <EMI ID = 21.1> refrigeration before use. The better inherent stability of the deionized resols of the invention is also reflected in the observation that the period of time over which these resols polymerize to achieve a gel state, as opposed to the thermoset and fully cured state, is also longer than the period of time leading to the gel point of conventional resols.

  
Another indicator of the greater inherent stability of the resols of the invention to self-condensation giving less reactive forms is the lower rate of water accumulation during prolonged standing, Thus, while the aforementioned highly active resols, commercially available and specified for the formation of a very low density foam, have a reasonably good possible shelf life, their water content increases at a rate significantly greater than that observed for the resols of the invention.

  
Another characteristic of the resols of the invention is that, despite their greater inherent stability and their thus prolonged storage possibility, they have a greater reactivity of foamable compositions when subjected to the action of acid catalysts. A manifestation of their very great

  
  <EMI ID = 22.1>

  
foam of a given density than the amount otherwise required in the case of a conventional phenolic resin foam.

  
  <EMI ID = 23.1>

  
vention is that the significant increase in viscosity that is observed during aging is not accompanied by a corresponding loss of their reactivity of foamable compositions.

  
accompanying figures 1, 2 and 3 show the effect of hot aging on the viscosity of resols and on the density of the foam obtained (figure 1, where the abscissas

  
  <EMI ID = 24.1>

  
aging at ambient conditions on the water content
(figure 2; abscissa: period of aging at ambient conditions; ordinate: water content,% by weight) and on viscosity (figure 3 abscissa: period of aging at ambient conditions).

  
  <EMI ID = 25.1> <EMI ID = 26.1>

  
that one. employed in industrial practice. These figures, and the data on which they are based, are discussed in the

  
  <EMI ID = 27.1>

  
gures 2 and 3) below.

  
According to another aspect of the teachings of the present invention, the latter provides liquid phenolic resols, having the best possible shelf life, which are obtained by the process according to which deionization of the liquid condensation product formed by the reaction, catalyzed by an alkali metal, of a phenolic compound and an aldehyde, by the treatment of this product with the free acid form of a cation exchange resin and with the free base form of a resin of anion exchange. the present process is particularly advantageously applied to liquid phenol-formaldehyde condensation products which have been formed in the presence of a catalyst derived from an alkali metal, such as hydroxides, oxides, carbonates and bicarbonates of any alkali metal

  
  <EMI ID = 28.1>

  
are the hydroxides of lithium, sodium, potassium, rubi-

  
dium, cesium, francium, barium, calcium and magnesium, as well as potassium and sodium carbonates and bicarbonates, calcium oxide etc. The process is described with particular reference to condensation products of phenol and formaldehyde. However, this method is also applicable

  
to condensation products of other phenolic compounds and other aldehydes.

  
the excellent shelf life and the excellent aging characteristics of new resole compositions, obtained under the influence of the catalysis of a

  
  <EMI ID = 29.1>

  
presence of ionic bodies which respond to the removal effected by the aforementioned ion exchange resins, which belong to two types. The first type is a cation exchange resin

  
  <EMI ID = 30.1>

  
an exchange potential with alkali metal cations introduced on the phenol-formaldehyde condensation product as

  
  <EMI ID = 31.1>

  
The exchange resin are present as strongly acidic groups such as sulfonic acid groups (-SO &#65533; H) or as weakly acidic groups (-COOH). Preferably, the cation exchange resin is of the strongly acidic variety. The particular polymer structure to which the cation exchange groups are attached is not fundamental to obtaining the new compositions of the present invention. Examples of suitable strong cation exchange resins are resins.

  
  <EMI ID = 32.1>

  
phenol-formaldehyde having sulfonic acid groups, benzene-formaldehyde resins having acid groups

  
  <EMI ID = 33.1>

  
the market by several companies under various trademarks For example, the series of sulfonated copolymers of styrene and livinyl-benzene, available under the respective designation of

  
"Amberlite 200", "Amberlite 200C", "Amberlite IR-120", "Amberlite IR-122", "Amberlite IR-124" and "Amberlite XE-100" from Rohm & Haas Company. fits well. Other suitable strongly acidic cation exchange resins are sold by The Dow Chemical Company under the designation "Dovex 50-W" and by the Diamond Shamrock Company under the designation "Duolite C-3" and "Duolite C-25. ". Illustrative examples of weakly acidic cation exchange resins are crosslinked acrylic polymers and copolymers of acrylic acid and divinyl-benzene, available under the respective designations of "Amberlite IRC-84" and "Amberlite.

  
  <EMI ID = 34.1>

  
Some of the cation exchange resins described above are sold as salts. Therefore, prior to using them in accordance with the teachings of the present invention, these resins are treated to transform the ion exchange groups into the free acid form. This is easily done with the help of a mineral acid like sulfuric acid or hydrochloric acid etc. Usually an excess of the acid is used. The excess acid is then removed with water or with a. suitable solvent for removing liberated salts. The used resin is regenerated in a similar fashion.

  
The new resols of the invention are also free of anions capable of being removed by an anion exchange resin in its free base form, that is to say in a form comprising hydroxyl groups or groups. free amino. The resin can be in strongly basic or weakly basic form. Resins of the strongly basic variety are usually

  
  <EMI ID = 35.1>

  
IRA-400 ". Prior to use in accordance with the teachings of the present invention, these strongly basic anionic resins are treated with an alkaline substance, such as aqueous solutions of an alkali metal hydroxide, to replace them. chloride anions with free hydroxyl and thus form the radical

  
  <EMI ID = 36.1>

  
  <EMI ID = 37.1>

  
resin with water to remove salts of the chloride type. Weakly basic anion exchange resins having polyamine functions linked to a matrix or matrix

  
  <EMI ID = 38.1>

  
than crosslinked, are also suitable. These resins are available in the free base form from Rohm & Haas Company under the

  
  <EMI ID = 39.1>

  
and "Amberlite IRA-68". when these various anion exchange resins become used up, they are easily regenerated by treatment with a strong alkaline substance (for example a solution.

  
  <EMI ID = 40.1>

  
provide the hydroxyl groups again or, in the case of the weakly basic variety, to remove the salts from the amino functions.

  
When using the above-described ion exchange resins in the process of the present invention, the ion exchange operation can be carried out batchwise or continuously. In either procedure, the product of the alkaline condensation of phenol and formaldehyde can be deionized by treating this product with the two different types of ion exchange resins, arranged as a mixed bed.

  
or as single beds. In a mixed bed operation, the alkaline condensation product is brought into intimate contact with the exchange resin until the pH of the treated liquid stabilizes substantially at a value between about 4 and about 7, this which indicates essentially complete deionization.

  
When performing the ion exchange reactions using individual resin beds, the alkaline condensation product is brought into intimate contact with the cation exchange resin in its free acid form for a residence time sufficient to lower the temperature. pH of the condensation product subjected to this treatment at a value between about 1.5 and about 4. Preferably, the treatment is carried out until the pH stabilizes substantially at a particular value within this range. Usually, the pH stabilizes at a value under

  
  <EMI ID = 41.1>

  
essentially complete removal of cations. The cation exchanged liquid is then brought into intimate contact with the firm free base of the anion exchange resin for a residence time sufficient to raise the pH to a value between about 4 and about 7. Preferably, the anion exchange treatment is carried out until the pH remains substantially stable at a particular value within this range. Usually the pH stabilizes at a value within

  
  <EMI ID = 42.1>

  
essentially complete removal of anions.

  
By "substantial stabilization" of the pH at a particular value lying within the respective ranges mentioned above is meant a state in. which the pH fluctuation is not more than about + 0.3-

  
In a batch operation, when using a mixture of cation and anion exchange resins or a successive treatment of the alkaline condensation product with these respective ion exchange resins, intimate contact is easily effected by stirring of a suspension of the resins in the liquid condensation product, by any suitable means, When the pH is brought to a value within the aforementioned ranges,

  
the liquid condensation product and the exchange resins are separated by conventional techniques for separating a liquid and the solids such as decantation or filtration. When the deionization is carried out in successive operations, the liquid condensation product is initially treated with the exchange resin.

  
cations and, since the cation-exchanged material is acidic and has not yet been de-anionized, such separation and passage of the liquid to the anion-exchange processing stage must also take place. as quickly as possible to minimize the residence time in the acid solution and thereby prevent polymerization.

  
In continuous operation, the ion exchange resins are conveniently contained in the same columns or in different columns. The flow of the condensation product in the column (s) can be in any direction, although the liquid condensation product is usually passed downwardly through the exchange resins. The flow rate is adjusted to. through the resins in order to obtain

  
  <EMI ID = 43.1>

  
cations and the anion exchange resin, or of the mixed bed comprising these resins, having a pH lying within the aforementioned respective ranges. Usually the flow rate is between about
320 g and approximately 800 g of condensation product per minute per

  
  <EMI ID = 44.1>

  
flow rate required for any given deionization, in order to obtain accurate pH values, may be higher or lower

  
and that it is governed by various factors such as the particle size of the ion exchange resin, the size of the ion exchange bed, the viscosity of the liquid condensation product to be treated, the concentration of the catalyst at alkali metal base used

  
  <EMI ID = 45.1>

  
changes ions. The required values for flow or recycle are easily determined by sampling the effluent from the respective columns to measure the pH thereof. If the pH responds to the addition of an ion exchange resin
(i.e. if the pH is not substantially stable), the effluent can be recycled to the resin bed or the effluent can be adjusted.

  
  <EMI ID = 46.1>

  
essentially complete sation.

  
The ion exchange reactions are carried out at temperatures

  
  <EMI ID = 47.1>

  
fit very well. The application of heating from an external source is usually avoided, temperatures above room temperature being simply obtained by <EMI ID = 48.1>

  
the introduction of a hot product of condensation into the system

  
  <EMI ID = 49.1>

  
fundamental effect on ion exchange reactions. While atmospheric pressure appears to be most suitable, increased or reduced pressures can also be used as desired. When operating with one or more columns, it may be necessary to have a slightly greater inlet pressure to overcome the pressure drop within any given column, depending on the resistance to the flow and depending on whether or not the bed of the exchange resin is tight.

  
The excellent characteristics of the possible storage time and aging of the resols of the invention are

  
  <EMI ID = 50.1>

  
ionic or ionic which respond to removal by the ion exchange resins described above. the state of deionization and the absence of these ionic bodies exist when the concentration

  
The cation and anion cation has been reduced to a level low enough that the pH of the ion-exchanged resin remains substantially constant in the presence of the respective cation-exchange and anion-exchange resins described herein.

  
The cations which are removed from the resole during the cation exchange reaction include metal cations corresponding to those of the alkali metal catalyst employed in the condensation reaction. By treating the condensation products until the pH stabilizes sensi-

  
  <EMI ID = 51.1>

  
about 4 and preferably between about 2 and about 3.5, the cation content of the. alkali metal from catalyst

  
  <EMI ID = 52.1>

  
that is, less than about 100 parts per million, based on the weight of the condensation product and as determined by emission spectroscopy. It should be understood, however, that other metal cations, the nature of which is unknown, can

  
  <EMI ID = 53.1>

  
in phenol, in formaldehyde or in the catalyst or from the reactor) and that these other cations could also have an adverse effect on the possible storage time of the resole if these cations were not otherwise removed.

  
The nature of the anions which are removed during the anion exchange reaction has not been elucidated. However, it is believed that such anions can be derived from formic acid or benzoic acid. It should be understood, however, that other theories may also explain the finding that unless the cation-exchanged resole is subjected to anion-exchange treatment to a pH in the range of the above-mentioned range of between about 4 and about 7 and preferably up to a pH of about 4.5 to about 6.5, the maximum stability of the resole against irreversible self-condensation is not obtained during aging.

  
It is believed that phenol-formaldehyde resols. deionized of the invention comprise a complex assortment of bodies of the following types:

  

  <EMI ID = 54.1>


  

  <EMI ID = 55.1>
 

  
which is used in industrial practice. These figures, and the data on which they are based, are discussed in the context of Examples 34 and 35 (Figure 1) and Example 45 (Figures 2 and 3) below.

  
According to another aspect of the teachings of the present invention, the latter provides liquid phenolic resols, having the best possible shelf life, which are obtained by the process according to which deionization of the liquid condensation product formed by the reaction, catalyzed by an alkali metal, of a phenolic compound and an aldehyde, by the treatment of this product with the free acid form of a cation exchange resin and with the free base form of a resin of anion exchange. the present process applies particularly advantageously to liquid condensation products

  
  <EMI ID = 56.1>

  
sor deriving from an alkali metal, such as hydroxides, oxides, carbonates and bicarbonates of any alkali and alkaline earth metal. Examples of suitable catalysts are lithium, sodium, potassium, rubidium, cesium, francium, barium, calcium and magnesium hydroxides, as well as potassium and sodium carbonates and bicarbonates, the oxide calcium etc. The process is described with particular reference to condensation products of phenol and formaldehyde. However, this method is also applicable

  
to condensation products of other phenolic compounds and other aldehydes.

  
The excellent store shelf life and excellent aging characteristics of novel resol compositions, obtained under the influence of alkali metal catalysis, of the present invention are due to the absence of ionic bodies which respond to the removal effected by the aforementioned ion exchange resins, which belong to two types. The first type is a cation exchange resin

  
  <EMI ID = 57.1>

  
an exchange potential with alkali metal cations introduced on the phenol-formaldehyde condensation product as

  
  <EMI ID = 58.1>

  
exchange resin are present in the form of strongly <EMI ID = 59.1>

  
weakly acidic groups (-COOR). Preferably, the cation exchange resin is of the strongly acidic variety. The struc-

  
  <EMI ID = 60.1>

  
cations are fixed is not fundamental to obtaining the new compositions of the present invention. Examples of suitable strong cation exchange residues are sulfonated resins derived from styrene and vinylbenzene, resins.

  
phenol-formaldehyde having sulfonic acid groups, benzene-formaldehyde resins having sulfonic acid groups, etc. Such resins have been sold and put on

  
'The market by several companies under various trademarks.

  
For example, the series of sulfonated copolymers of styrene and. divinyl-benzene, available under the names of "Amberlite 200", "Amberlite 2000", "Amberlite IR-120", "Amberlite IR-122", "Amberlite IR-124" and "Amberlite XE-100" respectively from Rohm & Haas Company is well suited. Other suitable strongly acidic cation exchange resins are sold by The Dow Chemical Company under the designation "Dowex 50-W" and by the Diamond Shamrock Company under the designation "Duolite C-3" and "Duolite C-25". Illustrative examples of weakly acidic cation exchange resins are crosslinked acrylic polymers and copolymers of acrylic acid and divinyl-benzene, available under the respective designations of "Amberlite IRC-84" and "Amberlite.

  
  <EMI ID = 61.1>

  
Some of the cation exchange resins described above are sold as salts, so before using them in accordance with the teachings of the present invention, these resins are treated to convert the ion exchange groups into the free acid form. . This is easily done with the help of a mineral acid like sulfuric acid or hydrochloric acid etc. Usually an excess of the acid is used. The excess acid is then removed with water or with a suitable solvent to remove the salts released. The used resin is regenerated in a similar fashion.

  
The novel resols of the invention are also free of flags capable of being removed by an anion exchange resin in its free base form, that is to say in a form comprising the hydroxyl groups or free amino groups. . the resin can be in strongly basic or weakly basic form. Resins of the strongly basic variety are usually copolymers of styrene and divinyl-benzene, having substitutes.

  
  <EMI ID = 62.1> In the present invention, these strongly basic anionic resins are treated with an alkaline substance, such as aqueous solutions of alkali metal hydroxide, to replace the chloride anions with free hydroxyl and thereby form the radical

  
  <EMI ID = 63.1>

  
resin with water to remove salts of the chloride type. Weakly basic anion exchange resins having polyamine functions linked to a matrix or matrix

  
  <EMI ID = 64.1>

  
and "Amberlite IRA-68". When these various anion exchange resins become used up, they are easily regenerated by treatment with a strong alkaline substance (e.g. 2-5% by weight aqueous solution of potassium hydroxide) to provide the hydroxyl groups again. or, in the case of the weakly basic variety, to eliminate the salts of the amino functions.

  
When using the above-described ion exchange resins in the process of the present invention, the ion exchange operation can be carried out batchwise or continuously. In either procedure, the product of the alkaline condensation of phenol and formaldehyde can be deionized by treating this product with the two different types of ion exchange resins, arranged as a mixed bed.

  
or as single beds. In a mixed bed operation, the alkaline condensation product is brought into close contact with the exchange resin until the pH of the treated liquid substantially stabilizes at a value between about 4 and approx.

  
ron 7 "indicating essentially complete deionization.

  
To perform ion exchange reactions using individual resin beds, the alkaline condensation product is brought into intimate contact with the cation exchange resin in its free acid form for a residence time sufficient to lower the temperature. The pH of the condensation product subjected to this treatment has a value between about 1.5 and about 4. Preferably, the treatment is carried out until the pH stabilizes substantially at a particular value within this range. Usually, the pH stabilizes at a value under

  
  <EMI ID = 65.1>

  
essentially complete removal of cations. The cation exchanged liquid is then intimately contacted with the firm free base of the anion exchange resin for a residence time sufficient to raise the pH to a comparable value. <EMI ID = 66.1>

  
the anion exchange treatment until the pH remains substantially stable at a particular value within this range. Usually the pH stabilizes at a value between about 4.5 and about 6.5. PH stabilization indicates

  
an essentially complete removal of the anions.

  
By "substantial stabilization" of the pH at a particular value within the aforementioned respective ranges is meant a state in which the fluctuation of the pH is not greater than about + 0..3 *

  
In a batch operation, when using a mixture of cation and anion exchange resins or a successive treatment of the alkaline condensation product with these respective ion exchange resins, intimate contact is easily effected by agitation of a suspension of the resins in the liquid condensation product, by any suitable means. When the pH is brought to a value within the aforementioned ranges,

  
the liquid condensation product and the exchange resins are separated by conventional techniques for separating a liquid and the solids such as decantation or filtration. When the deionization is carried out in successive operations, the liquid condensation product is initially treated with the exchange resin.

  
cations and, since the cation-exchanged material is acidic and has not yet been de-anionized, such separation and passage of the liquid to the anion-exchange processing stage must also take place. as quickly as possible to minimize the residence time in the acid solution and thereby prevent polymerization.

  
In continuous operation, the ion exchange resins are conveniently contained in the same columns or in different columns. The flow of the condensation product in the column (s) can be in any direction, although the liquid condensation product is usually passed downwardly through the exchange resins. The rate of flow through the resins is adjusted in order to obtain an effluent from the respective bed of the cation exchange resin and the anion exchange resin, or from the mixed bed comprising these resins, having a pH within the ranges

  
  <EMI ID = 67.1>

  
320 g and approximately 800 g of condensation product per minute per dm <3> exchange resins. However, it should be understood that the flow rate required for any given deionization, in order to obtain the precise pH values, may be higher or lower.

  
and that it is governed by various factors such as the particle size of the ion exchange resin, the size of the ion exchange bed, the viscosity of the liquid condensation product to be treated, the concentration of the catalyst at alkali metal base employed in the condensation reaction and the ability of ion exchange resins. It is easy to determine the values required for

  
flow rate or for recycling by taking samples from the effluent from the respective columns in order to measure it

  
the pH. If the pH responds to the addition of an ion exchange resin
(i.e. if the pH is not substantially stable), the effluent can be recycled to the resin bed or the effluent can be adjusted.

  
  <EMI ID = 68.1>

  
The ion exchange reactions are carried out at temperatures

  
  <EMI ID = 69.1>

  
fit very well. The application of heating from an external source is usually avoided, temperatures above room temperature being achieved simply by introducing a hot product of condensation into the ion exchange system. The pressures do not appear to have a fundamental effect on ion exchange reactions. While atmospheric pressure appears to be most suitable, increased or reduced pressures can also be used as desired. When operating with one or more columns, it may be necessary to have a slightly greater inlet pressure to overcome the pressure drop within any given column, depending on the resistance to the flow and according to the tightness or not of the bed of the exchange resin.

  
The excellent characteristics of the possible duration

  
storage and aging of the resols of the invention are

  
  <EMI ID = 70.1>

  
ionic or ionic which respond to removal by the ion exchange resins described above. The state of deionization and the absence of these ionic bodies exist when the concentration of cations and anions has been reduced to a level low enough that the pH of the resole having undergone the ion exchange remains substantially constant in the presence of the resins. cation exchange and anion exchange repsectives described here.

  
The cations which are removed from the resole during the cation exchange reaction include metal cations corresponding to those of the alkali metal catalyst employed in the condensation reaction. By treating the condensation products until the pH stabilizes substantially in the aforementioned range of between approximately. 1.5 and

  
  <EMI ID = 71.1>

  
made by emission spectroscopy. It should be understood, however, that other metal cations, the nature of which is unknown, can

  
  <EMI ID = 72.1>

  
cations (such as, for example, cationic impurities present in the phenol, in the formaldehyde or in the catalyst or coming from the reactor) and that these other cations could also have an adverse effect on the possible storage time of the resole if these cations are not were not otherwise removed, the nature of the anions that are removed during the

  
  <EMI ID = 73.1>

  
however, such anions can be derived from formic acid or benzoic acid. It should be understood, however, that other theories may also account for the discovery that, unless submitting the resol, having undergone cation exchange,

  
to an anion exchange treatment up to a pH lying in the above-mentioned range of between about 4 and about 7 and

  
  <EMI ID = 74.1>

  
not the maximum stability of the resol against irreversible self-condensation during aging.

  
It is believed that phenol-formaldehyde resols. Deionized of the invention include a complex assortment of bodies of the following types:

  

  <EMI ID = 75.1>
 

  

  <EMI ID = 76.1>
 

  
Regarding the above poly-nuclear structures, it should be understood that corresponding bodies may be present in which the: bridging groups are all methylene groups (-CH2-) as illustrated by (12) or groups

  
  <EMI ID = 77.1>

  
well in which any combination of these groups is present, as illustrated by (13).

  
The distribution and presence of the above bodies vary depending on the nature of the cation of the alkali metal catalyst employed. In the presence of such alkali metal cations, the phenol gives phenate anions whose resonance forms are in the ortho position and in the para position, as shown below:

  

  <EMI ID = 78.1>


  
In the presence of alkali metal catalysts comprising cations having essentially no tendency to form complexes in the ortho position to the hydroxyl, i.e.

  
  <EMI ID = 79.1>

  
more stable, is favored over the forced ortho. Thus, when catalysts such as potassium hydroxide or sodium or francium compounds are used, the formaldehyde will react faster and to a greater degree with the anion in the more stable para position. The product resulting from the condensation will, in turn, have a greater distribution in substance.

  
  <EMI ID = 80.1>

  
above as well as in bodies resulting from condensation of the para-methylol groups as in (8) and (9) with respect to the bodies

  
substituted in ortho like (4) and (6) above although the. bodies of the latter type are usually present. In agreement with this explanation, we find that among the new

  
  <EMI ID = 81.1>

  
tions from condensation products formed in the presence of potassium-based catalysts have a particularly remarkable and superior inherent reactivity to play the role of

  
  <EMI ID = 82.1> industrial scale and which may foam. As described above, commercial or industrial resoles are formed in the presence of barium cations which have a strong tendency to form complexes in the ortho position, which provides resols having a greater distribution of ortho-substituted bodies. -methylol.

   In the presence of salts and in particular of anions which are in such industrial resin, such methylol groups in the ortho position easily undergo self-condensation to give bodies, oligomeric polymers with higher molecular weight and which react less, which which reflects / impulses their poor aptitude for. storage and in the consequent loss of the reactivity of foamable compositions which is observed when, subsequently, these resols are subjected to the addition of relatively strong acid catalysts to rapidly form a polymer foam which one wants to get to. fully heat-cured state o Thanks

  
the use of catalysts such as potassium hydroxides, cesium and francium or their salts, the formation of bodies comprising methylol groups arranged in ortho is reduced and the retention of the initial reactivity of the compositions is thus increased foamable. It should however be understood that whatever the trends relating to the self-polymerization of the resols initially produced, by a reaction catalyzed by-due. an alkali metal, the tendency of any given resole to self-polymerize is suppressed when the resole is presented in a deionized state, as described herein.

  
It should therefore be understood that whatever particular catalyst is employed to form the condensation products which are deionized as described herein, and which

  
regardless of the relative inherent reactivities of the deionized products in their role of foamable compositions, the new resols of the invention have the common characteristic of a possible prolonged storage period due to their deionized state and in particular due to their absence of Anions capable of responding to removal under the effect of treatment with the resins described above for ion exchange.

  
In addition to their deionized state and their possible extended shelf life, the resols of the invention have the additional unusual characteristic of exhibiting a substantially rapid increase in their initial viscosity during hot aging without a corresponding loss in reactivity. inherent allowing them to play the role of foamable compositions. In contrast, the increase in viscosity exhibited by conventional resols during hot aging is associated with a significantly faster rate of irreversible loss of reactivity to act as foamy compositions. The exact mechanism for obtaining the stability of the resols of the invention is not fully explained, and various possible theories can be presented.

   Without wishing to bind thus, one possible explanation is that the absence of the ionic bodies allows a transformation by passing the orthomethylol groups on the position para theimo-dynamically more stable

  
and where intermolecular hydrogen bonding may predominate. Such a balancing can be expressed in simplified form as follows:

  

  <EMI ID = 83.1>


  
where R is a hydrogen atom or a methylol group and, when

  
  <EMI ID = 84.1>

  
alkyl. In contrast, in conventional resols containing ionic bodies, gelation reactions, such as dehydration of ortho-methylol groups to give higher molecular weight polymers, will be favored over the reverse reaction presented above and will be activated by the presence of salts. When preparing deionized resols,

  
  <EMI ID = 85.1>

  
tion of the ortho-methylol groups is suppressed and that lion promotes the intramolecular hydrogen bonding of these groups. In this way, therefore, the absence of the ionic bodies allows the retention of the ortho-methylol groups in a form which allows

  
  <EMI ID = 86.1>

  
devours intermolecular hydrogen bonding.

  
Phenol-formaldehyde condensation products, which are deionized according to the teachings of the present invention, include those prepared at molar ratios of formal-

  
  <EMI ID = 87.1>

  
Usually, formaldehyde is added to the reaction system as an aqueous solution containing from about 3.5 to about
45% by weight of HCHO. The relative proportions of phenol and formaldehyde are often also expressed in terms of the formaldehyde factor, which defines the number of parts by weight of the aqueous formaldehyde solution that is introduced into the zone.

  
  <EMI ID = 88.1>

  
The level of formaldehyde will vary depending on the content of formaldehyde contained in the particular aqueous solution employed o When expressed on the basis of a 37% by weight aqueous solution of formaldehyde, the factor is usually between about 100

  
and around 190 and more usually between around 110

  
  <EMI ID = 89.1>

  
The concentration of the alkali metal catalyst employed to carry out the condensation reaction can vary over a relatively wide range, for example between 0.1 and about
10 parts by weight (and usually this concentration is not more than about 5 parts by weight) per 100 parts by weight of the phenol introduced into the reaction zone.

  
The condensation reaction is carried out at temperatures between about 60 [deg.] And about 110 [deg.] C and more usual.

  
  <EMI ID = 90.1>

  
condensation at atmospheric pressure, although a reduced pressure is usually used, corresponding for example to a value between about 150 and about 650 mm of mercury. The pressure is adjusted to match the temperature desired for the reaction. The duration of condensation can vary between about half an hour and about 15 hours.

  
A generally preferred overall set of conditions

  
of the condensation includes temperatures between approx.

  
  <EMI ID = 91.1>

  
about one and about four and a half hours, and concentrations

  
of the catalyst between about 0.2 and about 4% by weight
(relative to phenol).

  
The particular set of condensation reaction conditions employed will depend to a large extent on the end application envisioned for the deionized resole produced, such as the desired quality of density of the phenolic foam that is desired.

  
  <EMI ID = 92.1>

  
is all the more reactive and, thus, the density of the phenolic foam produced from this resole is all the lower than the severity or. the hardness of the combination of reaction conditions decreases. For example, when the condensation is carried out at a formaldehyde factor of between approximately
160 and about 180 (based on a 37% by weight solution

  
  <EMI ID = 93.1>

  
generally obtains resols which, when subsequently deionized, can foam to give a higher mass foam. volume than the resols obtained when the condensation is carried out under these conditions but at a lower formaldehyde factor, between about 110 and about 120. By way of further illustration, a result similar to a formaldehyde factor can be obtained from about 160 to about 180 by lowering the severity of one or more of the other reaction conditions, i.e., temperature, reaction time or catalyst concentration such as, in particular, lowering the concentration catalyst to bring it back

  
to a value of between about 0.5 and 1% by weight. Condensation conditions also appear to influence the amount of free phenol contained in the resole product which, as with conventional resols provided as foamable compositions, can vary over a relatively wide range, for example between about 2 and about 40 in weight. In general, the content of free phenol (within this range) is greater the less severe the combination of condensation conditions.

  
It will be understood that the above indications are general rules concerning the various reaction conditions which, for any given catalyst derived from an alkali metal, promote the formation of condensation products which, when subsequently deionized. # 65533; As described herein, give stable resols having variable reactivity when made to act as foamable compositions. From the standpoint of obtaining resols having a particularly remarkable combination of improved inherent stability and improved inherent reactivity to act as foamable compositions, the preferred catalysts are compounds of potassium, cesium and francium.

  
Among them, potassium compounds constitute the preferred class of catalysts due to their greater availability. We

  
  <EMI ID = 94.1>

  
found on a commercial or industrial scale. These various grades include potassium hydroxide produced by electrolysis of potassium chloride in normal diaphragm electrolytic cells and in diaphragm cathode cells.

  
  <EMI ID = 95.1>

  
Potassium chloride is electrolyzed in an electrolysis device comprising a mercury cathode forming chlorine at the anode and metallic potassium at the mercury cathode. The various amalgams formed between potassium and mercury, as well as the mercury itself, are then passed through a decomposition device containing graph or iron where. the amalgam is treated with water vapor or with water forming a solution of potassium hydroxide and hydrogen.

   potassium hydroxide produced by the electrochemical process of the mercury cathode cell has a residual potassium chloride content which, in general, is lower than that of potassium hydroxide recovered from normal electrolysis of chloride potassium in a chlorine-supplying cell in which the anode compartment and the cathode compartment are simply separated by a diaphragm. Potassium hydroxide, from

  
a diaphragm cell or a mercury cathode cell, which has been subjected to further purification to decrease the content of potassium chloride and / or other impurities, such as trace metals, is also suitable as cataly-

  
  <EMI ID = 96.1>

  
Potassium is also available in various physical forms and suitably employs any of these forms in the practice of the present invention, such as lozenges, flakes, nutshell briquettes, etc. .

  
It has been found that the deionized resols of the present invention, derived from condensation products which have been produced in the presence of potassium hydroxide obtained in the grade from the mercury cathode cell, have the unexpected additional property of being able to provide reproducibly a phenolic foam having significantly reduced friability. the exact reason for this improvement in friability resistance, and the mechanism. allowing the achievement, have not been elucidated. An example illustrating hydroxy-

  
  <EMI ID = 97.1>

  
of mercury, for use as a condensation catalyst in accordance with this particular aspect of the present invention, is the hydroxide available from Hooker Chemical Corporation and Diamond Shamrock Chemical Company.

  
  <EMI ID = 98.1>

  
about 10 and about 60% by weight and is usually not more than about 40 to 50% by weight. Water, is introduced

  
in the system in the form of the formaldehyde solution and it is also introduced with the catalyst which is added preferably in the form of a preformed aqueous solution. Variable amounts of water are also formed as a by-product during the condensation reaction. The water present in the reaction system can be left in the condensation product and passed as it is to the ion exchange reactions described above, or else the condensation product can be subjected to it. conventional techniques, such as stripping or evaporation, to separate the aqueous distillate and reduce the water content thereof to.

  
  <EMI ID = 99.1>

  
of a substantially non-aqueous state. However, when carrying out the ion exchange reactions employing individual beds of the respective exchange resins, the condensation product should contain a sufficient amount of diluent before it passes to the cation exchange reaction in order to to minimize polymerization of the resulting acidic material prior to anion removal. For this purpose, the condensation product

  
  <EMI ID = 100.1>

  
approximately, by weight of diluent. The diluent can be infused water.

  
  <EMI ID = 101.1>

  
as a normally added liquid in which the resole is soluble, or a combination of water and an added organic diluent. Suitable organic diluents include one or more of the following compounds: alcohols such as, for example, isopropanol; ketones like acetone and methyl-ethyl-

  
  <EMI ID = 102.1>

  
esters such as methyl acetate; acetals such as dimethoxymethane and acetaldehyde dimethyl acetal; hemi-acetals; and other such oxygen-containing polar liquids in which the resole is also soluble.

  
Other suitable diluents include normally liquid halogenated aliphatic compounds in which the resole is.

  
soluble. As examples of diluents belonging to the latter class, mention may be made of methylene chloride, chloroform,

  
  <EMI ID = 103.1>

  
aforementioned oxygenated diluents, such as hexachloroacetone.

  
The concentration of a liquid condensation product is easily carried out to a water content. particular by evaporation at a reduced pressure such as, for example, a pressure corresponding to approximately 1 to approximately 200 mm of mercury,

  
  <EMI ID = 104.1>

  
carry out in several stages the separation of the aqueous distillate from the condensation product, for example by carrying out a partial evaporation before the treatment with the exchange resin of

  
cations and then performing an evaporation after the treatment with the anion exchange resin, or in a single step, for example after the anion exchange reaction.

  
It should therefore be understood that although the alkaline condensation product is aqueous, the deionized resols of the invention can be provided as aqueous or non-aqueous compositions comprising non-aqueous compositions which are in concentrated form or in dissolved form in. one of the aforementioned organic solvents.

   A method which is particularly suitable for providing the deionized resoles of the invention in anhydrous or substantially anhydrous form (0.5% by weight of water or less) consists in removing the aqueous distillate from the alkaline condensation product, to be added to the mixture. condensation product thus treated or stripped, an amount of isopropanol such that the combined weight of any remaining water and isopropanol is at least equal to about 10% by weight, to subject the resulting mixture to the exchange reactions ions and, as desired, partially or completely removing isopropanol from the deionized resole. during

  
  <EMI ID = 105.1>

  
propanol, which gives the non-aqueous products of the invention.

  
When the deionized resols of the invention are to be used in the manufacture of a phenolic foam, the water content of these resols, as well as the content of any organic diluent added, is reduced to a final level not greater than approx.

  
  <EMI ID = 106.1>

  
Usually, the concentration of water is reduced to between about 4 and about 0.5% by weight, or less. It is desirable to minimize the water content of resols intended for foaming in order to minimize shrinkage of the foam produced. The initial viscosity of the deionized resols of the invention, which have such relatively low water contents, as well as the viscosity of the non-aqueous products, ranges over a relatively wide range, for example between about 400 and about 150,000 cPo (Brookfield at 25 [deg.] C),

  
although the initial viscosities are usually not more than about 100,000 cPo.

  
The deionized compositions and the process of the present invention have been described with particular reference to the reaction of the actual phenol and formaldehyde. It should be understood, however, that the teachings of the present invention are also applicable to compositions of resols from other phenolic compounds and other aldehydes. For example, in addition to the phenol itself, other compounds having a phenolic hydroxyl group (i.e. -OH attached directly to a benzene ring) and having 2 or 3 unsubstituted ring carbon atoms, in ortho and para position with respect to phenolic hydroxide, are well suited.

   Such compounds include mononuclear phenolic compounds as well as polynuclear phenolic compounds, i.e. compounds having more than one benzene ring to which a phenolic hydroxyl group is attached. For example, suitable mono-nuclear phenols are those compounds having the general formula:

  

  <EMI ID = 107.1>


  
  <EMI ID = 108.1>

  
When present, the alkyl groups can have one to 20 carbon atoms. Here are examples illustrating suitable compounds corresponding to the above formula: phenol,

  
resorcinol, catechol, ortho-cresol, meta-cresol,

  
  <EMI ID = 109.1>

  
  <EMI ID = 110.1>

  
decylphenol, p-octadecylphenol, etc.

  
Here are examples illustrating phenolic compounds

  
  <EMI ID = 111.1>

  
following tri-nuclear and tetra-nuclear compounds, which are the respective products of the reaction of phenol and acrolei-

  
  <EMI ID = 112.1>

  
(molar ratio 4: 1):

  

  <EMI ID = 113.1>


  
(where the bridging alkylidene groups are attached to the respective benzene rings at the para carbon atoms to the phenolic hydroxyl) illustrate other suitable polynuclear phenolic compounds.

  
It should be understood that any of the above phenolic compounds can be used individually or in combination. Usually, however, para-substituted alkylphenols and / or poly-nuclear phenolics are used with the phenol. It is also contemplated, as suitable for serving

  
  <EMI ID = 114.1>

  
para- (2-phenylethyl) -phenol, ortho, para- (2-phenylethyl) -phenol and the like. When the phenols are used in combination with other phenolic compounds such as, for example, the aforementioned para-alkylphenols, the aforementioned beta-phenylethylphenols and the aforementioned poly-nuclear phenols, the additional phenolic compound is usually used in an amount not exceeding not about 50 parts by weight per 100 parts by weight of the phenol.

  
In addition to formaldehyde, the following are other aldehydes useful for forming the condensation products from which the deionized phenolic resols of the invention can be derived: glyoxal, acetaldehyde, chloral, furfural and benzaldehyde. In addition,

  
  <EMI ID = 115.1>

  
which is usually added in aqueous solution as previously described, or in the form of its polymers to. low molecular weight such as para-formaldehyde or in the form of other sub-

  
  <EMI ID = 116.1>

  
tions, described herein, of the condensation reaction. It should be understood that one can use, individually or in combination

  
  <EMI ID = 117.1>

  
dehyde.

  
The compositions of the deionized, normally liquid and stable phenolic resols of the present invention are used particularly advantageously to form cellular phenolic products in plaque form (free rise), in molded form or in spray-applied form. sprays, by conventional molding techniques. The density or density of cell products varies over an inter-

  
  <EMI ID = 118.1>

  
and about 480 g per dm '. The density of the produced foam obtained from any given foam production formulation is determined primarily by the reactivity of the resole which, as previously defined herein, is the rate at which the foam.

  
  <EMI ID = 119.1>

  
acid catalysts. In general, for any given formulation, the density of the foam produced from a given resol is all the lower the more reactive this resol is and, likewise * the density is all the higher the higher the resol is less responsive.

   Thus, there is generally an inverse relationship between density (as well as the duration of the polymerization reaction, such as the time until cream formation and the rise time), on the one hand, and the reactivity of resols, on the other hand It should be understood that one can mix a very highly reactive deionized resole of the invention which is suitable to form a foam having a density of less than about 8 g / dm <3> such as resols prepared using a relatively mild combination of reaction conditions, with less strongly reactive deionized products,

   to obtain a particular reactivity suitable for producing a foam having a desired specification for its density o Since the deionized resols of the invention have an extended shelf life possible due to their greater inherent stability to self. polymerization, mixtures based on deionized resols having different reactivities also have

  
a good possible shopping time.

  
For most end applications of the phenolic foams produced from the liquid deionized resols of the present invention, the other constituents of the formulations

  
or compositions for obtaining a foam usually comprise an acid catalyst, a swelling or foaming agent and a surfactant or surfactant.

  
The catalyst forming part of the foam formulation can be a mineral acid or an organic acid and is usually a relatively strong acid. Examples of suitable acid catalysts for the formation of polymeric foams are: hydrochloric acid, sulfuric acid, acidic acid,

  
from flucboric, formic acid; mixtures of acid catalysts, based on boric acid or its anhydride) with organic hydroxyl acids having a hydroxyl group on a carbon atom which is not more than one carbon atom distant from the carboxyl group such as, in particular, oxalic acid, as described in US Pat. No. 3,298,973, and other acid catalysts known in the art of phenolic foaming. Other suitable catalysts are organic sulfonic acids such as any of the following acids which can be used individually or in combination with each other: a single benzene -suif acid, an acid

  
  <EMI ID = 120.1>

  
as, etc., as well as resin-sulfonic acids such as the products of the phenol / sulfuric acid / formaldehyde reaction, described

  
  <EMI ID = 121.1>

  
Suitable mixtures of organic sulfonic acids for use as catalyst components for phenolic foam production formulations containing the resols of the present invention are modified toluenesulfonic acids, such as those available from Witco Chemical Company, Inc. under the trademark "Ultra TX Acid" and "Sulframin TX Acid".

  
Importantly, the concentration of the catalyst contained in the foaming reaction mixture can vary between about 0.5 and about 40 parts by weight, per 100 parts by weight of the resole. deionized, and usually no more than about

  
20 parts of the catalyst. The preferred concentration varies depending on the nature of the catalyst. For example, fluoboric acid is a particularly active catalyst for the formation of phenolic foam and is thus normally used in an amount of not more than about 10 parts per 100 parts of resole.

  
It is noted that some of the aforementioned acid catalysts are

  
  <EMI ID = 122.1>

  
However, when used in combination with conventional resols supplied in foamable resins, the salts contained in these resols remain in the foam produced and contribute to the corrosive nature of the foam. phenolic foam produced. On the contrary, another characteristic and another advantage of the resols of the present invention is that they are inherently less corrosive than commercial resins, due to the deionized state of the resols of the invention. Thus, their use in combination with the non-corrosive type of acid catalyst provides a phenolic foam with lower corrosivity.

  
As the source of the swelling action, any of the deionized resols of the invention can be employed.

  
  <EMI ID = 123.1>

  
For example, one class of suitable consternent agents is polyhalogenated saturated fluorocarbons having a boiling point between about -40 [deg.] C and about +93 [deg.] C, such as

  
  <EMI ID = 124.1>

  
hydrocarbons such as methylene chloride and 1,2-dichlor- - - ethane. Another class of suitable bulking agents is

  
  <EMI ID = 125.1>

  
amount between about 2 and about 30 parts by weight per 100 parts by weight of resole contained in the formulation

  
  <EMI ID = 126.1>

  
about 4 and about 16 parts by weight.

  
A class of active surfacing constituents suitable for

  
formulations for producing a phenolic foam is formed by organic surfactants. Non-ionic organic surfactants

  
  <EMI ID = 127.1>

  
(canine eg ethylene oxide, propylene oxide or combinations thereof) and alkylphenols such as nonylphenol, dodecylphenol etc., are particularly useful surfactants. this end. Other suitable organic surfactants are known in the art of foaming phenolic resins and include, for example, the surfactants described in the aforementioned US Patent No. 3,389,094.

  
Another class of surfactants is constituted by

  
  <EMI ID = 128.1> <EMI ID = 129.1>

  
In general, the surfactant active agent is present in formulations for producing a foam in an amount of from about 0.5 to about 10 parts by weight, per 100 parts by weight of the solved constituent.

  
It is also possible to carry out the foaming of the resols of

  
the present invention in the presence of other additives such as fillers, pigments and compounds intended to render the foam produced non-combustible to red. Compounds containing phosphorus are particularly suitable for the latter purpose,

  
  <EMI ID = 130.1>

  
phosphonium.

  
In addition to their application to the formation of cellular phenolic resins, the deionized phenolic resols of the invention are also useful for a multitude of other purposes such as, for example, in the manufacture of adhesives, coatings, films, etc. 'thermosetting molded articles, etc.

  
The following non-limiting examples are presented in order to illustrate the present invention.

  
In the examples, and for the sake of brevity, the ion exchange resins used are designated as cation exchange resins A and B and anion exchange resin A. These respective resins are identified below:

  
The cation exchange resin A is the free acid (H +) form of "Amberlite IR-120" from Rohm and Haas Company.

  
Cation exchange resin B is "Amberlite IR-200" resin from Rohm and Haas Company which, before being used in the examples, was converted to its free acid form by the following procedure: About 1300 ml are subjected to "IR-200" resin, contained in a column 17.5 cm in diameter

  
  <EMI ID = 131.1>

  
of 3.8 liters of 4.0% by weight hydrochloric acid, then allowed to stand for 10 to 15 minutes while the resin bed settles, and then downdraft was swept with distilled water (approximately 11 to 15 liters) until

  
that the effluent is neutral to the paper at pH.

  
Anion exchange resin A is "Amberlite IRA-900", also sold by Rohm and Haas Company. It is provided in chloride form and therefore, before being used in the examples, it,

  
  <EMI ID = 132.1>

  
  <EMI ID = 133.1>

  
Tres of a 3% aqueous solution of potassium hydroxide in a 4 liter beaker for 30 minutes. The pH of the suspension is measured to establish alkalinity. The resin is then filtered off with suction and washed in small portions with distilled water (about 19 liters) until a constant neutral pH is obtained.

  
The spent ion exchange resins are converted into their respective free acid and hydroxylated forms by following the above procedures except that prior to regeneration these resins are first washed by a downdraft of about 3 to 4 times their volume of isopropanol in order to remove the organic resin (i.e. the resol) which tends to coat the beads with ion exchange resin.

  
Potassium hydroxide serving as a catalyst for the formation of condensation products from which one

  
obtained the deionized resols A to H, J to Z and XX of the invention is that sold by JT Baker and Company under the name "Potassium Hydroxide Pellets," Baker Analyzed "Reagent" (potassium hydroxide pellets; reagent " analyzed by Baker ";

  
  <EMI ID = 134.1>

  
"mercury cathode cell", and this hydroxide is described in more detail with particular reference to the preparation of these particular resols.

  
The values given in the examples for the viscosity, the pH, the water content and the methylol content of the resols, and the density of the foams produced from the resols were determined as follows:

  
The viscosity, indicated in centipoise (cPo) was

  
  <EMI ID = 135.1>

  
measurements by placing the resole sample in a bath at constant temperature (25 [deg.] C unless otherwise specified) for '
16 hours, choosing a spindle to give a mid-range reading at 6-30 rpm. Readings are taken after 3, 4 and 5 minutes; the viscosity shown in the examples is the average of these three readings.

  
the density of the foam is indicated in g / dm <3>,

  
  <EMI ID = 136.1>

  
Model 96.

  
The water content of the resols was determined by the Karl Fischer method, modified by the use of a solution, in "methyl-cellosolve", of sulfur dioxide and

  
  <EMI ID = 137.1> particular iodine (about 0.2) which indicates the number of grams

  
  <EMI ID = 138.1>

  
50 ml of anhydrous methanol and 75 ml of redistilled pyridine are used. The titration reagent is added to the dissolving medium until the indicator on the meter remains at 150 milli-amps which is considered the end point.

  
The sample (0.5-1.0 g) to be analyzed is then added and titrated with the reagent until the indicator is maintained.

  
  <EMI ID = 139.1>

  
the water content of the sample continues as follows:

  

  <EMI ID = 140.1>


  
where A is the number of milliliters of the. titration reagent required for sample to reach end point.

  
  <EMI ID = 141.1>

  
N [deg.] 6, pages 883-884 (June 1951).

  
Examples 1-3

  
  <EMI ID = 142.1>

  
According to these examples, three resols are prepared at a formaldehyde factor of 170, using potassium hydroxide as a catalyst and carrying out 3.25 hours at

  
  <EMI ID = 143.1>

  
then carrying out a partial dehydration of the condensation product, successively treating with the cation exchange and anion exchange resins and finally carrying out a "stripping" removal to remove the additional water. Except where noted, the composition of the respective reaction mixtures and the procedure employed are substantially the same as illustrated by the following description of the preparation of Resol A:

  
In a reactor equipped with a "Trubor" stirrer, a thermometer, a nitrogen inlet and a water-cooled distillation head, are introduced (1) 1600 g, or 17 moles , of molten phenol, prepared by heating for about 18 hours a solid phenol in an air oven at 55 [deg.] C, (2) 2740 g

  
  <EMI ID = 144.1>

  
maline ") corresponding to 1022 g (34 mol) of formaldehyde,

  
and a solution containing 32.3 g of potassium hydroxide (pure-

  
  <EMI ID = 145.1>

  
Potassium xide which is added while stirring as a catalyst raises the pH of the phenol / formaldehyde solution from 3.3 to 8.7. After reducing the pressure on the system to a value corresponding to 285 mm of Hg, we heat

  
  <EMI ID = 146.1>

  
The heating is then stopped and the heat given off by the mixture is left to allow it to reach its maximum temperature of 75 [deg.] C at which vigorous reflux begins. The heat released maintains reflux at 75 [deg.] C (pressure corresponding to

  
  <EMI ID = 147.1>

  
corresponding to 295-310 mm Hg) for a total condensation period (including the initial 40 minutes of reflux) of 3.25 hours. The pressure is then slowly reduced to

  
  <EMI ID = 148.1>

  
nutes, while collecting an aqueous distillate. The removal of the aqueous distillate is continued for about 1 hour and then

  
  <EMI ID = 149.1>

  
and it has a pH of 8.5. It is then combined with 1000 g of cation exchange resin A. The resulting mixture was stirred until the pH stabilized at a value of 2.2, which took about 10 minutes. The cation exchange resin was filtered off through a fine mesh cloth ("Silkalene"). The filtrate is then combined, without undue delay, with 300 g of the anion exchange resin A until the pH reaches 4.6.

  
  <EMI ID = 150.1> <EMI ID = 151.1>

  
volatiles and in particular water, the filtrate is heated until a temperature of 65 [deg.] C is obtained at a pressure corresponding to 40 mm, which takes approximately 6 hours. After this evaporation operation under reduced pressure (stripping), the liquid product is heated for approximately 1 hour at 65 [deg.] C under

  
  <EMI ID = 152.1>

  
In the second step of increasing the consistency, a light yellow liquid product weighing 1900 g is obtained, which corresponds to a yield of 117 g per 100 g of phenol. This product, which is referred to herein as "resol A", has a Brookfield viscosity.

  
  <EMI ID = 153.1>

  
a hydroxyl number of 252 mg KOH / g.

  
In Example 2, Resol B is prepared on a scale double that of Resol A. After addition of potassium hydroxide (catalyst), the pH of the reaction mixture is

  
  <EMI ID = 154.1>

  
water until about 64 g of aqueous distillate per 100 g of phenol has been collected. The partially dehydrated reaction mixture (water content of about 25% by weight) has a pH of 8.5 and combines it with 2000 g of cation exchange resin B. The resulting suspension is stirred until

  
  <EMI ID = 155.1>

  
Lifting the cationic resin, the filtrate is combined with 750 g of anion exchange resin A until the pH of the suspension is equal to 4.50. After separation of the resin, the

  
  <EMI ID = 156.1>

  
liquid product to cool to room temperature without further heating it under these conditions. The liquid product is obtained with a yield of 11.9 g per 100 g of phenol. This product, which is referred to herein as "resole B", has a viscosity of 12,800 cPo at 25 [deg.] C, a free water content of

  
  <EMI ID = 157.1> weight and hydroxyl number of 341 mg KOH / g.

  
In Example 3, "resol C" is prepared on the same scale as resol A, except that 600 g of anion exchange resin A are used. After addition of potassium hydroxide (catalyst), the pH of the reaction mixture is also 8.7. The stage of partial water removal after condensation is carried out until approximately 70.9 g of distillate per 100 g of phenol has been collected. The partially dehydrated reaction mixture, which has a pH of 8.55, is combined with 1000 g of cation exchange resin A and the resulting suspension is stirred until the pH stabilizes at 2.35. , which takes about 5 minutes. After the filtration stage, the filtrate is combined with 600 g of the anion exchange resin A until the pH of the suspension is brought to 5.45, instead of 4.6 as in 1. example 1.

   After separation of the anion exchange resin, the filtrate has a pH of 5.40.

  
The final stage of dehydration is carried out by subjecting the reaction product to stripping for a total of 3.5 hours at 65 [deg.] C under reduced pressure (corresponding to 40 mm Hg) and

  
then let cool down to room temperature

  
without further heating under these conditions. The liquid product is obtained with a yield of 119.1 g per 100 g of phenol. This

  
  <EMI ID = 158.1>

  
viscosity of 6710 centipoise at 25 [deg.] C.

  
Examples 4 &#65533; 6

  
According to part (A) of these examples, the hot aging of resols A, B and C is carried out for various periods of time and, as described in part (B), foams are prepared from these resols before and after hot aging.

  
(A) Hot aging procedure

  
The hot aging of the resols A is carried out,

  
  <EMI ID = 159.1>

  
employing substantially the same procedure as that typically represented by the following description of aging

  
hot from resol A:

  
About 1400 g of resol A are placed in a 5-liter, 4-necked flask fitted with a stirrer, thermometer, nitrogen inlet tube and condenser.

  
  <EMI ID = 160.1>

  
(examples 4-1). After this initial aging period, a portion (approximately 450 g) of the resole, which is designated A-1, is removed from the flask for the foaming and the determination of the viscosity. The remainder of the resole in the flask is subjected to a second stage of heating (Examples 4-2) and further hot aging is carried out for an additional period.

  
  <EMI ID = 161.1>

  
foaming and 'for viscosity measurements a portion of the resole, referred to as A-2, which has now undergone heat aging for a total of 10.5 hours. We submit the

  
  <EMI ID = 162.1>

  
during an additional period of 5 hours (examples 4-3). The remaining resol, which is now designated A-3, has thus undergone aging for a total period of 15.5 hours and is subjected, also to tests to determine its behavior during foaming and to a measurement of its. viscosity.

  
Resols B and C were also subjected to three stages of heat aging for various periods of time. After each stage, we submit the respective resols, designated

  
  <EMI ID = 163.1>

  
ment, during foaming and viscosity determinations.

  
(B) Reaction and procedure for foaming The foam formulation, used to prepare <EMI ID = 164.1>

  
  <EMI ID = 165.1>

  

  <EMI ID = 166.1>
 

  
Notes:

  
  <EMI ID = 167.1>

  
The foams are prepared according to the following general procedure. The resole, the active silicone surfacing and the swelling agent contained in a cardboard cup of 1 liter capacity are first of all thoroughly mixed, by stirring during
Approximately 60 seconds at approximately 1700 rpm using an air motor fitted with a stainless steel shaft comprising three stainless steel blades; the temperature of this mixture is between 27 [deg.] and 30 [deg.] C. We then pour the weighed quantity

  
  <EMI ID = 168.1>

  
vigorously for 20 seconds. The resulting mixture is poured into a cardboard boot (20cm x 20cm x 15cm); we note the time (in seconds) for the formation of a cream and for the rising, and we measure the height (in cm). We consider that the

  
  <EMI ID = 169.1>

  
diluting the catalyst until the mixture visibly begins to expand. The time to rise is measured from the time of addition of the catalyst until the expansion ceases. We measure the height of the lift corresponding to the time indicated for the lift. The foams are allowed to stand at ambient conditions for at least 3 days before cutting them and performing the tests.

  
  <EMI ID = 170.1>

  
The duration of aging, as well as the viscosity, the time until a cream is obtained, the rising time and the density of the foam before and after aging.

  
  <EMI ID = 171.1>

  
For comparison purposes, Table II also indicates data concerning test C-1 based on a phenol-formaldehyde resole for foaming, produced industrially and having a quality intended to have the following specifications:

  
  <EMI ID = 172.1>

  
Typical condensates for making this grade of resole for foaming include a formaldehyde factor of 170 (based on a 37% aqueous formaldehyde solution); a condensing temperature of about 75 [deg.] C; a

  
  <EMI ID = 173.1>

  
Barium hydroxide octabydrate as a catalyst (3.6 parts by weight per 100 parts by weight of the phenol). The alkaline condensate is partially dehydrated (approximately 70 g of distillate for
100 g of phenol), and neutralized with a dilute solution

  
  <EMI ID = 174.1>

  
resulting is probably in a solvated form and, in any case, it remains in the resole as one of the constituents of it. <EMI ID = 175.1>

  
  <EMI ID = 176.1>

  
ordinary ambient conditions, and therefore it is shipped normally and stored under refrigeration (5 [deg.] C) in order to minimize self-condensation giving higher molecular weight constituents and the accompanying loss of reactivity. the foamable composition. The particular burden of this resol. industrially produced, which is used in the comparison test.

  
  <EMI ID = 177.1>

  
that it is made, it has a viscosity of 4650 cPo, a water content of 5.6% by weight, a pH of 5.9 and a specification of

  
  <EMI ID = 178.1>

  
management.

  
As for the deionized resols A, B and C of the in-

  
  <EMI ID = 179.1>

  
by following the aging procedure above. After each of these aging periods, the resol

  
  <EMI ID = 180.1> viscosity of resol I, before and after each stage of aging, as well as the reactivity of this resol. The respective foams were prepared by following the general foaming procedure described above, and by using formulation A to obtain a foam of Table I. These results are also shown in Table II which follows.

  

  <EMI ID = 181.1>


  

  <EMI ID = 182.1>


  

  <EMI ID = 183.1>
 

  
The data in Table II are all based on Foam Production Formulation A. These data concern

  
  <EMI ID = 184.1>

  
The invention have excellent reactivity as foamable materials, both initially and after accelerated aging.

  
  <EMI ID = 185.1>

  
weaker (test C-1) and poor aging characteristics, as reflected, in particular, by a vo-

  
  <EMI ID = 186.1>

  
hot aging.

  
Examples 7 and 8

  
Preparation of resols D and E

  
In these examples, two resols are prepared with a formaldehyde factor of 170, using the same quantities of phenol, formaldehyde and an aqueous solution of hydroxide: potassium as a catalyst as those used to prepare resole A of Example 1. After addition of the catalyst, the pH of

  
reaction mixture is 8.7. The condensation is carried out substantially as described in Example 1, except that the total duration of the condensation at 75 [deg.] C is 4.25 hours instead of 3.25 hours. A partial removal of water is carried out under reduced pressure (corresponding to approximately 80 mm of Hg) until, respectively, 70.2 g (example 7) and 69.2 g (example 8) of distillate per 100 g of phenol. The respective values of

  
  <EMI ID = 187.1>

  
When preparing Resol D of Example 7,

  
the partially dehydrated mixture is combined with 1000 g of

  
cation exchange resin A, and the resulting suspension was stirred until the pH stabilized at a value of 2.3, which took about 15 minutes. The cation exchange resin is separated by filtration and the filtrate is then combined with 1000 g of the anion exchange resin A, until

  
so that the pH of the suspension reaches 4.85, which takes about 17 minutes. After filtration, the filtrate obtained has a pH of 4.9 and is heated to 65 [deg.] C under reduced pressure (corresponding to 40 mm Hg) for about 5.0 hours to effect the removal of the particles. volatile matter and in particular water. After this evaporation operation, the liquid product is heated for about half an hour at 65 [deg.] C under reduced pressure.

  
  <EMI ID = 188.1>

  
in a yield of 117.1 g per 100 g of phenol. This product, referred to herein as resole D, has a Brookfield viscosity of 16,500 cPo at 25 [deg.] C.

  
For the preparation of Resol E of Example 8, the partially dehydrated mixture is combined with 1000 g of cation exchange resin A, and the resulting suspension is stirred until the pH stabilizes at a value of 2.4, which takes about 15 minutes. The cation exchange resin * was filtered off and the filtrate was then combined with 800 g of the anion exchange resin A until

  
  <EMI ID = 189.1>

  
filtration to remove the anionic resin, the filtrate obtained has a pH of 5.40. Or. Heats the filtrate to 65 [deg.] C under

  
a reduced pressure corresponding to 40 mm of Hg for approximately 3 and a half hours to remove volatile matter and in particular water. After this stripping operation by evaporation, the liquid product is obtained with a yield

  
  <EMI ID = 190.1>

  
Example

  
Preparation of Resol F

  
According to the present example, an additional resol is prepared.

  
  <EMI ID = 191.1>

  
same amounts of phenol, formaldehyde and aqueous potassium hydroxide solution (catalyst) as those used to prepare resole A of Example 1. After addition of the catalyst, the pH of the reaction mixture is 8.65. The condensation is carried out substantially as described in Example 1, except that the total duration of the condensation at 75 [deg.] C is 2.25 hours instead of 3.25 hours. Partial removal of the water is carried out under reduced pressure (corresponding to approximately 80 mm Hg) until approximately 62.9 g of distillate per 100 g of phenol has been collected.

  
After cooling to 45 [deg.] C, the pH of the partially dehydrated mixture is 8.65. It is then combined with 850 g of cation exchange resin B. The resulting suspension is stirred

  
  <EMI ID = 192.1>

  
takes about 30 minutes, after which 450 g of the cation exchange resin A is added to obtain a pH of 2.7, which takes about 15 minutes. After removal by filtration of the cation exchange resins, it is combined. filtrate with
40C g of cation exchange resin A until the pH reaches 5.30, which takes about 26 minutes. After his filter-

  
  <EMI ID = 193.1>

  
under a reduced pressure corresponding to 40 mm of Hg for approximately 5.5 hours to remove volatile materials and in particular water. After this evaporation operation, the liquid product is heated for 2 and a quarter hours

  
  <EMI ID = 194.1>

  
The liquid product is obtained in a yield of 118 g per 100 g.

  
of phenol. This product, referred to herein as resol F, has a viscosity of 6500 cPo at 250C.

Example 10

  
Preparation of resol G-

  
According to the present example, a resole with a formaldehyde factor of 170 is prepared using the same amounts of phenol, formaldehyde and the aqueous solution of potassium lyiroxide (catalyst) as those used to prepare resole A of Example 1. After addition of the catalyst, the pH of the reaction mixture is 8.7. The condensation is carried out substantially as described in Example 1; except that the total duration

  
condensation at 75 [deg.] C is 5.25 hours instead of 3.25 hours. A partial removal of water is carried out under a pressure

  
  <EMI ID = 195.1>

  
collected about 62.8 g of distillate per 100 g of phenol. After cooling to room temperature, the pH of the partially dehydrated condensate is 8.6. This condensate is then combined with 1000 g of cation exchange resin A and the suspension is stirred. -resulting until the pH stabilizes at a value of 2.3, which takes about 13 minutes. We separate by

  
  <EMI ID = 196.1>

  
Following the filtrate with 600 g of the anion exchange resin A, until the pH reaches 5.40, which takes about 15 minutes. After filtration intended to separate the anionic resin, the filtrate also has a pH of 5.40. We heat this

  
  <EMI ID = 197.1>

  
40 mm of Hg for approximately 5 and a quarter hours to remove volatile matter and in particular water, after which the product is allowed to cool to room temperature. The liquid product is obtained in a yield of 121.5 g per 100 g of phenol. This product, referred to herein as being

  
  <EMI ID = 198.1>

  
Examples 1,1-14

  
According to these examples, we subject the resols D to G, res-

  
  <EMI ID = 199.1>

  
atmospheric pressure under nitrogen, by applying the procedure described above in "A" 'of Examples 4 to 6. The foaming characteristics of the resols, before and after hot aging, are determined using formulation A from production.

  
  <EMI ID = 200.1>

  
tie (B) of Examples 4 to 6. Table III below gives the results of this study on aging and on the characteristics of foam formation.

  

  <EMI ID = 201.1>


  

  <EMI ID = 202.1>


  

  <EMI ID = 203.1>
 

  
The data in Table III show above all that the resols of the invention, having undergone an ion exchange and which originate from condensation products whose condensation lasted less and longer, than the 3.25 hours used to form resols A, B and C also have good aging properties and good reactivity for the formation of a foam. These data also show that at a formaldehyde factor of 170, when the hardness of the condensation conditions is reduced, for example by reducing the duration of the condensation to 2.25 hours (resol F), resols are obtained which, when subsequently deionized as described herein, are capable of foaming to give a low density foam.

  
  <EMI ID = 204.1>

  
13) By adjustable pour-in-place reactions. The data also shows that when it is desired that the resoles of the invention form a higher density foam, such resols can be obtained by carrying out the condensation reaction under a harsher combination of conditions, such as times. condensations of 4.25 hours and 5.25 hours, having served to prepare the condensate products

  
tion from which resols D, E and G. are derived. the reason for the apparently abnormal result of Example 12-3, obtained from the resol E-3 having undergone an aging, is not obvious in view of the results obtained with Aging Resol D-3 which was used in Example 11-3. Resol D-3 has a significantly higher viscosity (64,500 cPo) after 15.5 hours

  
  <EMI ID = 205.1>

  
reactivity, as shown by the density of
36.1 g / dm <3> of the foam produced from this resol D-3.

  
  <EMI ID = 206.1>

  
For comparison, two resols were prepared which do not fall within the scope of the present invention, by treating a phenol-formaldehyde condensation product (factor of

  
  <EMI ID = 207.1> of 2.65 * However, instead of the subsequent treatment with an anion exchange resin, the final pH of the resole is brought to 4.7 by neutralization with alkaline condensation catalyst.

  
These particular resols are designated, here as being the resols

  
  <EMI ID = 208.1>

  
is interesting about these particular resolutions. This aforementioned patent relates to the preparation of phenol-formaldehyde resins obtained by reaction catalyzed by a base and having a duration

  
  <EMI ID = 209.1>

  
meaning then "a resin solution which remains water-soluble, without precipitation or gelation, for a long period.

  
  <EMI ID = 210.1>

  
resols having such a "water tolerance", the aforementioned patent suggests reducing the proportion of alkaline substance originating from the catalyst used for the condensation reaction (phenolformaldehyde) by treating this condensation product with a cation exchange resin to adjust the pH to a value between 4 and 8, by adjusting the duration of exposure to the cation exchange resin or "by bringing the pH to a

  
value less than 4 with subsequent addition of a substance

  
  <EMI ID = 211.1>

  
The alkaline substance that is added may be the same as that originally used to catalyze the condensation reaction, or a "volatile alkaline substance" such as an amine may be used. Although the aforementioned patent does not care

  
of the possible storage time of the resols from the point of view of their reactivity as foamable compositions, it was nevertheless advantageous to prepare and determine the aging characteristics of the aforementioned resols II and III.

  
More particularly, for the preparation of resols II and III, reaction mixtures containing the following constituents were used: 1600 g, ie 17 moles of phenol; 34 moles of formaldehyde, added as 2740 g of a solution

  
  <EMI ID = 212.1>

  
hydrated as catalyst and 230 g of distilled water. We heat

  
  <EMI ID = 213.1> 4.25 hours (resol III). After addition of barium hydroxide
(catalyst), the reaction mixtures have respective pH values of 8.65 and 8.75. After partial dehydration
(65.6 and 63.3 g of distillate per 100 g of phenol, respectively), the reaction mixtures have a pH of 7.8 (resol II)

  
  <EMI ID = 214.1>

  
with each resol and with 1000 g of cation exchange resin A, up to. that the pH stabilizes at 2.65. In each test, the pH of the resol is adjusted to a value of 4.70 by the addition of 38 g (resol II) and 40 g (resol III) of a solution.

  
  <EMI ID = 215.1>

  
then resol water at 45 [deg.] - 65 [deg.] C under a pressure corresponding to 80-45 mm of mercury, over a period of about 4 hours.

  
The liquid products, called resols II and III, are obtained with

  
yields of about 141 g per 100 g of phenol, and subjected to heat aging under nitrogen at 65 [deg.] C to.

  
atmospheric pressure, following the procedure described

  
  <EMI ID = 216.1>

  
times indicated in Table IV below. The latter table also indicates the viscosity of the resols after their preparation and after each aging period. Samples of the aged products are then used as the resol component of formulation A for producing a foam.

  
  <EMI ID = 217.1>

  
above for foaming. The following Table IV also provides data on foaming.

  

  <EMI ID = 218.1>


  

  <EMI ID = 219.1>


  

  <EMI ID = 220.1>
 

  
The results in Table IV show that the adjustment of the pH of the cation-exchanged condensation product by further addition of the alkali metal-based condensation catalyst, as in the preparation of resols II and III, adversely affects the characteristics. aging and processability of the product resol. Thus, after a total aging period of 13 hours (test C-2b), the

  
  <EMI ID = 221.1>

  
the sole resol component of formulation A for producing a foam. This latter conclusion is based on the observation that although some reactivity is indicated by a 7.5 cm lift in some areas of the foaming formulation, the foaming behavior is not. satisfactory; the high viscosity (147,000 cPo) may also explain why Resol II-2 does not foam. On the contrary, as shown by the series of aging data from the example

  
ple 4 of Table II, the deionized resol A of the invention, which

  
was also condensed at a formaldehyde factor of 170 for 3.25 hours at 75 [deg.] C and which was brought to a final pH

  
4.7 (by treatment with an anion exchange resin) a

  
superior aging characteristics and has a significantly lower initial viscosity which, although increased during aging, still remains at a value allowing the use of the resol. In addition, Resol III, which was prepared with the greatest condensation period of 4.25

  
  <EMI ID = 222.1>

  
(ning Resol D of Example 7) has such a high initial viscosity (552,000 cPo) that it cannot foam when using

  
the normal formulation A for producing a mousse, and becomes a material, similar to caramel (viscosity greater than

  
1,000,000 cPo) after only 7 hours of hot aging. On the contrary, and as shown by the data of Example 11 of Table III, Resol D of the present invention has

  
good aging characteristics and good reactivity for the production of a foam.

  
Examples _ 1 5-18

  
  <EMI ID = 223.1>

  
According to these examples, additional phenol-formaldehyde condensation products are prepared at times of

  
  <EMI ID = 224.1>

  
substantially as described above with respect to resols A to G except that, instead of carrying out the condensation at a formaldehyde factor of 170, this factor is about 120, in the case of a 37.3 solution % by weight of formaldehyde. More specifically, here are the starting materials in each preparation:
1882 g (20 moles) of phenol, 2413 g of an aqueous solution
37.3 &#65533; by weight of formaldehyde (30 moles of HCHO) and 32.3 g

  
  <EMI ID = 225.1>

  
188 g of distilled water. After addition of the aqueous solution

  
catalyst, the reaction mixtures have respective pH values of 8.80; 8.85; 8.75 and 8.70. We condense them

  
  <EMI ID = 226.1>

  
(resol H), 4.25 hours (resol J), 5.25 hours (resol K) and 6.25 hours (resol L). The condensation products are then subjected to partial dehydration at 45-65 [deg.] C under a pressure corresponding to 80-45 mm Hg, until the water content is brought to a level of about 25% in Hg. weight. A suspension is then formed, at room temperature, with the partially dehydrated products of this condensation and 1000 g of cation exchange resin A, and the mixture is stirred for 40 to

  
45 minutes during which the pH decreases to the values indicated in Table V below. After filtering off the cationic resin, the filtrates are combined with

  
300 g of the anion exchange resin A, and the resulting suspensions are stirred until the respective pH values are 4.55 to 4.6, as also shown in the table.

  
  <EMI ID = 227.1>

  
filtrates then having the pH indicated in Table V below.

TABLE V

  

  <EMI ID = 228.1>


  
An additional quantity of water is evaporated from the

  
  <EMI ID = 229.1>

  
about 40 mm) in a period of 6 hours (resols H and J), 4 hours
(resol K) and 3.75 hours (resol L), after which the filtrates are allowed to cool to room temperature. Its viscosity and its behavior during foaming are determined, both before and after hot aging, by operating as described in the following examples.

Example 19-22

  
  <EMI ID = 230.1>

  
  <EMI ID = 231.1>

  
for various periods of time, depending on the modus operandi of the game
(A) Examples 4-6 above. Before and after each aging period, samples were used as the resol component of a foaming formulation A (Table I) following the procedure described under part (B) of Examples 4-6. The following Table VI indicates the length of each heating period, the results of the viscosity measurements and the data regarding the reactivity during the production of a foam.

  

  <EMI ID = 232.1>


  

  <EMI ID = 233.1>


  

  <EMI ID = 234.1>
 

  
Examination of the results presented in Table VI shows that when the condensation reaction is carried out at a phenol-formaldehyde factor of 120, condensation times of 3.25 hours and 4.25 hours (such as They are used for the preparation of resols H and J), highly reactive resols having a low viscosity. The high reactivity of H and J resols is reflected, in particular, in the low density of the foams produced. Despite their high reactivity, the H and J resols allow an adjustable foaming reaction to take place at room temperature after discharge.

  
in place. The K and L resols were also condensed to a phenol-formaldehyde factor of 120, but over longer periods of condensation (5.25 hours and 6.25 hours). Resols

  
  <EMI ID = 235.1>

  
hot, but their viscosity increases markedly after hot aging. the high viscosity of these particular resols prevents proper incorporation by mixing of the acid

  
  <EMI ID = 236.1>

  
thus, although only a small shrinkage is observed, the overall rise of the foam is irregular and the foams have a poorer quality than the foams obtained from resols H and J. It is therefore evident that when the condensation reaction is carried out at 75 [deg.] C and with a formaldehyde factor of
120, prolonged periods of condensation should be avoided
(5.25 hours-6.25 hours).

  
Examples 23-33

  
According to these examples, phenolformaldehyde resols, designated herein as being resols M to W, at a

  
  <EMI ID = 237.1>

  
the following constituents are used: 1600 g of phenol;

  
2740 g of a 37.3% by weight aqueous solution of formaldehyde; and a catalyst solution containing potassium hydroxide (purity: 86.2%) dissolved in 188 g of distilled water.

  
The particular amount of potassium hydroxide and the condensation conditions employed in each preparation are shown in Table VIII below. By following substantially the same operating procedure of the manipulations as that described, for example, in Example 1, the respective condensation products are subjected: to partial dehydration; treatment with cation exchange resin A; filtration; treatment with anion exchange resin A; filtration;

  
and evaporation to remove additional aqueous distillate. Table VIII also indicates the amount of ion exchange resins that are used and the pH of the filtrates after each ion exchange treatment. The viscosity of each resole is measured and at least one resole prepared at the various

  
  <EMI ID = 238.1>

  
Each of the resols M to W is then used as a resol in the following formulation for preparing a foam:

TABLE VII

  
Formulation B for the preparation of a mousse

  

  <EMI ID = 239.1>


  
(1) as defined in Table I.

  
The foams are prepared by following the procedure

  
  <EMI ID = 240.1>

  
VIII below indicates the density of the respective foams produced, as well as the other aforementioned data.

  

  <EMI ID = 241.1>


  

  <EMI ID = 242.1>
 

  

  <EMI ID = 243.1>


  

  <EMI ID = 244.1>
 

  
(1) At reduced pressures corresponding to the following values

  
(in mm of Hg) at the respective temperatures:

  
  <EMI ID = 245.1>

  
(3) Up to a final reduced pressure corresponding to 40-41 mm

  
at 65-67 [deg.] C.

  
(4) Not registered.

  
It is evident from the data in Table VIII as well as from the data in Tables II, III and VI, that the process of the present invention offers multiple possibilities for the preparation of phenol-formaldehyde resols which are suitable for producing low-grade foams. vclumic mass and foams

  
at high density, thanks to. an appropriate adjustment of the conditions of the condensation and in particular of the formaldehyde factor, of the duration and of the temperature of this condensation, as well as of the concentration of the catalyst. Thus, as discussed in connection with the data in Table III, at a formaldehyde factor of 17C, a condensation temperature of 75 [deg.] C and a concentration of potassium hydroxide (catalyst) of about 2% by weight per with respect to phenol, highly reactive resols are obtained, allowing the formation of a low density foam, when operating with a relatively short condensation time (for example 2.25 hours), whereas one obtains resols to provide a higher density foam when operating at a longer condensation time (3.25 hours).

   As shown by the data in Table VI, highly reactive resols can also be prepared for the formation of a low density foam when operating with longer condensation times.
(eg 3.25 hours-4.25 hours), lowering the formaldehyde factor to 120. Further, the data in Table VIII indicate that foams having the desired density can be obtained by appropriately adjusting the condensation temperature and / or the concentration of the catalyst. In addition to their excellent reactivity when freshly prepared, the resols M to W of the present invention, which have undergone ion exchange, also have excellent aging characteristics, as illustrated by the results of Examples 34 to.
40 below.

  
Examples 34 and 35

  
The Q and R resols prepared under the conditions of Examples 27 and 28 (Table VIII) are subjected to hot aging at 65 [deg.] C and at atmospheric pressure under nitrogen for a total period of 18 hours in three stages of five, six and seven hours. After each stage of hot aging, the respective resolves are analyzed to determine

  
  <EMI ID = 246.1>

  
sity and the behavior thereof during foaming is verified by using formulation B for producing a foam (Table VII). The results obtained are shown in the following Table IX which, for easy comparison, also includes the corresponding values for each freshly prepared resol.

  

  <EMI ID = 247.1>


  

  <EMI ID = 248.1>
 

  
The results of Example 34 show the excellent retention of the high reactivity of resole Q as a foamable product, after accelerated aging. This is reflected by the fact that the time of formation of a cream, the time of rising,

  
the height of the lift and, in particular, the density of the foam, hardly changed after each period

  
of aging. Resol R also shows excellent aging characteristics. Retention of responsiveness

  
and the stability to self-condensation exhibited by Q and R resols is also reflected in the observation that their water contents remain relatively low.

  
It is also worth noting an observation that,

  
if the viscosity of the resin increases with aging,

  
the reactivity of freshly prepared and aged resols remains at approximately the same level.

  
This indicates that the increase in viscosity during aging of the resols of the present invention, treated by ion exchange, is not due to a significant self-condensation giving a higher molecular mass and giving less reactive polymers, but is rather due to a physical phenomenon

  
such as intermolecular bonding which, in the presence of the added acidic curing catalysts, easily cleaves or breaks to release highly reactive sites allowing rapid curing providing phenolic foam.

The other resolutions of the invention, such as the receipts

  
A, C and D described above show substantially the same tendency for good retention of their reactivity after hot aging, despite a significant increase in viscosity during accelerated aging. This is graphically illustrated by the accompanying Figure 1, which shows a correla-

  
  <EMI ID = 249.1>

  
  <EMI ID = 250.1>

  
se (in g / dm, on the ordinate) and the number of hours of hot aging for resols A, C, D and R according to the invention,

  
which have undergone ion exchange treatment, and for normal resol I, which does not constitute a product of the present invention.

  
For each resol, the numbers in parentheses correspond to the total number of hours during which the

  
  <EMI ID = 251.1>

  
and curve A) and Examples 6 to 6-3 (resol C and curve C) of Table II and Examples 11 to 11-3 (resol D; curve D) of Table III (in each of these examples the formulation

  
A for producing a foam); and Examples 35 to 35-3 (resol R and curve R) of Table IX, where formulation B for producing a foam was used. As shown by the curves corresponding to the esols of the invention, the reactivity of the resols, reflected by the density of the foam obtained, remains relatively constant despite the significant increase in viscosity. On the contrary, the reactivity of resol I, as a resol component of formulation A for producing a foam,

  
is significantly reduced after only 5 hours of heat aging (which is reflected by an increase of more

  
  <EMI ID = 252.1>

  
as well as after 18 hours, or at a level allowing the resols of the invention to have good reactivity and to be

  
  <EMI ID = 253.1>

  
reed in Figure 1).

  
Examples 37-40

  
According to these examples, the characteristics

  
aging at ambient conditions for M resols,

  
P, S, T and W, which were prepared as described in the examples
23, 26, 29, 30 and 33 of Table 7111. Simply store each resole at room temperature in a closed container.

  
and, after an extended period of storage, samples are taken for viscosity measurements and for testing

  
behavior during foaming, using formula B for preparing a foam (Table VII). The number of days for this aging, the viscosity and the foaming characteristics after aging are shown in Table X, which also includes the corresponding initial data.

  

  <EMI ID = 254.1>


  

  <EMI ID = 255.1>
 

  
The data in Table X further show the excellent storage capability of the resols of the present invention treated by ion exchange. To determine if the resols M, F, S,

  
T and W retained any reactivity to serve as foamable resins after an extremely prolonged period of time, the foaming reactivity of each resol serving as the resol component in formulation B for producing a foam was checked,

  
  <EMI ID = 256.1>

  
ment to ambient conditions in addition to the number of days? aging times indicated in Table X. The following Table XI indicates

  
viscosity, water content and reactivity data for each resol after the indicated aging period.

TABLE XI

  

  <EMI ID = 257.1>


  
(1) not measured

  
the above data show quite surprisingly that despite the fact that these resols have undergone aging at ambient conditions for periods almost equal to 2 years or even greater, these resols have retained sufficient reactivity and fluidity to be able to foam. The foam produced from the resol T having undergone this aging is

  
  <EMI ID = 258.1>

  
density of the foam produced is 23.44 g / dm.

Example 41

  
Preparation of resol X and reactivity for foaming

  
In the present example, an additional liquid resole is prepared according to the invention, with a formaldehyde factor <EMI ID = 259.1>

  
formaldehyde) in the presence of 16 g of potassium hydroxide
(catalyst; purity: 85.9%) dissolved in 188 g of distilled water, for a period of 3.25 hours at 85 [deg.] C (pressure corresponding to 480 mm-525 mm Hg). After the condensation reaction, the pH of the condensation product (cooled to 45 [deg.] C) is 7.7. A suspension is then formed with the condensation product (4490 g) and with 350 g of the cation exchange resin A, until the pH of the suspension stabilizes at 2.5, which takes about 16 minutes. The suspension is then filtered and the filtrate is combined with 1000 g of the anion exchange resin A for about 40 minutes. After this period, the pH of the suspension is 5.45.

   Separated by filtration. the anion exchange resin and 2216 g of aqueous distillate are removed by evaporation of this filtrate at about 48-51 [deg.] C (at a pressure corresponding to 100-85 mm Hg) and finally, at 65 [deg.] C at a pressure corresponding to 15 mm of Hg. The remaining liquid product
(2130 g), referred to herein as resole X, has a Brookfield viscosity at 25 [deg.] C of 66,000 centipoise and a water content of

  
  <EMI ID = 260.1>

  
Following the general foaming procedure described above, resole X is employed as the resol component of formulation B for producing a foam of Table VII. Here are the data concerning the foam production reactivity: time until a cream forms: 20 seconds; rising time: 100 seconds; time until no state

  
  <EMI ID = 261.1>

  
density of the foam: 26.2 g / dm <3>. The compressive strength, and the resistance to friability of the foam produced are shown in. table XVII below.

Example 42

  
According to the present example, the resol X, prepared according to Example 41 above, is subjected to a normality test to determine its gel time, that is to say the time necessary for the resol to reach a degree of polymerization such that it has become a gel. For comparison, the gel time of a phenol-formaldehyde resole, designated here, is also determined.

  
  <EMI ID = 262.1>

  
When making resole I-A, the condensation of phenol and formaldehyde is carried out using barium hydroxide octahydrate as a catalyst, and the condensation product is neutralized with dilute sulfuric acid. As originally prepared, Resol I-A has a pH of 6.8, a water content of 7.0 wt% and a viscosity of 2970 centipoise. Resol I-A can react strongly to heat under ordinary conditions

  
storage and therefore it is normally recommended to keep it

  
  <EMI ID = 263.1>

  
tion of their respective gel times, the resol 1 of the invention was stored at room temperature for approximately 43 days, and the rescl I-A was stored under refrigeration.
(about 5 [deg.] C). As used in this example, the resol

  
  <EMI ID = 264.1>

  
ratory. In each determination, a sample of

  
1 g of resol in the center of a hot plate set at 100 [deg.] C, at
1300C, at 150 [deg.] C and at 180 [deg.] C, respectively. After an interval

  
30 seconds, the sample is struck with a spatula and the end point of the test is considered to be the time necessary for the sample to reach a state of polymerization characterized by the start of sticking and the formation of "threads" polymer
(that is, the time it takes to reach a sticky state). A number of measurements are made for respective samples of each resol at the indicated temperatures. Gel time measurements are made to determine relative cure rates. The longer the gel time, the more stable the resole is to polymerization which causes it to change to the fully cured (thermoset) state. The results obtained are presented in Table XII below.

TABLE XII

  

  <EMI ID = 265.1>


  
  <EMI ID = 266.1>

  
The results of Table XII show the increase in the inherent stability with respect to self-condensation of the resols of the invention, treated by ion exchange, in comparison with commercial resols supplied in the form of mousstable compositions. . Despite their better stability and their possible extended shelf life, the resols of the invention also have a greater reactivity of foamable composition compared to the resols used in industrial practice for the manufacture of a rigid phenolic resin of medium density by foaming reactions with pouring in place.

   As shown by the reactivity data for the production of a foam (Table II), in the case of the use of formulation A of Table I for the preparation of a foam, the resol I (which is not obtained according to the present invention) provided in comparative test C-1

  
  <EMI ID = 267.1>

  
volume of approximately 45.4 g / dm <3>. On the contrary, from the same formulation A, the resols A to C of the invention provide foams having markedly lower densities both before and after accelerated aging, these lower densities reflecting their better reactivity as foamable compositions. The greater reactivity of the resols of the invention, treated by ion exchange, is further indicated by the observation that these resols require less catalyst to obtain a foam of a given density than the comparative resols.

  
  <EMI ID = 268.1>

  
as the resol component of formulation B for producing a foam, however modified to contain 24 parts of the acid catalyst instead of only 9 parts, the formation times

  
cream and leaven are 50 seconds and 130 seconds, respectively; the foam lift height is 18.75 cm and the resulting foam has a density of 25.9 g / dm, this

  
which is close to the density of 26.2 g / dm3 of the foam produced from reaol X of Example 41 with the lowest concentration of 9 parts of fluoboric acid as catalyst. Likewise, when Comparative Resol IA is employed as the resole component of formulation B for producing a foam, modified to contain 21 parts of the acid catalyst and 40 parts of the blowing agent, the foaming reactivity is : cream formation time: 80 seconds; rising time: 240 seconds; foam lifting height: 16.25 cm; density

  
  <EMI ID = 269.1>

  
sound with terms used commercially and provided

  
  <EMI ID = 270.1>

  
  <EMI ID = 271.1>

  
by ion exchange, possess, as a foamable composition, a greater inherent reactivity because the resols according to the invention provide a foam having a particular density or density at lower levels of: The concentration of the catalyst.

Example 43

  
Preparation of Resol Y

  
The present example illustrates the preparation of the resols of the invention on the scale of a pilot installation, when the deionization is carried out in fixed beds of exchange resins in columns. Condensation is carried out in a stainless steel reactor equipped with a condenser and

  
  <EMI ID = 272.1>

  
formaldehyde being approximately 170, and 5.22 kg of an aqueous solution (approximately 12.5% by weight) of potassium hydroxide (purity:

  
  <EMI ID = 273.1>

  
by the reaction causes reflux and the temperature is adjusted to 85 [deg.] C for 3 hours by adjusting the pressure (corresponding

  
  <EMI ID = 274.1>

  
of the reaction, it is passed through a drum, then passed in a downward direction through a 45.4 kg bed of cation exchange resin A, contained in a coated tower

  
  <EMI ID = 275.1>

  
the effluent from the cation exchange tower has a pH of 3.0 and is then passed downward through a 72.6 kg bed of the anion exchange resin A, contained in a stainless steel tower (24-4- cm x 30 cm internal diameter). The effluent from the anion exchange tower has a pH of 5.2 and 47.4 kg of aqueous distillate are removed therefrom by operating under pressure.

  
  <EMI ID = 276.1>

  
the resol thus produced, designated as being the resol Y, with

  
a yield of 134 kg per 100 kg of phenol used and, on analysis, this resole was found to have a water content of 5.78%

  
by weight and a Brookfield viscosity (at 25 [deg.] C) of 22,800 centipoise.

  
The reactivity of resol Y as resin is determined before and after aging for 54 days at room temperature.

  
  <EMI ID = 277.1>

  
freshly prepared and material aged to be the resol component of formulation B for preparing a mousse (Table VII). The results obtained are presented in. table XIII.

TABLE XIII

  

  <EMI ID = 278.1>


  
(1) After 54 days of aging at room temperature.

  
The results of Table XIII further show the excellent storability of the resols of the invention,

  
  <EMI ID = 279.1>

  
ves of mousses prepared from freshly prepared resol Y

  
and after aging of this resol Y, are substantially the

  
same. Note also the observation that,

  
although the viscosity of the aging material increased considerably, this did not affect the reactivity.

Example 44

  
Preparation of Resol Z,

  
  <EMI ID = 280.1>

  
By following substantially the same operating mode of the manipulations and using the equipment described in the example
43, a highly reactive resole is prepared which is suitable for spray application of a phenolic resin, as described below,

  
The condensation reaction is carried out using
77.6 kg of phenol and 133 kg of 37% aqueous formaldehyde solution (the formaldehyde factor being approximately 170) and approximately

  
  <EMI ID = 281.1>

  
7 dissolve in 3.7 kg of distilled water. We reduce the pressure

  
prevailing over the system at a value corresponding to approximately
400 mm Hg and, after the initial release of heat by the reaction, the temperature is adjusted to 75 [deg.] C for about 3 hours by adjusting the pressure (so as to correspond to 400-
470 mm Hg) The reaction product is then cooled

  
  <EMI ID = 282.1>

  
passes this product downwardly through a 45.4 kg bed of cation exchange resin A, contained in the tower described in Example 43. The effluent from the exchange tower

  
cations has a pH of 2.2 and is passed downward through a bed of the anion exchange resin A contained in the stainless steel tower. The effluent from the exchange tower

  
anions has a pH of 4.7, and is removed from the aqueous distillate

  
  <EMI ID = 283.1>

  
of Hg and 54-63 [deg.] C). We obtain the resol thus produced, designated

  
here as being "resol Z", with a yield of 132 kg for
100 kg of the phenol used. On analysis, Resol Z was found to contain 1.90% by weight of water and to have a Brookfield viscosity (at 25 [deg.] C) of 860 centipoise. Resol Z is highly reactive and therefore suitable for use in forming a phenolic resin with

  
  <EMI ID = 284.1>

  
spray cation, when a spray apparatus such as that disclosed in US Pat. No. 3,122,326 is employed. Resol Z is also suitable for mixing with less strongly resols. reagents according to the invention in order to satisfy a particular specification relating to the density of the foam to be obtained.

Example 45

  
An aging study was carried out on the resole Z by keeping a portion thereof in a closed glass container, 3.78 l capacity, under static conditions at room temperature (mean 23 [deg.] - 26 [deg. ]VS). A sample of the resol subjected to this aging is periodically taken, during a total aging period of about 16 months, and the sample is subjected to. a water content analysis and a viscosity measurement. About a month after the start of aging of the resole Z, the same operating mode is applied to a phenol-formaldehyde resole used on an industrial scale, and which is designated here as being the comparative resole IV which is also intended to manufacture a phenolic foam with very low density (3.2 to 4.8 g / dm <3>).

   Resol IV is produced at a formaldehyde factor of about 120 (based on a 37% aqueous solution of formaldehyde), with the use of barium hydroxide as a catalyst to effect the condensation reaction and, as in. the case of comparative resolutions I and IA,

  
the condensation product is neutralized by adding sulfuric acid to it, the resulting barium salt being left in

  
  <EMI ID = 285.1>

  
has a pH of 6.3 and a viscosity of 743 centipoise. To maintain a good possibility of foaming, it is normally recommended that Resol IV be stored at a lower temperature.

  
  <EMI ID = 286.1>

  
of 24 [deg.] C storage if such storage does not exceed 3 months. Prior to the time when resol IV was subjected to this aging study, this resol IV was kept under refrigeration. When resol IV was started to age at ambient conditions, this resol IV had a water content of

  
  <EMI ID = 287.1>

  
tipoises. The results obtained are shown in Table XIV.

  

  <EMI ID = 288.1>


  

  <EMI ID = 289.1>
 

  
The results of this aging study
(i.e. the data in Table XIV) form the basis of the accompanying Figures 2 and 3 which show the variation in water content (Figure 2; percentage by weight of water content on the ordinate) and viscosity (Brook viscosity-

  
  <EMI ID = 290.1>

  
ment (on the x-axis in Figures 2 and 3: aging period at ambient conditions). Examination of these respective figures shows the substantially constant level of water and of the viscosity during the aging of the deionized product (resol Z) according to the invention, in comparison with the resol IV employed on an industrial scale and which is intended to provide the same quality

  
of phenolic foam. the strong increase in viscosity of resol IV during periods 14 and 15 of its aging is

  
too large to be shown in Figure 3, due to the scale used for viscosity; these specific values are provided in Table XIV. The relatively constant level

  
of the water content of resol Z, during this prolonged study

  
aging at ambient conditions for about 16 months, further indicates the remarkable inherent stability of the resols

  
  <EMI ID = 291.1>

  
higher molecular weight and resulting in less reactive resins.

Example 46

  
Preparation of resol XX and reactivity for foaming.

  
In the present example, another liquid resole according to the invention is prepared, by operating substantially in the same way and under the same conditions as for the resole X of example 41 above. Thus, the condensation reaction is carried out at a formaldehyde factor of 170 (1600 g of phenol and 2740 g of a

  
  <EMI ID = 292.1>

  
dissolved in 188 g of distilled water for a period of

  
  <EMI ID = 293.1>

  
After the condensation reaction, the pH of the condensation product (cooled to 45 [deg.] C) is 7.7. A suspension is then formed with the product of this condensation (4522 g) and with 350 g of cation exchange resin A, until the pH of the suspension stabilizes at 2.5, which takes approximately 14 minutes. The suspension is then filtered and the filtrate is combined with 1000 g of anion exchange resin A for about 32 minutes. After this period, the pH of the suspension is

  
5.45. The anion exchange resin is separated by filtration and the filtrate is subjected to evaporation from an aqueous distillate.

  
  <EMI ID = 294.1>

  
the remainder (1990 g), referred to herein as XX resol, has a Brookfield viscosity at 25 [deg.] C of 85,000 centipoise and a water content of 1.25% by weight.

  
By following the general foaming procedure described

  
  <EMI ID = 295.1>

  
formulation B for preparing a foam of Table VII. Here are the data concerning the reactivity for obtaining a foam: cream formation time: 18 seconds; rising time: 90 seconds; time until no sticky state:

  
80 seconds; foam lifting height: 19 cm; mass

  
  <EMI ID = 296.1>

  
includes an indication of the compressive strength and the resistance to crumbling of the foam thus produced.

  
  <EMI ID = 297.1>

  
According to these examples, a series of 4 additional phenol-formaldehyde resols are prepared according to the invention, designated here as being the AA, BB, CC and DD resols, at a formaldehyde factor of 170 (1600 g of phenol and 2740 g of 'a solution

  
  <EMI ID = 298.1>

  
potassium (catalyst having the quality of the product obtained in a cell with a mercury cathode) dissolved in 188 g of distilled water. The potassium hydroxide employed for each preparation is that available commercially in flake form from Hooker Chemical Corporation under the

  
  <EMI ID = 299.1>

  
Company, has the following specifications (dry form):

TABLE XV

  

  <EMI ID = 300.1>


  
To prepare the AA and BB resols, the condensation reactions are carried out for 3 hours and 15 minutes at 85 [deg.] C

  
  <EMI ID = 301.1>

  
To prepare the CC and DD resols, the condensation reactions are carried out for 3 hours and 20 minutes at 85 [deg.] C under reduced pressure corresponding to 460 mm-510 mm Hg (CC resol) and

  
  <EMI ID = 302.1>

  
of condensation, the pH of the respective hot condensation products (at about 35 [deg.] - 45 [deg.] C) is measured. Each of the individual condensation products and cation exchange resin A is then formed into a suspension until the pH of

  
the suspension had lowered to 2.7 2,7 2.75. After filtration, a suspension is formed with the cation-exchanged filtrates and with anion-exchange resin A until

  
that the pH of the respective mixtures be raised to 5.5. The products having undergone this ion exchange are then subjected to evaporation of an aqueous distillate at an elevated temperature and under a reduced pressure. The conditions of this purification evaporation are 50 [deg.] C-54 [deg.] C under a pressure corresponding to 115-100 mm Hg (resol AA); 51 [deg.] - 54 [deg.] C under a pressure corresponding to

  
  <EMI ID = 303.1>

  
laying at 105-60 mm Hg (resol CC) and 50-55 [deg.] C under a pressure corresponding to 105-70 mm Hg (resol DD). The final state of each evaporation operation is 65 [deg.] C under a pressure corresponding to 40 mm of Hg. Table XVI below indicates the viscosity.

  
  <EMI ID = 304.1>

  
the ion exchange resins used, the pH of the condensation products initially and after each stage of ion exchange, the amount of aqueous distillate collected and the product yields. The following Table XVI also includes the corresponding data for resol X (example 41) and resol XX
(Example 46) described above.

  
t;

  

  <EMI ID = 305.1>


  

  <EMI ID = 306.1>
 

  
Examples 51-54

  
In these examples, phenolic foams are prepared by employing resols AA, BB, CC and DD described above of Examples 47-50 as the resol component of formulation B

  
for preparing a mousse, which is defined in Table 711.: For these preparations, the general foaming procedure is followed

  
  <EMI ID = 307.1>

  
foams produced. The compressive strength is measured according to the procedure of ASTM D-1621. Resistance to friability was measured using a combination of ASTM C-367 and barrel tumbling tests according to 0-421. That is, the test samples are conditioned at room temperature in red oak cubes according to ASTM C-367, and the test time intervals
(after periods of 2 and 8 minutes for a total of 10 minutes)

  
correspond to ASTM C-421. Table XVII also includes data on the reactivity of Resol X and Resol XX described in Examples 41 and 46, respectively, as well as data on compressive strength and strength.

  
&#65533; the friability of the foams which derive from these resols. Here is Table XVII.

  

  <EMI ID = 308.1>


  

  <EMI ID = 309.1>
 

  
The results of Table XVII show that the phenolic foams produced using resols AA, BB, CC and DD show a marked improvement in the resistance to friability compared to the resistance of the foams produced from resols X and XX, the essential difference between the two

  
  <EMI ID = 310.1>

  
potassium, a quality originating from the mercury cathode cell (90% purity) used to manufacture the condensation products from which the AA-DD resols are derived, are given in Table XV which follows Examples 47 to 50 above. The potassium hydroxide used in the preparation of each of resols X and XX is that supplied by JT Baker and Company under the designation "Potassium Hydroxide Pellets," Baker Analyzed "Reagent" (potassium hydroxide pellets, reagent "analyzed by Baker ").

  
As indicated in the container containing the pellets supplied by J. T. Baker and Company, the analysis of batch n [deg.] 45240 is that indicated in the following Table XVIII:

TABLE XVIII

  

  <EMI ID = 311.1>


  
From the analysis provided by the manufacturer and shown in Table XVIII, it is not clear how

  
: and particular potassium hydroxide was manufactured. However, <EMI ID = 312.1>

  
it appears that this hydroxide was not made in a mercury cathode cell. In any case, the following Table XIX gives the analyzes of the two types of potassium hydroxide by emission spectrometry and by ray fluorescence.

  
  <EMI ID = 313.1>

TABLE XIX

  

  <EMI ID = 314.1>


  
(1) Hooker Chemical Corporation; supplied as glitter

  
serving as a condensation catalyst for the preparation

  
AA-DD resols.

  
(2) J. T. Baker and Company; supplied in the form of lozenges;

  
serving as a condensation catalyst for the preparation of resols X and XX.

  
Despite the various analyzes given in Tables XV, XVIII and XIX above, as previously indicated here, the exact reason or reasons for the significant improvement observed in the resistance to friability of phenolic foams obtained from the resols of the invention (for example the AA-DD resols) originating from the products of the. Catalyzed condensation in the presence of potassium hydroxide (a quality from a mercury cathode cell) has not or has not been elucidated.

  
  <EMI ID = 315.1>

  
Preparation of Resol EE

  
According to the present example, an additional phenol-formaldehyde resole of the invention, designated here as being the resole EE, is prepared by operating at a formaldehyde factor of

  
  <EMI ID = 316.1>

  
formaldehyde) in the presence of 16 g of potassium hydroxide (quality from a cell with a mercury cathode) as a catalyst

  
  <EMI ID = 317.1>

  
Cell - Low Chloride "(caustic potash flake; cell

  
  <EMI ID = 318.1>

  
XX below gives the analysis of this material indicated by the manufacturer:

TABLE XX

  

  <EMI ID = 319.1>


  
The condensation reaction is carried out for

  
  <EMI ID = 320.1>

  
corresponding to 450-508 mm Hg. The condensation product is removed from the reactor and weighed (4528 g). This condensation product is then passed through a tower (7.0 cm inside diameter) containing 1300 ml of cation exchange resin A. The pH of the effluent is 2.9 after a residence time in the cation exchange resin bed of 14 minutes. The resol having undergone this cation exchange is then passed through a tower (8.0 cm internal diameter) containing
1400 ml of anion exchange resin A for a total time

  
  <EMI ID = 321.1>

Example 56

  
According to the present example, the resol EB of Example 55 is used as the resol component of formulation A for the preparation of a foam of Table I, using the procedure.

  
  <EMI ID = 322.1>

TABLE XXI

  

  <EMI ID = 323.1>


  
  <EMI ID = 324.1>

  
(2) For foam samples prepared for measurements

  
friability.

  
The data in Table XXI is based on a phenolic foam produced from substantially EE resol

  
  <EMI ID = 325.1>

  
water content: 1.4% by weight). After about 62 days of aging at ambient conditions, the Brookfield viscosity of the EE resole is 51,400 cPo at 25 [deg.] C and its water content is

  
  <EMI ID = 326.1>

  
days of aging at ambient temperatures, the resol EE

  
to an accelerated aging study. For this, 700 g of the resol which has already undergone aging under ambient conditions are placed in a 1 liter round-bottom flask, fitted with a thermometer, a stirrer and an adapter open to the atmosphere. The resole was heated to 65 ° C. while stirring slowly over a period of 5 hours. At the end of this period,

  
the resol which has undergone heat aging and which is designated

  
  <EMI ID = 327.1>

  
weight. According to the general foaming procedure described above, a foam is prepared by using 300 g of resol EE-1 as the resol component of formulation A for preparing a foam (Table I). The reactivity data are: time until cream formation: 60 seconds; rising time: 115 seconds; gel time: 80 seconds; and lifting height of the foam: 13.75 cm. The foam shrinkage is only 1.6mm. The friability of the foam is also measured according to the above normal procedures. Here are the results of these measurements: density of the foam samples prepared for the friability determinations: 43.7 g / dm <3>; percentage of weight loss: after 2 minutes, 4%; after 10 minutes,

  
  <EMI ID = 328.1>

  
warm temperature (65 [deg.] C), following the procedure applied during the initial period of. 5 hours, which includes slow stirring while the flask is open to atmosphere. After the total 18 hour period of accelerated aging, the resole (now referred to as EE-2 resole) has a Brookfield viscosity at 25 [deg.] C of 91,300 cPo and a water content of 3. , 26%. Following the general foaming procedure described above, a foam is prepared using the

  
  <EMI ID = 329.1>

  
treatment of a foam (Table I). Here are the data characterizing the reactivity: time until a cream forms: 100 seconds; rising time: 160 seconds; gel time
120 seconds; and lifting height of the foam: 11.25 cm. The foam shrinkage is only 1.6mm. Void formation is also observed which may be due to improper mixing of the forming ingredients, due to the relatively high viscosity of the EE-2 resole. However, despite the significant increase in viscosity and the rather difficult aging to which the EE-2 resole was subjected (i.e. 62 days of aging at ambient conditions followed by a total period of

  
18 hours of accelerated aging at 65 [deg.] C), the water content of this resol remains at a relatively low value (3.26% by weight), and this resol retains high reactivity as a foamable resol.

CLAIMS

  
1. Phenolic resols, characterized in that they do not contain ionic bodies which can be removed by the free acid form of a cation exchange resin and by the free acid form of an anion exchange resin .

  
  <EMI ID = 330.1>

  
extended storage time possible, characterized in that they do not contain ionic bodies which can be further removed by the free acid form of a cation exchange resin and by the free base form of an exchange resin. anions.

  
3. Foamable phenol-formaldehyde resols, having an extended storage period possible and characterized in that

  
  <EMI ID = 331.1>

  
weight and in particular a water content not greater than approximately

  
6% by weight, and in that they do not contain ionic bodies which can be removed by a strongly acidic cation exchange resin and by the hydroxyl form of an anion exchange resin.

  
4. Compositions comprising phenol-formaldehyde resols having a prolonged shelf life, these compositions being characterized in that the resols have been condensed in the presence of a catalyst derived from an alkali or alkaline earth metal for the condensation reaction of phenol and formaldehyde and in that the condensation products have been subsequently deionized by ion exchange with the free acid form of a cation exchange resin and with the free base form of a d exchange resin. anions.


    

Claims (1)

5. Compositions according to claim 4, characterized in that the alkali or alkaline earth metal-based catalyst is a potassium compound, a sodium compound or a cesium compound (alkali compounds) or a barium compound (compo se alkaline earth). 6. Foamable compositions, characterized in that they comprise phenol-formaldehyde resols having a water content of not more than about 10% by weight, these resols having been obtained by condensation of phenol and formaldehyde in the presence of potassium hydroxide as a catalyst and the products of this condensation having subsequently been subjected to deionization by treatment with a strongly acidic cation exchange resin and with a strongly basic anion exchange resin. 7. Process for the formation of phenolic resols, characterized in that a phenolic compound and an aldehyde is reacted in the presence of a catalyst derived from an alkali or alkaline earth metal under the conditions such as one forms an aqueous aqueous condensation product, and deionized this alkaline condensation product by treating this product with the free acid form of a cation exchange resin and with the free base form of an anion exchange resin. 8. Process for the formation of liquid phenol-formaldehyde resols having an extended shelf life, <EMI ID = 332.1> and formaldehyde in the presence of an alkali or alkaline earth metal catalyst under conditions such that an aqueous alkali condensation product is formed; this alkaline condensation product is treated with the free acid form of a cation exchange resin to reduce its pH <EMI ID = 333.1> treats the condensation product, the cations of which have already been exchanged, with the free base form of an anion exchange resin so that the pH is increased to a value between about 4 and about 7. 9. The method of claim 8, characterized in that the catalyst derived from an alkali metal or alkaline earth metal is an oxygenated mineral compound of potassium, in particular potassium hydroxide and in particular potassium hydroxide having the quality of the product obtained in a mercury cathode electrolysis cell. 10. The method of claim 8, characterized in that the cation exchange resin is a strongly acidic resin. 11. The method of claim 8, characterized in that the anion exchange resin is in the hydroxyl form. 12. The method of claim 8, characterized in that the pH of the alkaline condensation product is reduced to a value between approximately 2 and approximately 3.5 and in that it is substantially stabilized at such a value. <EMI ID = 334.1> phenol-formaldehyde having an extended shelf life, this process being characterized in that the phenol is condensed with at least an approximately equimolar amount of formaldehyde in the presence of potassium hydroxide as a catalyst, under conditions such as to form an alkaline liquid condensation product; this alkaline condensation product is brought into intimate contact with a strongly acidic cation exchange resin, under conditions such as the pH of the product. <EMI ID = 335.1> about 1.5 and about 4 and substantially stabilizes at such a value; the liquid which has undergone this cation exchange treatment is passed into intimate contact with a strongly basic anion exchange resin, under conditions such as pH increases to a value between about 4 and about 7 and stabilizes substantially at such a value, providing liquid product comprising deionized phenol-formaldehyde resols. 14. The method of claim 13, characterized in that the liquid product is obtained in substantially anhydrous form. 15. The method of claim 13, characterized in that the liquid product is obtained in the form of a solution. <EMI ID = 336.1> 16. The method of claim 13, characterized in that the pH of the liquid in contact with the cation exchange resin is substantially stabilized at a value between approximately 2 and approximately 3.5. 17. The method of claim 13, characterized in that the pH of the liquid in contact with the exchange resin <EMI ID = 337.1> about. 18. Process for the formation of foamable liquid phenolformaldehyde resols having a prolonged storeability, this process being characterized in that phenol and formaldehyde are condensed at a formaldehyde: phenol molar ratio. <EMI ID = 338.1> potassium at a condensing temperature of between about 65 [deg.] C and about 100 [deg.] C; the alkaline condensation product is brought into intimate contact with a strongly acidic cation exchange resin under conditions such that the pH of the condensation product decreases to between about 2 and about 3.5 and substantially stabilizes at a such value; the liquid which has undergone this cation exchange is passed into intimate contact with a strongly basic anion exchange resin under conditions such that the pH increases and stabilizes substantially at a value between about 4.5 and about 6, 5; and decreasing the water content of the liquid which has undergone this ion exchange treatment to a level not greater than about 10% by weight; then collecting the liquid phenol-formaldehyde resole having a water content of not more than about 10% by weight and which constitutes a product of this process. 19. The method of claim 18, characterized in that the potassium hydroxide is of the quality obtained in a mercury cathode electrolysis cell. 20. Liquid phenol-formaldehyde resin, characterized in that it is produced by the process according to one of claims 18 and 19. 21. The method of claim 18, characterized in that the water content of the liquid which has undergone the ion exchange is reduced to a level of not more than about 4% by weight, and in that the recovered resol has a content of water no <EMI ID = 339.1> 22. Cellular phenolic composition, characterized in that it has been produced by polymerization, in the presence of an acid polymerization accelerator and a swelling agent, of a deionized phenolic resole. 23. Phenolic foam, characterized in that it was produced by the polymerization of a deionized phenol-formaldehyde resole (having a water content of not more than about 10% by weight) in the presence of a strongly acidic accelerator of the polymerization, a blowing agent comprising a halogenated organic compound having a boiling point comprises <EMI ID = 340.1> 24. Phenolic foam, characterized in that it * was produced by polymerization, in the presence of a strongly acidic accelerator, a swelling agent and a surfactant, of a phenol-formaldehyde resole having no ionic body which can still be removed by the free acid form of a cation exchange resin and by the free base form of an anion exchange resin, this resol having a content of <EMI ID = 341.1> 25. Phenolic foam, characterized in that it was produced by polymerization (in the presence of a strongly acidic accelerator, a blowing agent comprising a halogenated hydrocarbon and a surfactant) of a phenolformaldehyde resole obtained by treatment of a condensation product <EMI ID = 342.1> cation exchange acid and a strongly basic anion exchange resin, this resol having a water content not <EMI ID = 343.1>