DE2344595A1 - METHOD FOR PRODUCING POLYURETHANE FOAMS AND POLYURETHANE FOAMS PRODUCED BY THE PROCESS - Google Patents

Description

PAT EN TA N W ALT E

DR. ING. A. VAN DERWERTH DR. FRANZ LEDERER

21 HAMBURG 9O 8 MÖNCHEN 80

WM.STORFER STR. S3 - TEL. CO «UI 770861 LUCILE-GRAHN-STR. 22 - TEL. 108 111 44 OS 46

23U595

Munich, August 7th 1973 Cas S.72 / 17 - 73/1 dive

SOLVAX & CIE.
33, Rue du Prince Albert, Brussels, Belgium

Process for the production of Polyurethanschäuinen and after Process produced polyurethane foams

Separation from patent application P 23 23 702.7

The invention relates to the production of Polyui'e thanschäum en using new, halogenated polyether polyols as well as Polyux * ethane foams produced by the process.

It is well known that rigid polyurethane foams are versatile and find different technical applications, especially in the fields of construction and insulation, in which fire resistance is a desired or even an indispensable property.

309882/1342

There are already several means of making polyurethane foams refractory Grant properties. A well-known method is to add fire protection additives such as antimony oxide or to the foams also halogen and / or phosphorus compounds such as the phosphates of tris (dibromopropyl) or tris (dichloropropyl), chlorinated Biphenyls and halogenated hydrocarbons to be added. These Additives that are not chemically bound to the base polymer can, however, have a permanent, evenly distributed one Cannot guarantee fire resistance. In addition, they generally have a softening effect on the foam and as a consequence, they lower the mechanical properties and in particular its compressive strength and dimensional stability.

Another way of making fire retardant polyurethane foams consists in halogenated and / or phosphorus-containing Use polyols.

In the French patent 1 350 4-25 is the use of halogenated polyether polyols described, which by adding epihalogenhydrins to monomeric, polyhydric alcohols, which contain at least two hydroxyl radicals. This addition reaction produces halogenated polyether polyols, which have a number of secondary hydroxyl functions that of the number of hydroxyl functions of the hydroxyl-containing Output respondent is the same. The result of the reaction of organic polyisocyanates with these halogenated polyether polyols Cellular polyurethanes derived from the invention exhibit certain durable and satisfactory refractory properties but their dimensional stability is generally insufficient. In addition, their manufacture difficult because of the low reactivity of these polyether polyols; this responsiveness is even less than that the corresponding, non-halogenated polyether polyols.

The object of the invention is to overcome these disadvantages.

309882/1342

23A4595

The invention relates to a method for producing rigid or semi-rigid, fire-resistant polyurethane foams.

According to this process, rigid or semi-rigid, non-flammable polyurethane foams are produced by the reaction of an organic one Polyisocyanate and at least one polyether polyol of the following general formula:

Z-f — f 0 -CH- CH,

CH ₂ Cl

- CH -

CH ₀ - CH - CH "

² I! ²

OH OH

where ζ is a number between 2 and 6, χ and y are numbers between 0 and 12, the mean value χ + y per chain being between 0 and 12 and ζ U + y) > where χ + y is the mean value of χ + y im whole molecule is between 1 and 72, and Z represents an organic radical with the valence ζ.

Chlorinated polyether polyols which are particularly preferred for the production of rigid, non-flammable polyurethane foams according to the invention correspond to the above general formula in which ζ denotes a number between 2 and 6, χ and y denote numbers between 0 and 4, the mean value χ + y per chain between 0 and 4 and ζ (, χ + j) , where χ + y is the mean value of χ + y in the entire molecule, is between 1 and 24, and Z is an organic radical with the valence ζ and C ₀ to C, - .

Such new polyether polyols are in the German patent application P 23 23 702.7 described by the applicant on the same day.

309882/1342

Very "especially for the production of rigid polyurethane foams preferred polyether polyols correspond to the general formula given above, in which ζ, κ and y have the meanings given above and Z is aliphatic, saturated or not saturated, halogenated radical with the valency S and C "to Cg represents where the halogen is chlorine or bromine.

The . - Enable halogen-based polyether polyols

the production of non-flammable polyurethane foams, which have similar or better mechanical properties to those of commercially available, non-halogenated polyether polyols.

The . - Halogenierten'Polyätherpolyole can be used alone or in a mixture for the production of polyurethanes.

The relative proportion of halogenated polyol

polyether in the mixture of polyether polyols used can vary to a fairly large extent. The self-extinction properties however, the higher this proportion, the better the polyurethanes obtained. Rigid, self-extinguishing Polyurethanes according to the ASTiI D 1692 standard can be used by using of mixtures of polyether polyols, which one or more non-halogenated polyether polyols and 4-0% by weight, preferably 70% by weight, of the least halogen-containing polyether polyols and contain only 20 to 35% by weight of the halogen-richest halogenated polyether polyols.

The rigid and semi-rigid polyurethane foams according to the invention are in a manner known per se by reacting the

halogenated polyether polyols or the

309882/1342

Mixtures of non-halogenated and new, halogenated Polyether polyols and organic polyisocyanates in the presence of a propellant and a reaction catalyst or several reaction catalysts, optionally of Water, emulsifiers and / or stabilizers, fillers, pigments, etc. are produced.

The new, halogenated polyether polyols are used in the production of polyurethane foams according to all the classic ones Procedures suitable for foaming, e.g. B. the one-step process or so-called "one-shot" process, the procedures, who use a prepolymer or a semi-prepolymer, the pre-expansion process or so-called "whipped foams" .

All commonly used to make rigid polyurethane foams Organic isocyanates used are suitable. Particularly preferred isocyanates are methylene bis (4-phenyl isocyanate) in the pure state or partially polymerized, tolyl isocyanates in the pure state or in the form of the isomers Mixtures or 1,5-naphthalene diisocyanate.

The theoretically required amount of polyisocyanate for production of the polyurethane is in a manner known per se as a function of the hydroxylindex of the polyether polyol or polyether polyols and, if applicable, the amount of water available. Advantageously, a light polyisocyanate - Excess applied to an isocyanate index of 105 to 120 ensure, whereby the heat deformation of the resulting rigid polyurethane foam is improved.

The catalyst used can be any of the known catalysts used for this purpose, in particular tertiary amines such as triethylenediamine (1,4-diazabicyclo-.2.2 } octane), triethylamine, trimethylamine, dimethylaminoethanol

309882/1342

and metal salts such as the salts of antimony, tin and iron. Triethylamine is a particularly preferred catalyst represent.

The amount of catalyst can vary to some extent; it affects the mechanical properties of the resulting material Foam. In general, 0.1 to 3% by weight is used Catalyst based on the polyether polyol or the mixture of polyether polyols.

The choice of propellant is not critical. The known propellants are all suitable and in particular, without exception Water, halogenated hydrocarbons such as methylene chloride and chloroform and the chlorofluoroalkanes, e.g. B. trichloromonofluoromethane (R 11), dichlorodifluoromethane (R 12) and trichlorotrifluoroethane (R 113).

The propellants'.ne.3g3 can also be used to a fairly large extent vary. It is advantageous to use 0.1 to 10% by weight of water and / or 1 to 70% by weight of halogenated hydrocarbons, based on "the polyether polyol or the mixture of polyether polyols.

The polyurethane foams can advantageously be produced by using small amounts of a surfactant that helps improve cell structure; 0.2 to 2% by weight, based on the polyether polyol or the mixture of polyether polyols, are preferably used .

The new, 'chlorinated polyether polyols can by oligomerization, cooligomerization, condensation, hydrogen chloride cleavage and hydrolysis from epichlorohydrin on the one hand and from water or di- or polyhydroxy compounds on the other hand, which are optionally halogenated and / or

309882/1342

Ether oxide bonds and / or at a later stage of the Have double bonds accessible to halogenation, can be prepared by working techniques known per se.

An advantageous way of working consists in the hydrolysis of Di- or polyglycidyl ethers of oligomers of epichlorohydrin of the following general formula are diluted in a medium Acid:

0 H-

-CH ₀ - CH - 0- 1 CH ₀ - CH CH 1 W. ■ CHpC. 0

O-CH-CH ₂ -CH ₂ Cl

where ζ denotes a number between 2 and 6, χ and y denote numbers between 0 and 12, the mean value χ + y per chain being between 0 and 12 and ζ (.x + l) ■> where χ + y is the mean value of χ + y in the entire molecule is between 1 and 72 and Z is a saturated or unsaturated organic, optionally halogenated'kest with the valence ζ.

This hydrolysis can be accompanied by secondary condensation reactions be which to a. Chain extension with the formation of chlorinated polyether polyols, which are richer in chlorine and are less rich in hydroxy! functions.

It is not absolutely necessary to separate these products, which are also chlorinated polyether polyols, the alpha-diol groups. contain. The presence of this affects the synthesis of further processed products in general not.

The hydrolysis of di- and polyglycidyl ethers of oligomers of epichlorohydrin is advantageously carried out in nitric acids or

309882/1342

perchloric acid medium.

The quantities of water and water to be used for the hydrolysis Acid can vary widely. They "determine in particular the duration of the reaction as well as the extent of secondary reactions of condensation. It is advantageous to use

—2 —2

1.2.10 to 2.5.10 moles of nitric acid and 1 to 10 kg of water per mole of di- or polyglycidyl ether.

The hydrolysis reaction takes place with stirring at the boiling point of the reaction mixture. The end of the reaction is determined by analyzing the residual oxirane oxygen. After cooling, the reaction product can be converted into a two-phase system are present, the aqueous phase containing the lightest polyether polyols, which is the richest of hydroxyl functions are, and the organic, dense, water-saturated Phase contains the heaviest polyether polyols, which are the most halogen-rich. It is it is not absolutely necessary to separate these two phases and separate them to isolate the polyether polyols they contain to treat.

The procedure described above is for the production of halogenated Polyether polyols "made to measure", which have relatively variable contents of halogen and hydroxyl groups, which by the choice of the suitable initial glycidyl ether and / or the hydrolysis conditions can be determined., suitable.

The di- and polyglycidyl ethers of oligomers of epichlorohydrin are known in a manner by splitting off hydrogen chloride in an alkaline medium from chlorinated polyether polyols obtained with terminal chlorohydrin residues, which originate from the oligomerization of epichlorohydrin, which by water or an aliphatic, alicyclic or aromatic, saturated or unsaturated, halogenated or non-halogenated di- or Polyhydrojcylverbindungen was initiated.

309882/1342

A first kind of di- and polyglycidyl ethers accordingly of the formula given above includes those compounds in which the radical Z in the formula is not halogenated. you will be obtained by elimination of hydrogen chloride from chlorinated polyether polyols, which result from catalytic oligomerization originate from epichlorohydrin, which is caused by saturated or unsaturated polyols such as ethylene, propylene and hexamethylene glycols, Glycerine, butane and hexanetriol, trimethylolpropane, Erythritol and pentaerythritol, mannitol and sorbitol, resorcinol, Catechin, hydroquinone, bisphenol A, di- and triethylene glycol, Di- or tripropylene glycol, 2-butene-1,4-diol, 3-butene-1,2-diol, 2-butyne-1,4-diol, 3-butyne-1,2-diol, 1,5-hexadiene-3,4-diol, 2,4-hexadiene-1,6-diol, Ί, 5-hexadiene-3,4-diol, 2,4-hexadiene-1,6-diol, was initiated. . ·

Particularly preferred polyols are the aliphatic polyols and in particular 2-butene-1,4-diol and 2-butyne-1,4-diol, ethylene glycol and glycerol. The use of these last-mentioned initiators leads to the production of di- and polyglycidyl ethers which correspond to the formula given above and in which Z denotes the radicals -CH ₀ -CH ₀ - or -CH ₀ -CH-CH ₀ -.

CCC I C.

A second type of di- and polyglycidyl ethers, which lead to polyether polyols with an increased halogen content are those in which the radical Z in the formula given above is halogenated where the halogen is chlorine or bromine. You can by splitting off hydrogen chloride from chlorinated polyether polyols obtained, which originate from the catalytic oligomerization of epichlorohydrin, the saturated or unsaturated, halogenated polyols such as monochlorohydrins and monobromohydrins Glycerine, 3,4-dibromo-1,2-butanediol, 2,3-dibromo-1,4-butanediol, 2,3-dibromo-2-butene-1,4-diols, 3,4-dibromo-2-butene-1,2-diols, 2,2 (bis) bromomethyl-1,3-propanediol, 1,2,5,6-tetrabromo-3,4-hexanediol, was initiated.

309882 / 13A2

_ 10 _

The oligomerization of epichlorohydrin can also be carried out by a mixture of brominated and / or unsaturated diols can be initiated.

The molar ratio of epichlorohydrin and polyol initiator is not critical and can vary within large amounts. This ratio determines the hydroxyl index of the resulting polyether polyol.

The oligomerization catalyst can be any of the known acidic catalysts for this type of reaction. Preferred however, boron trifluoride is used in free or complexed form State.

Di- and polyglycidyl ethers of brominated oligomers of epichlorohydrin can also be achieved by partial or total molecular bromination of di- or polyglycidyl ethers of unsaturated oligomers of the epichlorohydrin are obtained, which are split off by hydrogen chloride in an alkaline medium from unsaturated, chlorinated ones Polyether polyols were obtained, which from the catalytic oligomerization of epichlorohydrin, initiated by a unsaturated di- or polyhydroxyl compounds originate.

In addition, the halogen content of the new polyether polyols can be increased and thereby the flame resistance the polyurethanes derived from them are increased if these polyether polyols still have unsaturations, in that a partial or total bromination of these unsaturations takes place. This is the technique used to brominate them unsaturated polyols, which result from hydrolysis in a medium of dilute acid of di- or polyglycidyl ethers of unsaturated Oligomers of epichlorohydrin of the following general formula arise:

O - CH --CH ₀ -

-CH-O-CH ₂ Cl

-CH- CH. *

309882/1342

where χ, y and ζ correspond to the definition given above and ΐ an unsaturated, organic radical of the valence ζ represents.

The type of bromination of polyether polyols and glycidyl ethers is not critical. It is possible to work in a manner known per se, if appropriate in the presence of a catalyst and a catalyst inert solvents such as chloroform, carbon tetrachloride, methylene chloride or o ~ dichlorobenzene.

The temperature is maintained generally below 50 to 60 ⁰ C. ■.

The amount of bromine used is not critical. However, bromine is preferably used in a quasi-stoichiometric amount. The particularly preferred polyether polyols correspond to general formula in which Z represents the following radicals:

CH ₂ Cl-CH-; -CH ₂ -CHBr-CHBr-CH ₂ -; '

The invention is illustrated in more detail by means of the following examples. Examples 1, 2 and J relate to the preparation of mixtures of chlorinated polyether polyols Hydration of glycidyl ethers of oligomers of epichlorohydrin, which by adding epichlorohydrin to monochloropropanediol (Example 1),. . Ethylene glycol (Example 2) and Glycerin (Example '3) were obtained.

Example 4- relates to the preparation of chlorobrominated Polyether polyols by bromination of unsaturated, chlorinated polyether polyols, which result from the hydrolysis of diglycidyl ether originate from the addition of epichlorohydrin to butynediol was produced.

Examples 5 and 6 relate to polyurethane foams, which with the aid of mixtures of chlorinated polyether polyols prepared according to Examples 1 and 2 respectively.

309882/1342

Example 7 relates to polyurethane foams, which have been prepared using a mixture chlorobrominated polyether according Beipsiel 4 and a commercially available, non-halogenated polyether polyol which had a hydroxyl index of 503, a viscosity at 20 ⁰ C of 118 P and under the trade designation VOEANOL EN 490 in Trading is.

Example 8 is a comparative example and relates to polyurethane foams, which were produced with the help of a commercially available polyether polyol.

Example 9 is also a comparative example and relates to Polyurethane foams which are chlorinated with the aid of a according to French patent 1,350,425 and by oligomerization Polyether polyol synthesized from epichlorohydrin in the presence of glycerine in a molar ratio of 4/1.

Example 1 ■

In a 2 l glass reaction vessel, which was immersed in a thermostated oil bath and equipped with a stirrer and a reflux condenser was equipped, at ambient temperature 500 g,

d. H. 1 mole, diglycidyl ether of the tetramer of epichiorhydrin, 1000 ml of demineralized water and 12.5 ml of η nitric acid were introduced.

The mixture is brought to the boil and stirred continuously. After 20 hours the analysis of the oxirane oxygen indicates that the whole diglycidyl ether is hydrated. The reaction mixture is then cooled and as it is without separating the aqueous and organic phases an evaporation under reduced Subjected to pressure so that the greater part of the water is driven off. The chlorinated polyether polyols are then by azeotropic distillation of the water by means of

309882/1342

Dried methylene chloride. Taking it away with nitrogen at 60 ^° C. enables the last traces of water and methylene chloride to be driven off. A clear, relatively viscous liquid is obtained with the following properties:

specific gravity, 20 ⁰ C 1.337

Viscosity at 20 ⁰ C, P '750

Chlorine content, wt% 25

Hydroxylindex, mg EOH / g. Polyol 409 Gardner discoloration index 9

mean molecular weight, measured 534 mean from Tx ~ + y7, calculated. 1 »51

309882/1342

Example 2

The procedure of Example 1 is repeated using 500 g, i.e. H. 1.10 moles, of the diglycidyl ether of an oligomer of Epichlorohydrin can be used, which is produced by splitting off hydrogen chloride be made from the product that englykol from the addition of 5 moles of epichlorohydrin to 1 mole of ethyl came from.

A clear liquid is obtained with the following properties:

specific gravity, 20 ⁰ C 1.312

Viscosity at 20 ^° C., P 291 chlorine content, weight # 22.8

Hydroxylindex, mg KOH / g polyol 430 Gardner discoloration index 6

average molecular weight, measured 506 Mean of Tx + y), calculated 1.63

Example 3

The procedure of Example 1 is repeated, with 500 g, Ah. 0.55 mol of the triglycidyl ether of an oligomer of epichlorohydrin can be used, which is split off by hydrogen chloride was made from the product resulting from the addition of 10 moles of epichlorohydrin to 1 mole of glycerol. A very viscous liquid is obtained with the following properties:

specific gravity, 20 ⁰ C 1.34-3

Chlorine content, wt% 26.5

Hydroxylindex, mg KOH / g polyol 308 Gardner discoloration index '12

mean molecular weight, measured 989 mean value of Cx + J) ? calculated 2.59

309882/1342

Example 4

In a 2 1 reaction vessel made of glass, which is in a thermostated immersed in an oil bath and equipped with a stirrer and a reflux condenser, 500 g, d. H. 1,16MoI, the diglycidyl ether of an unsaturated oligomer of epichlorohydrin, which is produced by elimination of hydrogen chloride made from the product derived from the addition of 4.5 moles of epichlorohydrin to 1 mole of butynediol - 1000 ml demineralized water and 2.9 ml of an aqueous 70 wt .-% Perchloric acid solution added.

The procedure of Example 1 is then repeated. It. a mobile, brownish liquid is obtained, which 1.16 moles of chlorinated polyether polyol, which has acetylene-like unsaturation, correspond.

1.16 mol of bromine are added dropwise to the cooled reaction mixture, to which 1.4 g of boron trifluoride diethyl etherate have been added. It is ensured that the temperature does not exceed 50 ⁰ C. After the introduction of the bromine, which takes about two hours, the mixture is stirred further until the brown vapors of the gas phase have disappeared. The acid content is then neutralized by adding anhydrous calcium carbonate and held for two hours with vigorous stirring. A release of carbon dioxide is observed. 0.5 l of methylene chloride are added to the rather viscous mass obtained and then filtered to separate off the calcium carbonate. The methylene chloride is then ^{removed by evaporation at 95 0} C below 15 now mercury to constant weight.

The properties of the chlorinated polyether polyol obtained, which contains a double bond are the following:

specific weight, 20 ^° C. 1.67

Viscosity at 20 ^° C., P 900

Chlorine content, wt% 14.2

Bromine content, Gev /, -% 25j6

30 9 8 8 2/1342

* Hydroxylindex, mg KOH / g polyol 330

Gardner discoloration index 10

average molecular weight, measured 746 Mean of (χ + y), calculated 1> 9

Example 5

100 g of the chlorinated polyether polyols of Example 1, 0.5 S silicone DC 193 _? 2 6 triethylamine and 40 g trichlorofluoromethane (R 11) were introduced. The mixture is stirred so that it becomes completely homogeneous. 103 ₅ 8 S of crude methylene bis (4-phenyl isocyanate) are then added. The resulting mixture is stirred for 20 seconds, then poured into a mold and allowed to harden at ambient temperature. The creaming time is 3 seconds, the development time is 30 seconds. A rigid, self-extinguishing foam is obtained, the main physical and mechanical properties of which are determined. of Table I and the refractory properties of Table II.

Example 6

The procedure of Example 5 is repeated, with however, 100 g of the chlorinated polyether polyols of Example 4 and 109.2 g of crude methylene bis (4-phenyl isocyanate) were used will. The creaming time is 6 seconds and the development time 24 seconds. You get a rigid, self-extinguishing one Foam, the main physical and mechanical properties of which are given in Table I and the fire-resistant properties from Table II.

Example 7

The procedure is analogous to that in Example 5, however, 50 g of a mixture of the chlorobrominated polyether polyols of Example 6, 50 g of commercially available polyether polyol, 1.5 g triethylamine and 106 g methylene bis (4-phenyl isocyanate)

309882/1342

be used. In this way, a rigid, self-extinguishing foam is developed with a creaming time of 13 seconds and a development time of 75 seconds.

The main physical and mechanical properties of this foam are shown in Table I and its refractory properties from Table II.

Example 8 (comparative example)

The procedure is analogous to that described in Example 5, except that 100 g of commercially available polyether polyol, 128 g of methylene bis (4-phenyl isocyanate) and a mixture of amines, which 1.5 g of triethylamine and 0.5 g of triethylenediamine contains, can be used. In this way, a rigid, flammable foam is developed with a creaming time of 35 seconds and a development time of 85 seconds. The main ones Physical and mechanical properties of this foam are shown in Table I, its fire-resistant properties from table II .--

309882/1342

Table I. example

8 (cf.

Properties of the foam

seemingly specific

Weight, kg / m * 36.3 36

mean dimensions of cells, mm

in the horizontal direction '0.24 in the vertical direction 0.42

Proportion of closed cells (Scholten method),% ■ *)

Water absorption (ASTM standard

D 2127),% by volume 1.8

specific thermal conductivity (standard DIN 5 2612), cäl / cm. Be-C ⁰ C. 0.7-10 "

Compressive strength (ISO standard

R844), kg / cm ² **) IT

Tension at 10 Siger Deformation 1.64

maximum load 1.91

Flexural strength (ISO standard

R 1209) **)

Tear load, kg 1.56

Messex 'movement at

Tear, mm 18.1

Dimensional stability.

100 C and ambient humidity

Aluminum film method from ICI, specimen 15 x 15 x 1 cm, surface change, % after 1 day +5.8

after 7 days + 8.6

according to the Scholten method,

Specimen of 5x5x5 cm,

Change in the middle

Length of the flapping fin,%

after 1 day +0.53

after 7 days +1.1

Friability (ASTM standard

C 421)

Weight loss in%

after 2 minutes 4.0

after 10 minutes 16.8

29.6

0
0 , 22
, 46 0
0 , 32
, 46 0
O , 30
, 65 91 91 88 1 ,8th. 2 , 5 1 , 5 6th 10 '^ 0 , 63- 10 ~ ⁴ O, 6th 10 "

η 4 * n Φ> 1.88
1.88 1.35
1.35 1.93
ng 1.34
ng 2.37
ng ng
ng 1.49 φ>
2.66 η. S- η -G. 14.4 12.0 η. S- n.g.

0 O

ng
+ 0.5

2.0
11.2

n.g. + 4.5

n.g. n.g.

0.7 5.2

+ 4.7 + 8.3

4.2 26.0

309882/1342

not measured

does not include correction for the surface cells

Signs for stresses parallel to the expansion of the show

Sign for stresses perpendicular to the expansion of the foam

Table II

example 5 6th 7th 8 (comp.) Flammability test ASTh D 1692 standard; Great s.e. s.e. s.e. flammable elapsed before going out
Time, see 47 4-5 ■ 47 Burn time, see - - - 46 - Burn extent, cm 2.6 5.5 5 12.7 Burn extent,% 20.5 25.9 25.5 100 Burn rate,
cm / min 5.5 4.6 5.8 16.6 Flammability investigation CNorm AO ¹ JIl E 162) • Great s.e. s.e. s.e. flammable elapsed before the extinction
Time, see 152 n.g. 86 Burn time, see - n.g. - - Burn extent, cm 17.6 n.g. 51.5 - Burn extent,% 61.5 n.g. 90 _

Burn rate, cm / min

9.8

n.g.

n.g. s.e.

not measured self-extinguishing

30988 2/1342

Example 9 (comparative example)

The procedure is analogous to that described in Example 5, except that 100 g of an oligomer of epichlorohydrin are used are used, which by adding 5 moles of epichlorohydrin to 1 mole of glycerine. The main characteristics of this product are as follows:

specific gravity, 20 ⁰ C 1.34-7

Viscosity at 20 ^° C., P. 232

Chlorine content, wt%. 32.41

Hydroxylindex, mg KOH / g polyol 282

Gardner discoloration index. 3 mean molecular weight, measured 548

In addition to the 100 g of the oligomer described above, 0.5 g of silicone DC 193, 1.5 g of triethylamine, 30 g of trichlorofluoromethane are used and 71-6 g of crude methylene bis (4-phenyl isocyanate) are used.

The creaming time increases to 20 seconds.

After 101 seconds a foam with a specific Weight of 35.8 kg / irr designed according to the standards ASTM D 1692 and E 162 is self-extinguishing.

The flexural strength and compressive strength properties of this foam are comparable to those of the foam produced according to Example 5. However, its dimensional stability is completely insufficient; the changes in the surface or the mean length of the flippers of test specimens of 15 × 15 × 1 cm, which were kept for one day at 100 ^° C. under ambient humidity, are not measurable at all because of the softening of the test specimens and the occurrence of numerous cracks.

The comparison of properties of rigid, according to the examples 5j shows 6, 7ϊ 8 and 9 produced polyurethane foams

309882/1 342

clearly that the new, chlorinated polyether polyols

enable the production of rigid, self-extinguishing foams with mechanical properties, those more rigid, with the help of non-halogenated ones Polyether polyols produced foams are comparable or superior, and in particular have good dimensional stability have, a property which is indispensable for the effective use of rigid foams and which under use previously known, chlorinated polyether polyols do not have foams produced.

- patent claims -

309882/1342

Claims (10)

Claims Process for the production of iron by polyurethane foams Reaction of an organic polyisocyanate with at least one polyether polyol in the presence of a conventional catalyst and a conventional blowing agent, characterized in that a halogenated polyether polyol is used is used, which corresponds to the following general formula: O - CH - CH ^ + - O CH ₂ Cl -CH-O CH ₂ Cl CH ₀ - CH - CH ₀ OH OH where ζ is a number between 2 'and 6, χ and y are numbers mean between 0 and 12, the mean value χ + y pro Chain is between 0 and 12 and ζ (χ + y), where χ + y the mean value of χ + y in the entire molecule is between 1 and 72, and Z is an organic radical with the valence ζ represents. 2. The method according to claim 1, characterized in that a halogenated polyether polyol is used in which Z is the divalent, organic radical CH ₂ Cl-CH- / -ITT _ means. 2 3. The method according to claim 1, characterized gekennz eichn et that a halogenated polyether polyol is used, wherein Z is the saturated, non-halogenated, divalent radical -CH ₂ -CH ₂ -. 4-. Process according to Claim 1, characterized in that a halogenated polyether polyol is used, in which Z is the saturated, non-halogenated, trivalent organic radical -CH ₀ -CH-CH ₀ -. 309882/1342 5. "Method according to claim 1, characterized in that it is marked e t that a halogenated polyether polyol is used in which Z has an organic, unsaturated radical the valence ζ means. 6. The method according to claim 1, characterized in that that a halogenated polyether polyol is used, in which Z is a brominated, saturated or unsaturated, organic residue with the valence ζ "means. 7. The method according to claim 6, characterized gekennz eichn et that a halogenated polyether polyol is used, wherein Z is the saturated, brominated divalent, organic radical -CH ₀ -CH-CH-CH ₀ -. C- II C. ' Br Br 8. The method according to claim 6, characterized in that a halogenated polyether polyol is used, in which Z is the unsaturated, brominated, divalent, organic radical -CH ₀ -C = C-CH ₀ -. C- \ ι C. BrBr 9 · Method according to one of the preceding claims, characterized gekennz eichnet that one-halogenated polyether polyol of the formula given in claim 1, wherein χ and y are numbers between 0 and 4 ·, where the Mean value x + J per chain is between 0 and 4- and ζ (χ + y), where χ + y means the mean value of χ + y in the entire molecule, is between 1 and 24. 10. Semi-rigid or rigid polyurethane foams made by the method according to one of claims 1 to 9 309882/1342