JP2007070503A - Phenol resin-foamed article - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a phenol resin-foamed article having a fine cellular structure with many closed cells and the flexibility of the cell walls, and as a result, excellent in flame retardant/fire-preventing property, inhibiting the cracks, etc., of the cell walls, especially having a low initial heat conductivity and excellent in heat insulation performance. <P>SOLUTION: This phenol resin-foamed article is obtained by foaming/curing a foamable phenol resin-molding material containing a phenol resin, blowing agent, foam stabilizer and curing agent, wherein the blowing agent contains a 2-5C chlorinated aliphatic hydrocarbon compound and the foam stabilizer contains a castor oil ethylene oxide adduct obtained by adding >20 mol and <40 mol ethylene oxide based on 1 mol castor oil. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention has a phenol resin foam, more specifically, a fine cell structure with many closed cells and the flexibility of the cell walls. As a result, it has excellent flame resistance and fire resistance, and cracks in the cell walls are suppressed. In particular, the present invention relates to a phenol resin foam having a low initial thermal conductivity and excellent heat insulating performance.

Conventionally, a phenol resin foam is excellent in heat insulation, flame retardancy, fire resistance, and the like, and thus has been used as a heat insulating material in construction and other industrial fields.
By the way, in order to improve the heat insulation performance of the phenol resin foam, it is important that the bubbles in the phenol resin foam have a fine and closed cell structure. For this reason, the phenol resin raw material is produced during the production of the phenol resin foam. It has been proposed to mix a foam stabilizer (bubble stabilizer).

  As a foam stabilizer, a method for producing a phenol resin foam using castor oil ethylene oxide (hereinafter referred to as “EO”) adduct has been reported. For example, 2 to 20 mol of EO is added to 1 mol of castor oil. The castor oil EO adduct (see Patent Document 1) and the castor oil EO adduct (see Patent Document 2) obtained by adding 40 to 90 mol of EO to 1 mol of castor oil have been reported.

However, it has become clear that the castor oil EO adducts disclosed in Patent Documents 1 and 2 have the following problems according to the study by the present inventors.
(1) When the castor oil EO adduct having 2 to 20 mol of EO added as disclosed in Patent Document 1 is used as a foam stabilizer, the heat insulation performance of the resulting phenol resin foam is low. Moreover, since the heat insulation performance of the obtained phenol resin foam varies greatly due to slight fluctuations in the number of moles of EO added in the castor oil EO adduct, it is possible to stably obtain a phenol resin foam having a predetermined heat insulation performance. I can't. Moreover, the moisture permeability coefficient of the obtained phenol resin foam is also high.
(2) Castor oil EO adducts disclosed in Patent Document 2 having an added mole number of EO of 40 to 90 moles have a higher number of added moles of EO, which not only increases the production cost, Although the number of added moles of EO is increased, the heat insulation performance of the obtained phenol resin foam is low, and the moisture permeability coefficient is also high.

  On the other hand, a phenol resin foam having an independent cell structure is known to have a heat insulation performance with good stability over time. As a method for producing a phenol resin foam having an independent cell structure, a physical material containing chloropropane is used. A method using a static foaming means has been proposed (see, for example, Patent Document 3).

JP-A-61-268733 JP 63-39933 A Japanese Patent Publication No. 5-87093

  Under such circumstances, the present invention has the fine cell structure with many closed cells and the flexibility of the bubble wall, and as a result, has excellent flame retardancy and fire resistance and suppresses cracks in the bubble wall. In particular, an object of the present invention is to provide a phenol resin foam having a low initial thermal conductivity and excellent heat insulating performance.

  As a result of intensive research to develop a phenol resin foam having the above-mentioned preferable properties, the present inventors have found that a chlorinated aliphatic hydrocarbon compound having a specific number of carbon atoms, preferably chloropropane, as a foaming agent. It is found that the object can be achieved by using a castor oil EO adduct having an EO addition mole number in a specific range as a foam stabilizer, and the present invention is based on this finding. It came to be completed.

That is, the present invention
(1) A foam obtained by foam-curing a foamable phenol resin molding material containing a phenol resin, a foaming agent, a foam stabilizer, and a curing agent, wherein the foaming agent has 2 to 5 carbon atoms. A phenolic resin foam comprising a hydrocarbon compound and the foam stabilizer comprising a castor oil ethylene oxide adduct obtained by adding more than 20 moles and less than 40 moles of ethylene oxide to 1 mole of castor oil ,
(2) The phenol resin foam as described in (1) above, wherein the chlorinated aliphatic hydrocarbon compound having 2 to 5 carbon atoms is chloropropanes,
(3) The phenolic resin foam according to (1) or (2) above, wherein the foamable phenolic resin molding material contains 1 to 20 parts by weight of a foaming agent per 100 parts by weight of phenolic resin,
(4) The phenolic resin foam according to any one of (1) to (3) above, wherein the foamable phenolic resin molding material contains 1 to 5 parts by weight of castor oil ethylene oxide adduct per 100 parts by weight of phenolic resin body,
(5) The phenolic resin foam according to any one of (1) to (4) above, wherein the foamable phenolic resin molding material further contains urea,
(6) The phenolic resin foam according to any one of (1) to (5) above, wherein the foamable phenolic resin molding material further contains an inorganic filler,
(7) The thermal conductivity is 0.022 W / m · K or less, and the moisture permeability is 60 ng / m ² · s · Pa or less, according to any one of the above items (1) to (6) Phenolic resin foam,
(8) The phenol resin foam according to any one of (1) to (7) above, wherein the closed cell ratio is 85% or more and the oxygen index is 29 or more,
(9) The phenol resin foam according to any one of (1) to (8) above, wherein a face material is provided on at least one surface, and (10) the face material is a glass fiber nonwoven fabric or a span. The phenol resin foam described in (9) above, which is at least one selected from a bond nonwoven fabric, an aluminum foil-clad nonwoven fabric, a metal plate, a metal foil, a plywood, a calcium silicate plate, a gypsum board, and a wood cement board ,
Is to provide.

  According to the present invention, a foaming agent containing a chlorinated aliphatic hydrocarbon compound having 2 to 5 carbon atoms is used, and a castor oil EO adduct having an EO addition mole number within a specific range is used as a foam stabilizer. It has a fine cell structure with a lot of closed cells and the flexibility of the cell walls.As a result, it has excellent flame resistance and fire resistance, and cracks of the cell walls are suppressed. A phenol resin foam excellent in performance can be provided.

  The phenol resin foam of the present invention is obtained by foam-curing a foamable phenol resin molding material containing a phenol resin, a foaming agent, a foam stabilizer, a curing agent, and, if desired, urea and / or an inorganic filler and a plasticizer. It is.

  The phenolic resin comprises phenols such as phenol, cresol, xylenol, paraalkylphenol, paraphenylphenol, resorcin, and modified products thereof, and aldehydes such as formaldehyde, paraformaldehyde, furfural, acetaldehyde, sodium hydroxide, potassium hydroxide, water. A resol type phenol resin obtained by adding a catalytic amount of alkali such as calcium oxide, trimethylamine, triethylamine, and the like is preferable, but is not limited thereto. The ratio of the phenols and aldehydes to be used is not particularly limited, but is usually about 1: 1.5 to 1: 3.0, preferably 1: 1.8 to 1: 2.5 in molar ratio.

In the present invention, as the foaming agent, one containing a chlorinated aliphatic hydrocarbon compound having 2 to 5 carbon atoms is used. The chlorinated aliphatic hydrocarbon compound having 2 to 5 carbon atoms is a chlorinated product of linear or branched aliphatic hydrocarbon having 2 to 5 carbon atoms, and the number of bonds of chlorine atoms is not particularly limited. However, about 1-4 are preferable. Examples of such chlorinated aliphatic hydrocarbon compounds include dichloroethane, propyl chloride, isopropyl chloride, butyl chloride, isobutyl chloride, pentyl chloride, isopentyl chloride, and the like. These may be used alone or in combination of two or more. Among these, chloropropanes such as propyl chloride and isopropyl chloride are preferable, and isopropyl chloride is particularly preferable.
By using such a chlorinated aliphatic hydrocarbon compound as a foaming agent, the obtained foam has a low initial thermal conductivity.

  The foaming agent used in the present invention is characterized by containing a chlorinated aliphatic hydrocarbon compound. However, as long as the performance and physical properties of the phenol resin foam of the present invention are not impaired, for example, 1,1, Fluorinated hydrocarbon compounds such as 1,3,3-pentafluorobutane (alternative chlorofluorocarbons), salt fluorinated hydrocarbon compounds such as trichloromonofluoromethane and trichlorotrifluoroethane, hydrocarbons such as butane, pentane, hexane and heptane It is possible to add an appropriate amount and an appropriate amount of a system compound, an ether compound such as isopropyl ether, a gas such as nitrogen, argon or carbon dioxide, air or the like. The amount is preferably 0.1 to 20%, more preferably 0.5 to 15%, based on the chlorinated aliphatic hydrocarbon compound.

In this invention, the usage-amount of the said foaming agent is 1-20 weight part normally with respect to 100 weight part of above-mentioned phenol resins, Preferably it is 5-10 weight part.
In the present invention, as the foam stabilizer, one containing castor oil EO adduct is used.
Castor oil is a non-drying oil obtained by pressing from seeds such as castor sesame, and mainly contains unsaturated acids such as ricinoleic acid, oleic acid and linoleic acid, and small amounts of saturated acids such as stearic acid and dioxystearic acid. Is included.

In the said foam stabilizer, EO is added more than 20 mol and less than 40 mol with respect to 1 mol of said castor oil.
The reason why the number of moles of EO added is limited to more than 20 moles and less than 40 moles is that, as described above, when the number of moles of EO added is more than 20 moles and less than 40 moles, the long chain hydrocarbon group of castor oil is mainly used. And a hydrophilic group mainly composed of a polyoxyethylene group formed by EO of more than 20 mol and less than 40 mol are arranged in a balanced manner in the molecule, and a good surface activity can be obtained. By using a castor oil EO adduct having such a good surface activity, the bubble diameter of the phenol resin foam can be kept small, and flexibility can be given to the bubble wall, resulting in the occurrence of cracks in the bubble wall. This is because an effect such as prevention is obtained. The added mole number of EO is preferably 21 to 38 moles.

  In the present invention, the castor oil EO adduct is used as an essential component as a foam stabilizer, but in addition to this, dimethylpolysiloxane-polyoxyalkylene copolymer, dimethylpolysiloxane-polyoxyethylene-polyoxypropylene copolymer A coalescence, a castor oil propylene oxide adduct, etc. can also be used.

  Further, the content of the castor oil EO adduct in the foamable phenol resin molding material is preferably 1 to 5 parts by weight, more preferably 2 to 4 parts by weight, per 100 parts by weight of the phenol resin. When the content of the castor oil EO adduct is less than 1 part by weight, the bubbles are difficult to be uniformly reduced. On the other hand, when the content exceeds 5 parts by weight, the water absorption of the produced phenolic resin foam is increased and the production cost is increased. Becomes higher.

  In the present invention, examples of the curing agent include acid curing agents such as inorganic acids such as sulfuric acid and phosphoric acid, benzenesulfonic acid, paratoluenesulfonic acid, xylenesulfonic acid, ethylbenzenesulfonic acid, naphtholsulfonic acid, and phenolsulfonic acid. These organic acids are used. One of these curing agents may be used alone, or two or more thereof may be used in combination.

In the present invention, the urea used as desired can provide a phenol resin foam having a low initial thermal conductivity and a strength, particularly a low brittleness.
Phenolic resins are obtained by the dehydration condensation reaction between phenols and formaldehyde, but when urea is present at the same time, most of them do not have urea residues in the molecule, but when urea-resin-containing phenol resins are produced in part. It is considered. That is, NH ₂ CONH ₂ reacts with a part of HCHO to produce various methylol ureas (for example, HOCH ₂ NHCONH ₂ , HOCH ₂ NHCONHCH ₂ OH, etc.), and the methylol residues react with phenols or phenol resins. to, for example, _{Ph-CH 2 NHCONH 2, Ph-} (CH 2 NHCONH 2) 2, Ph-CH 2 NH 2 CONHCH 2 OH, Ph- (CH 2 NHCONHCH 2 OH) 2, HOCH 2 NHCONHCH 2 -Ph-CH ₂ NHCONHCH ₂ OH, and these dehydration condensates are also produced together with the phenolic resin. Ph represents a phenol residue or a phenol resin. This improves the mechanical strength, in particular the brittleness, of the phenolic resin and thus the phenolic foam. That is, the brittleness is improved (the numerical value becomes smaller. Unit:%) The amount of urea used is usually 1 to 10 parts by weight, preferably 3 to 7 parts by weight with respect to 100 parts by weight of the phenol resin.

  Moreover, the inorganic filler used as desired can provide a phenol resin foam having low thermal conductivity and acidity and improved fire resistance. The amount of the inorganic filler used is usually 0.1 to 30 parts by weight, preferably 1 to 10 parts by weight with respect to 100 parts by weight of the above-mentioned phenol resin.

  Examples of the inorganic filler include metal hydroxides and oxides such as aluminum hydroxide, magnesium hydroxide, calcium oxide, magnesium oxide, aluminum oxide, and zinc oxide, metal powder such as zinc, calcium carbonate, magnesium carbonate, and carbonate. Metal carbonates such as barium and zinc carbonate can be contained. These inorganic fillers may be used alone or in combination of two or more.

In the present invention, a plasticizer is optionally used for the following reasons.
It has been confirmed that the thermal conductivity of a plastic heat insulating material such as a phenol resin foam changes over time from the time of manufacture. This is due to the diffusion of the gas in the bubble to the outside of the system, and is a phenomenon in which the foaming agent permeates the bubble film and is gradually replaced with air in the atmosphere. Therefore, the phenol resin foam also has a phenomenon in which its thermal conductivity increases with time and the heat insulation performance deteriorates with time.

  As one of the causes of the deterioration of the phenol resin foam over time, a phenomenon in which the flexibility of the cell walls of the phenol resin foam deteriorates with time can be considered. Therefore, as one of means for suppressing deterioration of the phenol resin foam, it is possible to give flexibility to the cell walls. The addition of the plasticizer is performed in order to impart flexibility to the cell walls of the foam and to suppress deterioration over time of the heat insulation performance.

  The plasticizer is not particularly limited, and known plasticizers conventionally used in phenol resin foams such as triphenyl phosphate, dimethyl terephthalate, dimethyl isophthalate, and the like can be used. Furthermore, a polyester polyol can also be used.

  In particular, the polyester polyol has a structure including an ester bond and a hydroxyl group that are hydrophilic and excellent in surface activity, and thus has a good compatibility with the hydrophilic phenol resin liquid and can be uniformly mixed with the phenol resin. . Moreover, by using this polyester polyol, it is a preferable plasticizer that avoids uneven distribution of bubbles, distributes the bubbles uniformly throughout the foam, and easily produces a phenol resin foam that is homogeneous in quality.

  The polyester polyol is obtained by reacting a polyvalent carboxylic acid and a polyhydric alcohol, and there is no particular limitation on the molecular weight, but from the viewpoint of performance that imparts flexibility to the cell wall and suppresses deterioration over time. The weight average molecular weight is preferably about 200 to 10,000, and more preferably 200 to 5,000. Moreover, it is preferable from the point of the said performance to have at least two hydroxyl groups in one molecule. The number of carboxyl groups in one molecule of the polyvalent carboxylic acid is not particularly limited as long as it is 2 or more. Further, the number of hydroxyl groups in one molecule of the polyhydric alcohol is not particularly limited as long as it is 2 or more.

The polyester polyol can be obtained as a reaction product of, for example, a divalent to tetravalent polycarboxylic acid and a divalent to pentavalent polyhydric alcohol.
Preferred examples of the divalent to tetravalent polyvalent carboxylic acid include aromatic dicarboxylic acids, aliphatic dicarboxylic acids, and alicyclic dicarboxylic acids. Here, examples of the aromatic dicarboxylic acid include phthalic acid, isophthalic acid, terephthalic acid, naphthalene-2,3-dicarboxylic acid, naphthalene-1,4-dicarboxylic acid, and naphthalene-2,6-dicarboxylic acid. The aliphatic dicarboxylic acid is preferably a saturated aliphatic dicarboxylic acid from the viewpoint of the stability of the resulting polyester polyol, and examples thereof include adipic acid, pimelic acid, suberic acid, azelaic acid, and sebacic acid. . The alicyclic dicarboxylic acid is preferably a saturated alicyclic dicarboxylic acid from the viewpoint of the stability of the resulting polyester polyol. Cyclohexane-1,2-dicarboxylic acid, cyclohexane-1,3-dicarboxylic acid, cyclohexane- Examples include 1,4-dicarboxylic acid.

  On the other hand, a dihydric alcohol is preferable as the divalent to pentavalent polyhydric alcohol, and examples of the dihydric alcohol include aromatic glycol, aliphatic glycol, and alicyclic glycol. The formula glycol is preferred.

  Examples of aromatic glycols include benzenedimethanol groups such as benzene-1,2-dimethanol, benzene-1,3-dimethanol, and benzene-1,4-dimethanol; catechol, resorcinol, hydroquinone, 2,2-bis Examples thereof include ethylene oxide or propylene oxide adducts such as (4-hydroxyphenyl) propane (bisphenol A). Examples of the aliphatic glycol include ethylene glycol, propylene glycol, 1,3-propanediol, 1,2-butanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 1, Alkanediols such as 8-octanediol and 1,9-nonanediol; oxyalkylene glycols such as diethylene glycol, triethylene glycol, polyethylene glycol, dipropylene glycol, tripropylene glycol, and polypropylene glycol; β-butyrolactone, γ-butyrolactone , Polyester diols which are ring-opening products of lactones such as δ-valerolactone and oxyalkylene glycols such as ethylene glycol, diethylene glycol and triethylene glycol, -Dimethyl-1,3-propanediol (Nenpentyl glycol), 2,2-diethyl-1,3-propanediol, 2,2-dipropyl-1,3-propanediol, 2,2-diisopropyl-1,3 -Propanediol, 2,2-dibutyl-1,3-propanediol, 2,2-diisobutyl-1,3-propanediol, 2-methyl-2-dodecyl-1,3-propanediol, 2-butyl-2 Examples thereof include hindered glycols such as ethyl-1,3-propanediol and 2-propyl-2-pentyl-1,3-propanediol.

  As the alicyclic glycol, cyclopentane-1,2-diol, cyclopentane-1,2-dimethanol, cyclohexane-1,2-diol, cyclohexane-1,2-dimethanol, cyclohexane-1,3 Examples include diol, cyclohexane-1,3-dimethanol, cyclohensan-1,4-diol, cyclohexane-1,4-dimethanol, 2,5-norbornanediol, and the like.

  In the present invention, aliphatic glycols and alicyclic glycols are preferable as the dihydric alcohol, and in particular, ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol, 1,4-butanediol, 1,6-hexanediol, neopentyl. Glycol, cyclohexane-1,2-dimethanol, cyclohexane-1,3-dimethanol and cyclohexanedimethanol are preferred.

  The polyester polyol is, for example, 1.2 mol or more, preferably 1.2 to 5 mol, more preferably 1.5 to 5 mol of the dihydric alcohol with respect to 1 mol of the divalent carboxylic acid. It can be produced by carrying out an esterification reaction at a temperature of usually about 100 to 320 ° C., preferably 150 to 300 ° C., preferably in the presence of a known esterification catalyst.

  In the present invention, the plasticizer is usually used in the range of 0.1 to 20 parts by weight with respect to 100 parts by weight of the phenol resin. When the amount of the plasticizer used is in the above range, the effect of imparting flexibility to the cell wall is satisfactorily exhibited without impairing other performances of the obtained phenol resin foam. The preferred amount of the plasticizer is 0.5 to 15 parts by weight, more preferably 1 to 12 parts by weight.

  In the present invention, the foamable phenol resin molding material is mixed, for example, with the above-mentioned phenol resin by adding the foam stabilizer containing the castor oil EO adduct, and, if necessary, the urea and / or inorganic filler and plasticizer. And after adding the foaming agent and hardening | curing agent containing the said chlorinated aliphatic hydrocarbon compound to this mixture, it can prepare by supplying this to a mixer and stirring.

  As a method of forming a phenol resin foam using the foamable phenol resin molding material thus prepared, for example, (1) a molding method for flowing out onto an endless conveyor, (2) a portion that is caused to flow out in a spot manner (3) a method of foaming under pressure in a mold, (4) a method of making a foam block by putting it in a large space, (5) a method of filling and foaming while press-fitting into a cavity, etc. Can be mentioned.

  As a preferable method, the foamable phenol resin molding material is discharged onto a continuously moving carrier, and the discharged material is foamed through a heating zone and molded to produce a desired phenol resin foam. To do. Specifically, the foamable phenol resin molding material is discharged onto a face material on a conveyor belt. Next, a face material is placed on the upper surface of the molding material on the conveyor belt and enters a curing furnace. In the curing furnace, the material is pressed from above with another conveyor belt, the phenolic resin foam is adjusted to a predetermined thickness, and foamed and cured under conditions of about 60 to 100 ° C. for about 2 to 15 minutes. The phenol resin foam exiting the curing furnace is cut into a predetermined length.

  The face material is not particularly limited, and is generally a natural fiber, a synthetic fiber such as polyester fiber or polyethylene fiber, a non-woven fabric such as inorganic fiber such as glass fiber, paper, an aluminum foil-clad nonwoven fabric, a metal plate, a metal Foil is used, but glass fiber nonwoven fabric, spunbond nonwoven fabric, aluminum foil tension nonwoven fabric, metal plate, metal foil, plywood, structural panel, particle board, hard board, wood cement board, flexible board, perlite board, silica Calcium oxide board, magnesium carbonate board, pulp cement board, shizing board, medium density fiber board, gypsum board, lath sheet, volcanic glass composite board, natural stone, brick, tile, glass molding, lightweight cellular concrete molding, cement Mortar molded products, glass fiber reinforced cement molded products, etc. Molded body curable cement hydrate as a binder component are preferred. This face material may be provided on one side of the phenol resin foam or may be provided on both sides. Moreover, when providing in both surfaces, a face material may be the same and may differ. In addition, a face material may be attached later using an adhesive.

  In the phenol resin foam of this invention, it is preferable that heat conductivity is 0.022 W / m * K or less, More preferably, heat conductivity is 0.020 W / m * K or less. When this thermal conductivity exceeds 0.022 W / m · K, the heat insulating performance of the phenol resin foam becomes insufficient.

The brittleness is preferably 30% or less, more preferably 20% or less.
Further, the density is about 10 to 100 kg / m ³ , the average cell diameter is about 5 to 400 μm, and the void area ratio in the cross-sectional area of the foam is preferably 5% or less. Furthermore, the pores are substantially free of pores, the closed cell ratio is usually 85% or more, preferably 90% or more, and the area ratio of the pyrolysis product trimethylphenol (A) to phenol (B) ( C) (where C = A / B) is preferably in the range of 0.05 to 4.0. The oxygen index is preferably 29 or more, more preferably 30 or more. Further, the moisture permeability coefficient per 25 mm thickness is usually 60 ng / (m ² · s · Pa) or less, preferably 55 ng / (m ² · s · Pa) or less.

The method for measuring the property of the phenol resin foam will be described in detail later.
In the phenol resin foam of the present invention, since the cell walls are given flexibility, deterioration over time is suppressed, and stable heat insulation performance can be maintained over a long period of time.

EXAMPLES Next, although an Example demonstrates this invention further in detail, this invention is not limited at all by these examples.
In addition, the physical property of the phenol resin foam obtained in each example was measured according to the method shown below.

(1) Density Measured according to JIS A 9511: 2003, 5.6 density.
(2) Thermal conductivity Using a 300 mm square phenolic resin foam sample, set to a low temperature plate of 10 ° C. and a high temperature plate of 30 ° C., and according to the heat flow meter method of JIS A 1412-2: 1999, the thermal conductivity measuring device HC- 074 304 (manufactured by Eiko Seiki Co., Ltd.) was used for measurement. The initial thermal conductivity is the thermal conductivity after leaving the phenolic resin foam sample in a 70 ° C. atmosphere for 4 days.
(3) Brittleness Measured according to JIS A 9511: 2003, 5.14 Brittle (brittle) test.
(4) pH
Weigh 0.5 g of a phenol resin foam sample micronized to 250 μm (60 mesh) or less with a mortar or the like into a 200 ml conical stoppered flask, add 100 ml of pure water, and seal tightly. The mixture was stirred at room temperature (23 ± 5 ° C.) for 7 days using a magnetic stirrer and then measured with a pH meter.
(5) Average cell diameter Four straight lines with a length of 9 cm are drawn on a 50 times magnified photograph inside the phenol resin foam sample, and the number of bubbles crossed by each line is obtained by each line, and the average value (JIS) 1800 μm divided by the number of cells measured according to K6402.
(6) Void A substantially central portion in the thickness direction of the phenol resin foam sample was cut parallel to the front and back surfaces, and a 100 mm × 150 mm range was enlarged 200% (each length was doubled, that is, the area was quadrupled). ) Was taken and the area of the void was calculated by integrating the void area of 1 mm × 1 mm square with 8 squares or more using a transparent graph paper. That is, since an enlarged copy is taken, these 8 squares correspond to an area of 2 mm ^{2 in} an actual foam cross section.

(7) Area ratio of trimethylphenol to phenol A pyrogram of pyrolysis gas chromatography is measured as follows.
The phenol resin foam sample is further carefully pulverized with a mortar from the powder cut out from the core portion with a cutter knife, and the sample amount is 0.3 to 0.4 mg per measurement. As the thermal decomposition apparatus, PY2010D manufactured by Frontier Lab, which is a heating furnace type thermal decomposition apparatus, is used. The thermal decomposition temperature is 670 ° C. Measurement by gas chromatography is Hewlett-Packard HP5890A type and uses a nonpolar liquid phase capillary column (Durabondo) DB-1 (inner diameter 0.25 mm, film thickness 0.25 μm, length 30 m). The carrier gas is helium (He), the total flow rate is 100 cm ³ / min, the head pressure is 100 kPa, the oven temperature is started from 50 ° C., the temperature is increased to 340 ° C. at a speed of 20 ° C. per minute, and held for 15.5 minutes.
Each component is detected by a flame ionization detector (FID), and the area value of each peak is normalized by all the detected components to obtain the ratio of each component. However, in the case where the skirts of the peaks overlap, a perpendicular line is dropped from the valley where the peaks overlap to the base line, and the range surrounded by the base line and the perpendicular is defined as the peak area.
The structure of each component is confirmed by a mass spectrum obtained by introducing components separated by gas chromatography into a mass spectrometer. The mass spectrum is measured by JEOL JMS AX-505H by an electron impact ionization method (EI method) at an ionization voltage of 70 eV and an ionization current of 300 mA.
The area ratio (C) (C = A / B) of trimethylphenol (A) to phenol (B) is calculated from the pyrogram.

(8) Moisture permeability coefficient per 25 mm thickness ISO 1663: 1999 Rigid foamed plastic-Measured according to the method for determining water vapor permeability. In addition, the calcium chloride used as the hygroscopic agent was about 2.5 to 3.5 mm in diameter.
(9) Oxygen index JIS K7201-2 Plastics-Test method for flammability by oxygen index-Part 2: Measured by tests at room temperature.
(10) Closed cell ratio Measured by ASTM D2856.

Production Example 1 Production of Castor Oil EO Adduct After 932 g (1 mol) of castor oil and 5.9 g of potassium hydroxide as a catalyst were charged into a stainless steel 2 L autoclave equipped with stirring and temperature control, the system was replaced with nitrogen. , 968 g (22 mol) of EO was introduced and reacted at 140 to 160 ° C. to a gauge pressure of 1 to 4 kgf / cm ² . After aging reaction for 1 hour at the above temperature, the catalyst (potassium hydroxide) is adsorbed with an adsorbent KYOWARD 600 (manufactured by Kyowa Chemical Industry Co., Ltd.), and dehydrated at 120 ° C. for 1 hour (about 20 mmHg). By filtration and purification, a 22 mol castor oil EO adduct was obtained.

Example 1
100 parts by weight of a resol-type phenol resin [trade name “PF-333” manufactured by Asahi Organic Chemicals Co., Ltd.] obtained by reacting phenol and formaldehyde in a molar ratio of 1: 2 and internally containing 5 parts by weight of urea 3 parts by weight of castor oil EO adduct (added mole number 22) as a foam stabilizer was added and mixed.
5 parts by weight of calcium carbonate as an inorganic filler is added to 103 parts by weight of this phenol resin mixture, 8 parts by weight of isopropyl chloride as a foaming agent, and a weight ratio of paratoluenesulfonic acid: xylenesulfonic acid as a curing agent = 2: 1. 15 parts by weight was supplied to a pin mixer, stirred and mixed to prepare a foamable phenolic resin molding material. Subsequently, this molding material was discharged into a mold frame laid with a glass nonwoven fabric, put into a dryer at 80 ° C., and foamed for 10 minutes to be molded to obtain a phenol resin foam. The physical properties of this foam are shown in Table 1.

Example 2
A phenol resin foam was obtained in the same manner as in Example 1, except that the foaming agent in Example 1 was changed to a mixture of isopropyl chloride: HFC-245fa (hydrofluorocarbon produced by Asahi Allied Signal) = 80: 20. Obtained. The physical properties of this foam are shown in Table 1.

Example 3
A phenol resin foam was obtained in the same manner as in Example 1 except that the foaming agent in Example 1 was changed to a mixture of isopropyl chloride: nitrogen weight ratio = 98: 2. The physical properties of this foam are shown in Table 1.

Example 4
A phenol resin foam was obtained in the same manner as in Example 1 except that the foaming agent in Example 1 was changed to a mixture of isopropyl chloride: nitrogen: isopentane weight ratio = 98: 1.5: 0.5. The physical properties of this foam are shown in Table 1.

Example 5
In Example 1, a phenol resin foam was obtained in the same manner as in Example 1 except that urea was not added to the resol type phenol resin. The physical properties of this foam are shown in Table 1.

Example 6
In Example 1, a phenol resin foam was obtained in the same manner as in Example 1 except that calcium carbonate was not added to the resol type phenol resin. The physical properties of this foam are shown in Table 1.

Comparative Example 1
A phenol resin foam was obtained in the same manner as in Example 1 except that the foaming agent in Example 1 was changed to a mixture of dichloromethane: HFC-245fa (hydrofluorocarbon manufactured by Asahi Allied Signal) = 80: 20. It was. The physical properties of this foam are shown in Table 1.

Comparative Example 2
A phenol resin foam was obtained in the same manner as in Example 1 except that the foam stabilizer (castor oil EO 22 mol adduct) in Example 1 was changed to castor oil EO 18 mol adduct. The physical properties of this foam are shown in Table 1.

  The phenol resin foam of the present invention includes a foam resin containing a chlorinated aliphatic hydrocarbon compound and a foam stabilizer containing a castor oil EO adduct having a specific number of EO addition moles. It has a fine cell structure with a lot of closed cells and the flexibility of the cell walls. As a result, it has excellent flame resistance and fire resistance, and cracks of the cell walls are suppressed. The phenolic resin foam of the present invention which is excellent in use is suitably used as a heat insulating material in construction and other industrial fields.

Claims (10)

  A foam obtained by foam-curing a foamable phenol resin molding material containing a phenol resin, a foaming agent, a foam stabilizer, and a curing agent, wherein the foaming agent is a chlorinated aliphatic hydrocarbon compound having 2 to 5 carbon atoms. And the foam stabilizer comprises a castor oil ethylene oxide adduct formed by adding more than 20 moles and less than 40 moles of ethylene oxide to 1 mole of castor oil.   The phenol resin foam according to claim 1, wherein the chlorinated aliphatic hydrocarbon compound having 2 to 5 carbon atoms is chloropropanes.   The phenol resin foam according to claim 1 or 2, wherein the foamable phenol resin molding material contains 1 to 20 parts by weight of a foaming agent per 100 parts by weight of the phenol resin.   The phenol resin foam according to any one of claims 1 to 3, wherein the foamable phenol resin molding material contains 1 to 5 parts by weight of castor oil ethylene oxide adduct per 100 parts by weight of the phenol resin.   The phenol resin foam according to any one of claims 1 to 4, wherein the foamable phenol resin molding material further contains urea.   The phenol resin foam according to any one of claims 1 to 5, wherein the foamable phenol resin molding material further contains an inorganic filler. The phenol resin foam according to any one of claims 1 to 6, having a thermal conductivity of 0.022 W / m · K or less and a moisture permeability coefficient of 60 ng / m ² · s · Pa or less.   The phenol resin foam according to any one of claims 1 to 7, wherein the closed cell ratio is 85% or more and the oxygen index is 29 or more.   The phenol resin foam according to any one of claims 1 to 8, wherein a face material is provided on at least one surface.   The face material is at least one selected from a glass fiber nonwoven fabric, a spunbond nonwoven fabric, an aluminum foil-clad nonwoven fabric, a metal plate, a metal foil, a plywood, a calcium silicate plate, a gypsum board, and a wood cement board. The phenolic resin foam described in 1.