JP2551481B2 - Foaming phenolic resin composition - Google Patents

Description

TECHNICAL FIELD The present invention relates to a phenol resin composition for foaming, which is useful for producing an acid-curable phenol resin foam mainly used as a fireproof heat insulating material for structures.

[Conventional technology]

In recent years, phenolic resin foams have attracted attention as fire-resistant heat insulating materials in applications such as building materials and general industrial materials because of their low smoke emission, almost no generation of harmful gases, and excellent flame resistance and heat resistance. Was.

However, as is well known, the phenolic resin foam has a disadvantage that the wall film forming the bubbles is fragile and easily broken, so that the foaming agent is dissipated from the bubbles at the time of or after the production of the foam and the heat insulation performance is reduced. Have.

Therefore, the present inventors have previously proposed a phenol resin foam obtained by foaming and curing a liquid phenol resin, an acidic curing agent, a foaming agent, a manufacturing agent, and a compounded composition containing a saccharide as an essential component. -238833 publication).

[Problems to be solved by the invention]

The phenol resin foam described in the above-mentioned JP-A-61-238833 is superior in fragility resistance (fly aviability), heat insulation and its temporal stability (normal temperature) as compared with conventional phenol resin foams. However, as a result of further detailed study, it was found that when the foam is left in an environment where the temperature changes drastically, the heat insulating performance is deteriorated, and there is a problem that the application is greatly restricted.

Therefore, an object of the present invention is to retain the characteristics of the phenol resin foam described in JP-A-61-238833 and to have a small influence of environmental temperature on the heat insulation performance, which is suitable for the production of a phenol resin foam. To provide a phenolic resin composition.

[Means for solving problems]

As a result of studies to improve the above-mentioned drawbacks, the present inventors have found that the intended purpose can be achieved by using a partial or complete acetylated product of a specific castor oil ethylene oxide adduct as a foam stabilizer. Heading out, the present invention has been completed.

That is, the foaming phenol resin composition of the present invention,
Resol type liquid phenol resin, acidic curing agent, foaming agent,
In a phenolic resin composition for foaming containing a saccharide and a foam stabilizer as essential components, an acetylation treatment of a castor oil ethylene oxide adduct obtained by adding 20 to 70 mol of ethylene oxide per 1 mol of castor oil as a foam stabilizer. And a partially or completely acetylated castor oil ethylene oxide adduct having a hydroxyl value of 15 mgKOH / g or less.

The resol type liquid phenol resin used in the present invention contains a phenol resin and an aldehyde in the presence of a catalyst, for example, in a proportion of 0.8 mol or more, preferably 1 to 4 mol of aldehyde relative to 1 mol of the phenol resin. It can be prepared by an addition condensation reaction, and preferably by further neutralizing and concentrating.

As the phenol resin, usually, in addition to phenol, cresol, xylenol, nonylphenol,
Alkylphenols such as p-t-butylphenol, polyhydric phenols such as resorcinol, catechol and pyrogallol, bisphenols such as bisphenol A and bisphenol F, cresol residues, resorcinol residues, catechol residues, and phenolic purification residues such as bisphenol A residues Etc. are used. On the other hand, as aldehydes, in addition to formaldehyde-supplying substances such as formalin, paraformaldehyde and acetal, formaldehyde synergistic substances such as glyoxal and furfural are used. The phenols and aldehydes are not limited to the above-exemplified products, and two or more of them may be used in combination.

Further, as the catalyst, sodium hydroxide, potassium hydroxide, lithium hydroxide, sodium phosphate, potassium carbonate, sodium hydrogen carbonate, hydroxide barium, hydroxide calcium, calcium oxide, ammonia, hexamethylenetetramine, triethylamine, An alkaline catalyst such as triethanolamine, an acidic divalent metal salt such as zinc borate, zinc acetate, lead acetate, lead naphthenate, zinc chloride and a mixture thereof are used.

Further, as the acids used for neutralizing the catalyst,
Examples thereof include hydrochloric acid, sulfuric acid, phosphoric acid, boric acid, oxalic acid, acetic acid, lactic acid, phenolsulfonic acid, paratoluenesulfonic acid, and mixtures thereof.

The foam stabilizer used in the present invention is a castor oil ethylene oxide adduct obtained by adding 20 to 70 mol (preferably 30 to 60 mol) of ethylene oxide per 1 mol of castor oil, and, for example, acetic anhydride, It is a partial or complete acetylated product of castor oil ethylene oxide adduct having a hydroxyl value of 15 mgKOH / g or less obtained by reacting with an acetylating agent such as acetyl chloride or glacial acetic acid. If either or both of the number of moles of ethylene oxide added or the hydroxyl value deviates from the above range, only a foam-stabilizing effect similar to that of conventional castor oil ethylene oxide adduct can be obtained, and the heat insulating performance aimed at by the present invention is obtained. It is not possible to obtain a foam that is less affected by the ambient temperature.

The amount of the foam stabilizer used is usually 0.1 to 10 relative to 100 parts by weight of the solid content of the resol type liquid phenolic resin.
Parts by weight, preferably 2-5 parts by weight. Usage is 0.1
If the amount is less than 10 parts by weight, the heat insulating performance cannot be improved. On the other hand, if the amount is more than 10 parts by weight, no further improvement in the heat insulating performance is observed, which is rather economically disadvantageous.

The acidic curing agent used in the present invention is not particularly limited, and paratoluene sulfonic acid, xylene sulfonic acid, metaxylene sulfonic acid, benzel sulfonic acid, phenol sulfonic acid, polymeric sulfone, which are commonly used in the art, are used. Examples thereof include acids, organic sulfonic acids such as styrene sulfonic acid, inorganic acids such as phosphoric acid and sulfuric acid, and mixtures thereof. Usually, the amount of the acidic curing agent used is 3 to 100 parts by weight based on 100 parts by weight of the solid content of the resol type liquid phenol resin.

The foaming agent used in the present invention is appropriately selected mainly depending on the required heat insulating performance, but usually it is a halogenated hydrocarbon such as methylene chloride, 1,2-dichloroethane, trichloroethane and tetrachloromethane. Chlorohydrocarbons, trichloromonofluoromethane, dichloromonofluoromethane, 1,1,2-trichlorotrifluoroethane, 1,2-dichlorotetrafluoroethane, 1,2-dichloro-1-fluoroethane, 1,1- Halogenated fluorocarbons such as dichloro-2,2,2-trifluoroethane and mixtures thereof are used. Of these, halogenated fluorocarbons that are advantageous in terms of heat insulation performance are particularly preferred. In addition, aliphatic hydrocarbons such as butane, pentane, and hexane, aliphatic ethers such as diethyl ether and diisopropyl ether, and chemical blowing agents such as sodium hydrogencarbonate may be used alone or in accordance with the purpose of use. It can also be used in combination with a kind. Usually, the amount of these foaming agents used is 100% solid content of the resol type liquid phenol resin.
It is 1 to 50 parts by weight with respect to parts by weight.

Examples of the saccharides used in the present invention include monosaccharides, disaccharides, trisaccharides, polysaccharides and mixtures thereof. Specifically, ribose, xylose, arabinose, glucose, mannose, galactose, fructose, maltose, lactose, saccharose, molasses, raffinose, gentianose, stachyose, carboxymethyl cellulose, starches such as potato starch, celluloses such as starch, potato starch. Examples thereof include gum arabic, fructan, and the like. Among them, sucrose, molasses, fructose, glucose, lactose, maltose, gum arabic and the like are particularly preferable. Usually, the amount of the saccharide used is 0.1 to 50 parts by weight based on 100 parts by weight of the solid content of the resol type liquid phenol resin.

Further, in addition to the above-mentioned components, various additives such as resorcinol and a curing accelerator such as alkylresorcinol may be added to the foaming phenolic resin composition, if necessary.
Formaldehyde scavengers such as urea and melamine, neutralizing agents such as zinc powder, melamine resins, phosphorus compounds, flame retardants such as halogen compounds, shirasu balloons, glass balloons, porous aggregates, wood powders, etc. Incorporating inorganic or organic fillers, ceramic fibers, glass fibers, carbon fibers, phenol fibers, aramid fibers, fiber reinforcements such as vinylon fibers, anticorrosion agents such as polyisocyanates, and other plasticizers, colorants, etc. You can

The preparation of the foaming phenolic resin composition of the present invention is a known resol type liquid phenolic resin, an acidic curing agent, a foaming agent, a foam stabilizer, a saccharide and various additives to be blended as necessary depending on the purpose of use. The foamable composition can be prepared by a method such as batch or continuous high speed stirring and mixing method, spray mixing method, and floss mixing method.

The foaming phenolic resin composition of the present invention thus obtained is made into a phenolic foam by various foaming methods depending on the purpose of use, such as continuous foaming method, mold foaming method, in-situ foaming method or impregnation foaming method, and the like. It is used as a fireproof heat insulating material for ceiling materials, inner wall materials, outer wall materials, floor base materials, shutters, automobile ceiling materials, electric refrigerators, showcases, tanks, transportation containers, piping, etc.

〔Example〕

Next, the present invention will be specifically described based on examples, but the present invention is not limited to these examples. In addition, "%" shown in Examples and Comparative Examples represents "% by weight" unless otherwise specified, and the measurement of characteristic values of resole resin and the evaluation of physical properties of foams thereof are as follows.

1. "Viscosity" was measured by a B-type viscometer, "pH" was measured by a pH meter, and "water" was measured by the Karl Fischer method.

2. "Number average molecular weight" was measured by gel permeation chromatography using a standard polystyrene calibration curve.

3. "Density" is JIS A 9514, "Thermal conductivity" is a TC-32 type thermal conductivity meter (Kyoto Denshi Kogyo Co., Ltd.) using a 70 × 100 × 30mm sample in an atmosphere of 22 ± 2 ° C. Hot wire method using
"Oxygen index" is JIS K 7201 and "flyability"
Were measured by ASTM C421, respectively.

4. "Heat cycle test" is 10 ℃ for 12 hours ~ 80 ℃
The thermal conductivity after repeating the thermal history 10 times for 12 hours as one cycle was measured by the hot wire method, and the decrease in thermal conductivity due to the temperature change was evaluated.

[Example 1] (Production of resol type liquid phenolic resin) 30 kg of phenol, 30.6 kg of 47% formalin and 1.35 kg of 20% aqueous potassium hydroxide solution were charged into a reaction kettle equipped with a reflux condenser, a thermometer and a stirrer and stirred. Raise the temperature down to about 100 ° C for 1
After the addition condensation reaction for 20 minutes, it was cooled to about 50 ° C. The viscosity of the obtained reaction product was 34 cp / 50 ° C. Then 4
The pH was adjusted to 5.8 using a 0% phenolsulfonic acid aqueous solution, and heated and concentrated under a vacuum of 600 mmHg to obtain a resol type liquid phenol resin (hereinafter referred to as resin A). The resin A thus obtained has a viscosity of 5100 cp / 25 ° C, a number average molecular weight of 275 and a water content of 11.8.
%, And the solid content was 78%.

(Production of Phenolic Resin Composition for Foaming and Foam) Next, 0.6 kg of sucrose in 10 kg of the above resin A, Pionine D-245A manufactured by Takemoto Yushi Co., Ltd. as a foam stabilizer (partial acetylation product of 45 mol ethylene oxide adduct of castor oil) Hydroxyl number 3 mgKOH / g) 0.3 kg were mixed and dissolved in solution I, and Freon 113 [a product name of Asahi Glass Co., Ltd., 1,1,2-
[Trichlorotrifluoroethane] as solution II and 65% phenolsulfonic acid aqueous solution as an acidic curing agent as solution III, and these are the weight ratio of solution I: solution II: solution III = 100: 16: 16 (weight ratio). Then, the foaming machine PA-21 for phenol foam
0 (trade name of Toho Machinery Co., Ltd.) was mixed to prepare a phenolic resin composition for foaming, which was quickly poured into a 70 ° C temperature control mold lined with kraft paper having a basis weight of 75 g / m ^2. , Lightly pressurize to foam and harden the foam (1800 mm ×
900 mm × 25 mm) was produced.

The obtained foam was measured for its physical properties after standing at 20 ° C. for 7 days and the thermal conductivity after standing at 20 ° C. for 30 days, respectively, by the above-mentioned test methods. Table 1 shows the results.

[Examples 2 to 4 and Comparative Examples 1 to 4] In Example 1, the same procedure as in Example 1 was carried out except that each foam stabilizer having a different ethylene oxide addition mole number or a different hydroxyl value was used. The thing and its foam were produced. The obtained foam was treated in the same manner as in Example 1, and its physical properties were measured by the test methods described above. Table 1 shows the results.

[Effects of the Invention] As described above, the foaming phenolic resin composition of the present invention retains excellent flame resistance, brittleness resistance and heat insulation performance described in JP-A-61-238833. In addition, it is possible to provide a phenol resin foam which is less affected by the change in environmental temperature on the heat insulation performance. It not only brings practical expansion, but is also extremely useful industrially as a highly reliable fireproof heat insulating material.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Akihiro Maruyama 1305-7-101 Nagatsuta-cho, Midori-ku, Yokohama-shi, Kanagawa (72) Inventor Ishiwaka 2-20-22, Minamimaioka-cho, Totsuka-ku, Yokohama-shi, Kanagawa 72) Inventor Takashi Ohashi 710-3-403 Kamiyabe-cho, Totsuka-ku, Yokohama-shi, Kanagawa Prefecture

Claims (1)

(57) [Claims] 1. A foaming phenolic resin composition containing a resol type liquid phenolic resin, an acidic curing agent, a foaming agent, a saccharide and a foam stabilizer as essential components, the foam stabilizer being 20 to 20 mol per 1 mol of castor oil. Castor oil with 70 moles of ethylene oxide added Hydroxyl number of 15 mg obtained by acetylating ethylene oxide adduct
A phenol resin composition for foaming, which comprises using a partially or completely acetylated castor oil ethylene oxide adduct having a KOH / g or less.