JPH02147642A - Phenolic resin foam composition - Google Patents

Abstract

PURPOSE:To provide the title foam composition having a uniform and fine cell structure and a high closed cell rate by foaming and curing a phenolic resin in the presence of a specified surfactant and an acid curing agent by using a low-boiling organic blowing agent. CONSTITUTION:A phenolic resin (A) is mixed with a surfactant (B) containing at least one diglycerol or polyglycerol ricinolate/alkylene oxide adduct (B), an acid curing agent (C) (e.g. phenolsulfonic acid) and a low-boiling organic blowing agent (e.g. fluorotrichloromethane). This mixture is poured into a container and heated to foam and cure into a phenolic resin foam composition. The obtained foam composition can be desirably used as a heat-insulation material, because it has a uniform and fine cell structure and a high closed cell rate, and therefore has excellent heat insulation properties and excellent burning resistance and weathering resistance, etc., and it is lowly smoking.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a phenolic resin foam composition, and particularly to a phenolic resin foam composition having a more uniform cell structure, finer cells, and a higher closed cell ratio than conventional ones.

Phenolic resin foam has traditionally had excellent heat resistance, flame resistance, low smoke emission, cold resistance, and weather resistance, and in recent years its flame resistance and low smoke emission have been highly praised, and attempts have been made to use it as a heat insulating material. It is being

However, compared to existing insulation materials such as polystyrene foam and rigid urethane foam, phenolic resin foam has disadvantages such as brittle foam, slightly inferior insulation properties, and corrosion resistance of metals. When used as an insulating material, the thermal insulation properties have not yet been achieved.

The cell structure is largely responsible for the inferior insulation properties of phenolic resin foams compared to other insulation materials.

In other words, the cell structure of the phenolic resin foam has a lack of closed cells and is mainly formed of open cells, resulting in poor heat insulation properties, which we believe can be solved by increasing the closed cell ratio.

The method for producing phenolic resin foam is to mix an acidic curing agent, an organic blowing agent, a foam stabilizer, etc. with a resol type resin initial condensate.
It is foamed at room temperature or under heating.

At this time, the component that greatly affects the structure of the foam is the surfactant used as a foam stabilizer, and conventionally, polyoxyethylene nonylphenyl ether, polyoxyethylene lauryl ether, polyoxyethylene sorbitan stearate, castor oil ethylene oxide addition body, nonionic activators such as polyoxyethylene dimethyl silicone alone or in combination, and anions such as dodecylbenzenesulfonate Na salt, dioctyl sulfosuccinate Na salt, lauryl sulfate Na salt, and polyoxyethylene nonylphenyl ether sulfate Na salt. Although surfactants have been used in combination with the above-mentioned nonionic surfactants, it has not yet been possible to obtain a closed cell ratio to provide satisfactory heat insulation properties.

The present inventors have conducted extensive studies to solve these problems, and as a result, have arrived at the present invention.

That is, the present invention provides a phenolic resin foam composition obtained using a low boiling point organic blowing agent in the presence of a surfactant and an acidic curing agent, in which ricinoleic acid of diglycerin or polyglycerin is used as the surfactant. The present invention provides a phenolic resin foam composition containing at least one ester alkylene oxide adduct.

Diglycerin and polyglycerin, which are the constituent components of the surfactant of the present invention, can be used either as a dehydrated clamp of glycerin or as a polymer of glycidol.

Polyglycerin includes triglycerin, tetraglycerin,
Examples include decaglycerin.

The esterification rate of ricinoleic acid to the hydroxyl groups of diglycerin or polyglycerin is sufficient as long as one or more esters exist in one molecule, but preferably 40 to 100 of the total hydroxyl groups in one molecule of diglycerin or polyglycerin.
% esterification rate is good.

Examples of the alkylene oxide include ethylene oxide, propylene oxide, butylene oxide, etc., which are subjected to addition polymerization using known synthesis methods to produce individual adducts of each alkylene oxide, block adducts of two or more types, or random additions of two or more types of alkylene oxides. I can list things.

The amount of alkylene oxide added is 20 to 80% of the total molecular weight,
Preferably it is 30-70%.

The amount of the surfactant of the present invention used is 0.1 to 10 parts by weight per 100 parts by weight of the resol type phenolic resin initial condensate;
Preferably it is 0.65 to 5 parts by weight.

If the amount exceeds 10 parts by weight, the foam will have a fine closed-cell structure, but mechanical strength, heat resistance, and water resistance will deteriorate, which is not preferable. If the amount of O is less than 1 part by weight, a foam having a uniform fine cell structure of closed cells cannot be obtained.

Furthermore, the surfactant of the present invention can also be used in combination with at least one other conventionally used surfactant.

Next, examples of acidic curing agents that can be used in the present invention include hydrochloric acid,
Inorganic acids such as sulfuric acid and phosphoric acid, and monochloroacetic acid.

p-) Luenesulfonic acid, benzenesulfonic acid.

Percussion acids such as β-naphthalenesulfonic acid and phenolsulfonic acid, all of which can act as strong acids, are preferred, and one or more of these acids may be used in combination.

In addition, organic blowing agents include volatile petroleum compounds such as petroleum ether, naphtha, pentane, and hexane, low molecular weight fatty acid esters such as ethyl acetate, ketones such as methyl ethyl ketone and acetone, and lower aliphatic compounds such as methyl alcohol and ethyl alcohol. -hydric alcohols, as well as methylene chloride, carbon tetrachloride, trichloroethane, and dichloromethylene.

Examples include low boiling point halogenated hydrocarbons such as fluorotrichloromethane and trifluorotrichloroethane.

The resol type phenolic resin initial condensate used in the present invention is produced by reacting phenols and aldehydes in equimolar ratios or in excess of aldehydes in the presence of an alkaline catalyst.

Examples of phenols include phenol, cresol, ethylphenol, and propylphenol, and examples of aldehydes that react with phenols include formaldehyde, acetaldehyde, and the like.

In addition, alkaline catalysts include magnesium hydroxide, calcium hydroxide, barium hydroxide, sodium hydroxide,
Examples include potassium hydroxide, ammonium hydroxide, hexamethylenetetramine, and the like.

The surfactant of the present invention is a high molecular weight surfactant having a polymorphic structure. Therefore, the compatibility with the resol type phenol resin initial condensate is extremely good, and the emulsifying and dispersing power of the organic blowing agent, acidic curing agent, etc. in the resol type phenol resin initial condensate is extremely excellent. . Therefore, since the cells during foaming are fine and uniform, the foaming pressure generated within the cells is relatively small, so the cell membrane does not break and a phenolic resin foam with a high closed cell ratio can be obtained. .

Further, it is also possible to add, for example, an organic or inorganic fibrous substance, a plasticizer such as ethylene glycol or tung oil, or a flame retardant such as trischloroethyl phosphate to the phenolic resin foam composition of the present invention.

The present invention will be explained in detail below with reference to Examples.

Examples 1-10. Comparative Examples 1 to 5 Phenol 1.0 mol Formaldehyde (37% aqueous solution) 2.0 mol Caustic soda 3% by weight relative to phenol Reaction was carried out according to a conventional method at the above blending ratio, and after the reaction was completed, the caustic soda was neutralized using lactic acid. and adjust the system to pH 6-7. Next, the water content is 1
Dehydration was performed until the concentration became 5% by weight to obtain a resol type phenol resin. This is called resin A.

100 parts by weight of resin A, 4.0 parts by weight of the surfactant shown in the table as a foam stabilizer, 2 Freon 113 as a foaming agent.
Add 20.0 parts by weight and mix with high speed stirring. After that, 20% of phenolsulfonic acid (purity 63%) was used as a curing catalyst.
．． 0 parts by weight added, 3000-5000 r, p, m
After stirring and mixing at high speed for 20 to 40 seconds, the mixture was immediately poured into a container and foamed and hardened at 50 to 80°C. The performance results are shown in Table 2.

As shown in the table, the obtained foam had a uniform cell structure and a high closed cell ratio.

Examples 11 to 13 For 100 parts by weight of resin A used in Examples 1 to 10,
The surfactant (B) used in Example 2 as a foam stabilizer was
．． A similar foam was obtained by using 5 to 8.0 parts by weight and keeping all other conditions the same.

Table 3 shows the results when the amount of foam stabilizer added was varied.

(Margin below)

Claims (1)

[Claims] In the phenolic resin foam composition obtained using a low boiling point organic blowing agent in the presence of a surfactant and an acidic curing agent, a ricinoleic acid ester alkylene oxide adduct of diglycerin or polyglycerin is used as the surfactant. A phenolic resin foam composition containing at least one type.