JPH05140416A - Thermosetting resin composition - Google Patents

Abstract

PURPOSE:To obtain the subject compsn. excellent in heat resistance by compounding a resolic phenol resin having blocked phenolic hydroxyl groups and a polyamine. CONSTITUTION:A resolic phenol resin having blocked phenolic hydroxyl groups (obtd. by substituting the hydrogen atoms of phenolic hydroxyl groups of a resolic phenol resin, which is obtd. by reacting a phenol with an aldehyde in the presence of a basic catalyst, with other groups such as alkyl groups) and a polyamine (e.g. m- or p-phenylenediamine) are compounded pref. in a wt. ratio of (1:2) to (5:1) to give the objective compsn., which is remarkably excellent in heat resistance and can be used in various applications where conventional phenol resins cannot be used because of insufficient heat resistance, such as for a molding material, a laminated board, a mold for metal casting, a resin felt, an adhesive, and a fiber-treating agent.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thermosetting resin composition, and more specifically, it has excellent thermosetting properties suitable for molding materials, laminates, mold materials, resin felts, adhesives, fiber treatment agents, etc. Moreover, the present invention relates to a thermosetting resin composition having excellent heat resistance.

[0002]

2. Description of the Related Art Thermosetting resins, such as those represented by amino resins and phenol resins, which use formaldehyde as a crosslinking agent, or unsaturated resins such as unsaturated polyester resins, allyl resins and bismaleimide resins. Although they are crosslinked through a saturated bond, there are epoxy resins and urethane resins which are crosslinked by polyaddition.

These thermosetting resins are used in various applications depending on their characteristics. Then, in various industries such as electric, electronic, automobile, construction, grindstone, and refractory materials, the purpose of further improving the heat resistance of these thermosetting resins so that the current thermosetting resins can be used at higher temperatures. Various improvements have been made in. However, a thermosetting resin that can sufficiently meet the recent demand for higher heat resistance has not been found yet.

[0004]

SUMMARY OF THE INVENTION An object of the present invention is to provide a thermosetting resin composition which overcomes the drawbacks of the prior art and has excellent heat resistance.

[0005]

Means for Solving the Problems As a result of various studies to solve the above-mentioned drawbacks of the prior art, the present inventors have found that a thermosetting resin containing a resol-type phenol resin in which a phenolic hydroxyl group is shielded and a polyamine. The inventors have found that a resin composition can solve the above problems, and have reached the present invention.

That is, the present invention relates to a thermosetting resin composition containing a resol type phenol resin having a phenolic hydroxyl group shielded and a polyamine.

The present invention will be described in more detail below. The resol type phenolic resin having a shielded phenolic hydroxyl group used in the present invention means a hydrogen atom of the phenolic hydroxyl group of the resol type phenolic resin obtained by reacting phenols and aldehydes in the presence of a basic catalyst. Substituted with another atomic group, for example, alkyl etherified, vinyl etherified, allyl etherified, butenyl etherified, propargyl etherified, styryl etherified, esterified and the like.

As used herein, the phenols may include all those having at least one phenolic hydroxyl group in the molecule. Phenol, if specifically exemplified,
Cresol, xylenol, tert-butylphenol, phenylphenol, nonylphenol, cumylphenol, isopropenylphenol, bromophenol, fluorophenol, aminophenol, resorcinol, catechol, isopropylcatechol, pyrogallol, glycinol, bisphenol A, bisphenol F, bisphenol S, Biphenol and the like can be mentioned, and these can be used alone or as a mixture of two or more kinds.

Examples of aldehydes include, but are not limited to, formalin, paraformaldehyde, trioxane, tetraoxane, acetal, glyoxal, acetaldehyde, butyraldehyde, benzaldehyde, acrolein and furfural.

As the basic catalyst, alkaline catalysts such as sodium hydroxide, sodium carbonate, oxides and hydroxides of alkaline earth metals, ammonia and hexamine are used.

The method for producing the resol type phenol resin is not particularly limited, and usually 1 to 4 mol of aldehydes and 40 to 10 mol of aldehydes in the presence of a basic catalyst with respect to 1 mol of phenols.
It can be obtained by reacting at 0 ° C. for 1 to 10 hours.

The resol type phenol resin in which the phenolic hydroxyl group is shielded is 0.5 to 2.0 moles of methyl halide, ethyl halide or halogenated with respect to 1.0 mole of the phenolic hydroxyl group of the resol type phenol resin. Alkyl halides such as propyl and butyl halide,
Vinyl halides, allyl halides, butenyl halides, propargyl halides, chloromethylstyrene, bromomethylstyrene, methyl iodide styrene, chloromethyl-α-methylstyrene, chloromethyl-α-ethylstyrene, etc. Acid chlorides such as halogenated styrenes, propanoyl chloride, butanoyl chloride, p-octadecenoyl chloride, monochloroacetic acid and the like are added to sodium hydroxide, barium hydroxide,
It can be obtained by reacting in the presence of a basic catalyst such as potassium hydroxide or calcium hydroxide to etherify or esterify the phenolic hydroxyl group.

In the resol type phenol resin in which the phenolic hydroxyl group is shielded, it is preferable that at least 50% or more of the phenolic hydroxyl group in the resol type phenol resin is shielded.

The polyamine used in the present invention includes
Meta or paraphenylenediamine, meta or paraxylenediamine, 1,4- or 1,3-cyclohexanediamine, hexaxylenediamine, 4,4-diaminobiphenyl, bis (4-aminophenyl) methane, bis (4-aminophenyl) ) Ether, bis (4-aminophenyl) sulfone, bis (4-amino-3-methylphenyl) methane, bis (4-amino-3,5-methylphenyl) methane, bis (4-aminophenyl) cyclohexane, 2 , 2-bis (4-aminophenyl) propane, 2,2-bis (4-amino-3-methylphenyl)
Propane, 2,2-bis (4-amino-3-chlorophenyl) propane, bis (4-amino-3-chlorophenyl) methane, 2,2-bis (4-amino-3,5-dibromophenyl) propane, bis (4-aminophenyl)
Examples thereof include phenylmethane, 3,4-diaminophenyl-4-aminophenylmethane, and 1,1-bis (4-aminophenyl) -1-phenylethane, which may be used alone or as a mixture of two or more kinds. Can be used.

The amount of polyamine used is preferably such that the weight ratio of the resol type phenolic resin in which the phenolic hydroxyl groups are shielded to the polyamine is 1: 2 to 5: 1.
If the amount of polyamine used is more than this range, the crosslink density will be low, heat resistance will not be improved, and the cost will be increased. On the other hand, if the amount of polyamine used is less than this range, the desired effect of improving heat resistance cannot be expected.

The mixing of the resol-type phenolic resin having a blocked phenolic hydroxyl group with the polyamine is preferably carried out in the presence of a solvent such as methanol, ethanol, acetone, methyl ethyl ketone, dioxane or dimethylformaldehyde. Further, these mixtures can be used as they are or after partially reacting. The partial reaction is carried out in the presence of a catalyst or without a catalyst of 20 to
It is carried out in a temperature range of 200 ° C., preferably 50 to
It is 150 ° C. If the temperature is lower than 20 ° C, the reaction takes a long time,
On the other hand, if the temperature exceeds 200 ° C, there is a risk that the reaction will proceed excessively and gelation may occur.

Needless to say, the thermosetting resin composition of the present invention may contain a modifier, a filler, a release agent, a colorant, a flame retardant, etc., if necessary.

As the modifier, epoxy resin, acrylic resin, methacrylic resin, silicone resin, acrylic resin
Epoxy resin, silicone-epoxy resin, alkyd resin, polyester resin, polyurethane resin, melamine resin, urea resin, xylene resin, phenol-modified xylene resin, polyimide resin, polybutadiene resin, polyvinyl butyral resin, polybutene resin, cyclopentadiene resin, diallyl phthalate Resins, rubber-like polymers, natural resins such as drying oil, thermoplastic resins and the like can be used.

The filler used is a fibrous filler such as polyvinyl alcohol fiber, polyamide fiber, wood powder, cellulose fiber such as pulp, polyester fiber, aramid fiber, carbon fiber, glass fiber, metal fiber and mineral fiber. Examples thereof include powder and plate-like inorganic fillers such as calcium carbonate, clay, silica, magnesium oxide, aluminum oxide, mica, wollastonite, and titanium. These fillers are used by blending 50 to 500 parts by weight with respect to 100 parts by weight of the resol-type phenol resin in which the phenolic hydroxyl group is shielded.

As the release agent, stearic acid, calcium stearate, zinc stearate, magnesium stearate, carnauba wax, molytanic acid ester, paraffin wax, polyethylene and the like can be preferably used.

[0021]

The details of why the thermosetting resin composition of the present invention is excellent in curability and heat resistance are not clear. However, a resol type phenol resin having a blocked phenolic hydroxyl group and a polyamine are used. When cross-linking is carried out, a new reaction occurs between the methylol group and the amino group.

[Chemical 1] It is presumed that heat resistance is improved by the bonding. Also,
It is presumed that the reduction of the phenolic hydroxyl group due to the shielding of the phenolic hydroxyl group also contributes to the improvement of the heat resistance.

[0022]

EXAMPLES The present invention will be described in more detail with reference to Examples and Comparative Examples.

Resol with a shielded phenolic hydroxyl group
Production of type phenolic resin A In a flask equipped with a stirrer, reflux condenser, thermometer,
1000 g of phenol and 2600 g of 37% formalin were added and uniformly dissolved. Then sodium hydroxide 47
The internal temperature of an aqueous solution prepared by dissolving 0 g in 470 g of water was 30 to 3
The mixture was gradually added while maintaining it at 5 ° C. The internal temperature was kept at 40 ° C. and the reaction was carried out for 6 hours and a half. After the reaction, the temperature was cooled to around room temperature.

191 g of allyl chloride was added to 1000 g of this reaction product, and the mixture was reacted at 40 ° C. for 6 hours. After the reaction, the mixture was allowed to stand and the aqueous layer was separated and removed. Then water 5
00 g was added, and the procedures of stirring, standing and separating the aqueous layer were repeated 4 times to carry out desalination purification. 315 g of allyl etherified resol type phenol resin was obtained (hereinafter referred to as resin A). The allyl etherification rate was 86% as measured by ¹ H-NMR.

Resol with a shielded phenolic hydroxyl group
Production of type phenolic resin B In the production of resin A, instead of allyl chloride,
The same procedure as in the production of Resin A was conducted except that 186 g of propargyl chloride was reacted. 298 g of propargyl etherified resol type phenol resin was obtained (hereinafter referred to as resin B). The propargyl etherification rate was 82% as measured by ¹ H-NMR.

Resol with a shielded phenolic hydroxyl group
Production of type phenolic resin C In the production of resin A, instead of allyl chloride,
The same procedure as in the production of Resin A was conducted except that 196 g of propyl chloride was reacted. 326 g of propyl etherified resol type phenol resin was obtained (hereinafter referred to as resin C).
The propyl etherification rate was 86% as measured by ¹ H-NMR.

Production of Resol-Type Phenolic Resin D Phenol 1000 was added to the reaction vessel used to produce Resin A.
g, 37% formalin 2700 g, calcium hydroxide 3
g was added and the temperature was gradually raised. After reacting at 70 ° C. for 2 hours, it was cooled to around room temperature, adjusted to pH 7.5 with sulfuric acid, dehydrated under vacuum, added with methyl ethyl ketone and filtered to obtain a resol-type phenol resin (hereinafter referred to as Resin D). To).

Production of Novolac Phenolic Resin E Phenol 1000 was added to the reaction vessel used to produce Resin A.
g, 37% formalin 716 g, and oxalic acid 10 g were added, and the temperature was gradually raised. After reacting under reflux for 5 hours, 150 at normal pressure
Distill the solution up to ℃, liquid temperature 150 ℃, under reduced pressure 50To
It was dehydrated until no distillate came out at rr. Softening point 101
A novolak-type phenol resin containing 3.7% of unreacted phenol at 0 ° C. was obtained (hereinafter referred to as resin E).

Examples 1 to 10 Polyamine and resin A, B or C were mixed at the ratio shown in Table 1 and heat treated at 130 ° C. for 2 hours and 200 ° C. for 5 hours. Each of the obtained treated products was crushed and the thermal decomposition start temperature was determined by thermogravimetric analysis. The results are shown in Table 1.

Comparative Examples 1 to 4 Resins A, B, C and D were heat treated and pulverized in the same manner as in Examples 1 to 10, and the thermal decomposition starting temperature was determined by thermogravimetric analysis. The results are shown in Table 1.

Comparative Example 5 Hexamethylenetetramine 1 was added to 100 parts by weight of Resin E.
0 part by weight was added, pulverized, mixed, and heat-treated at 130 ° C. for 2 hours and 200 ° C. for 5 hours. This was crushed and the thermolysis start temperature was determined by thermogravimetric analysis. The results are shown in Table 1.

[0032]

[Table 1]

Examples 11 to 13 and Comparative Example 6 A glass woven cloth (WL1 manufactured by Nitto Boseki Co., Ltd .;
80104) and then dried to prepare a prepreg having a resin impregnation rate of 25%. Eight of these prepregs were stacked and heated and pressed for 60 minutes in a hot plate press (180 ° C, 30 ° C).
kg / cm ² ) and further post-cured at 200 ° C. for 5 hours to obtain a laminated plate. A 250 ° C. heat deterioration test was performed on this laminated plate, and the time for maintaining a strength of 50% or more with respect to the normal bending strength was shown.

[0034]

[Table 2]

[0035]

Since the thermosetting resin composition according to the present invention has remarkably excellent heat resistance, it cannot be used in the conventional phenol resin because of insufficient heat resistance, for example, molding materials and laminates. , Mold material, resin felt, adhesive,
It can be widely used as a fiber treatment agent.

Claims (2)

[Claims] 1. A thermosetting resin composition comprising a resol-type phenol resin in which a phenolic hydroxyl group is shielded and a polyamine. 2. The thermosetting resin composition according to claim 1, wherein the weight ratio of the resol-type phenol resin having the phenolic hydroxyl group shielded to the polyamine is 1: 2 to 5: 1.