JPH0925392A - Phenol resin composition excellent in heat resistance - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a phenol resin excellent in heat resistance by adding a halogenated organic flame retardant and an inorganic flame-retardant synergist to a blend of a phenol resin, a resol resin, a specified novolak phenol resin and other component. SOLUTION: 100 pts.wt. phenol resin (A) having a benzene ring and a polycyclic aromatic skeleton is blended with 30-80 pts.wt. resol resin (B) comprising dimethylene ether, 30-80 pts.wt. novolak phenol resin (C) wherein the ratio of the content of the methylene linkages at the ortho positions of the phenol nuclei to that at the para positions is 1.5 to 2.5, 5-30 pts.wt. hexamethylenetetramine (D), and a halogenated organic flame retardant (E) alone or together with an inorganic flame-retardant synergist (F) comprising, e.g. SbO3 , or MoO3 , to produce a heatresistant phenol resin molding material. Preferably in addition, 100 pts.wt. of this composition is blended with 5-30 pts.wt. NBR and vinyl acetate resin. The component A preferably comprises one having a number-average molecular weight of about 1,500 to 2,500. The component B preferably comprises one having a phenol content of at most 2%. The component E preferably comprises a brominated organic flame retardant.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a phenol resin composition having excellent heat resistance and a molding material using the same.

[0002]

2. Description of the Related Art Phenolic resin molding materials are excellent in heat resistance, dimensional stability, moldability and the like, and have been used for a long time in basic industrial fields such as automobiles, electricity and electronics. Especially,
Recently, the usage as an alternative material for various metal parts in the automobile field and the like has been opened, and the usage amount is expanding more and more. However, with the rise in the required heat resistant temperature level, there are some cases in which conventional phenolic resins cannot be used.

As a means for improving this, baking treatment is performed with the intention of increasing the crosslink density of the molded product, or phenolic OH as disclosed in, for example, JP-A-60-35047 and JP-A-2-55203. A novolak type phenolic resin with a structure containing few groups has been developed, and Japanese Patent Application No. 5-1
As described in Japanese Patent Application No. 76817 and Japanese Patent Application No. 5-253402, a phenol resin molding material in which a resol resin or polyvinyl phenol is used in combination with a novolac type phenol resin having a structure having a small number of phenolic OH groups has been developed. There was an insufficient balance between heat deterioration resistance and thermal rigidity, there was a problem in moldability (particularly curability), and there was a limit in heat resistance.

[0004]

DISCLOSURE OF THE INVENTION The present invention has been made as a result of various studies in order to solve such problems of the conventional phenol resin composition or phenol resin molding material, and its object is to achieve the object. Is to provide a phenolic resin composition and a molding material which are remarkably excellent in heat-resistant aging characteristics and thermal rigidity without deteriorating molding processability.

[0005]

According to the present invention, 100 parts by weight of a phenol resin having a skeleton of benzene, phenol and polycyclic aromatics is added to a dimethylene ether type resol resin 3
0 to 80 parts by weight, 30 to 80 parts by weight of a novolac type phenolic resin having a ratio of ortho-bonds to para-bonds of 1.5 to 2.5 in a methylene bond bonded to a phenol nucleus, and hexamethylenetetramine 5 to 30 Blending parts by weight,
Furthermore, the present invention relates to a heat-resistant phenol resin composition characterized in that a halogen-based organic flame retardant is used alone or in combination with an inorganic flame retardant synergist such as antimony trioxide and molybdenum trioxide. 100 in total
1 selected from NBR and vinyl acetate resin with respect to parts by weight
Or 2 to 5 parts by weight of a heat resistant phenolic resin composition, and further 100 to 100 parts by weight of these compositions, glass fiber and other inorganic fillers 150 to 500
The present invention relates to a heat-resistant phenolic resin molding material containing parts by weight.

The phenolic resin having benzene, phenol and polycyclic aromatic skeleton (hereinafter abbreviated as polycyclic phenol resin) used herein is represented by the following chemical formula (1).
And / or (2) is a basic skeleton, which is a phenolic resin that reacts with a curing agent such as hexamethylenetetramine and three-dimensionally crosslinks and cures. There are various types, but in the present invention, a molding material is used. The number average molecular weight is about 1500 to 2500 and the softening point is 70 because of the ease of handling.
It is desirable that the temperature is about 80 ° C, for example, the trade name SKR
-H17 (Sumikin Kako Co., Ltd., number average molecular weight about 200)
0, softening point approx. 70 ° C, free phenol content 1.0
%) Is an example.

[0007]

Embedded image In the chemical formulas (1) and (2), (Aro) represents a phenyl group or a polycyclic aromatic group, X represents H, OH or an alkyl group, and each (Aro) and X are the same. May also be different.

As the resole resin, an ordinary dimethylene ether type resole resin can be used, and the present invention is not limited to the above. However, when a resin having a phenol content of 2.0% or less is used, the heat resistance is further improved. To do. As the novolac resin, a novolac-type phenol resin having a ratio of ortho-bonds to para-bonds of 1.5 to 2.5 in the methylene bond bonded to the phenol nucleus can be used, and the ratio of ortho-bonds to para-bonds is 1. .5-2.5 is preferable. When the binding ratio is 1.5 or less, the curability is lowered, and when it is 2.5 or more, the resin itself can be technically produced, but it is not economically practical. In the present invention, in order to further improve heat resistance, a halogen-based organic flame retardant is used alone or in an antimony trioxide in a resin composition comprising the above components,
Used in combination with an inorganic flame retardant synergist such as molybdenum trioxide. As halogen-based organic flame retardants, various types such as brominated organic flame retardants and chlorine-based organic flame retardants are commercially available. There is an effect, for example, for bromine-based products, trade name Pirocheck PC-68PB (FERR
O), Pyroguard SR-245 (Daiichi Kogyo Seiyaku Co., Ltd.), and chlorine-based products under the trade name Dechlorane Plus 25.
(Occidental Chemical Co., Ltd.) is an example.

Next, the blending ratio of these will be described. The dimethylene ether type resole resin to be added to improve the rigidity during heating is preferably 30 to 80 parts by weight with respect to 100 parts by weight of the polycyclic phenol resin. If it is 80 parts by weight or more, the heat deterioration resistance is lowered, and if it is 30 parts by weight or less, the rigidity under heat is lowered. 30 to 80 parts by weight of the novolac-type phenol resin having a ratio of ortho to para bonds of 1.5 to 2.5 in the methylene bonds bonded to the phenol nuclei to improve the curability is preferable. When it is 80 parts by weight or more, the heat deterioration resistance is lowered, and when it is 30 parts by weight or less, the curability is lowered. Hexamethylenetetramine is preferably 5 to 30 parts by weight. If the amount is 30 parts by weight or more, the moldability decreases, and if it is 5 parts by weight or less, the curability decreases.

In order to improve heat deterioration resistance, NB
One or two kinds selected from R and vinyl acetate resin can be blended, and one kind or two kinds selected from NBR and vinyl acetate resin is 5 to 100 parts by weight of the phenol resin composition. 30 parts by weight is preferred. If it is 5 parts by weight or less, the heat deterioration resistance is lowered, and if it is 30 parts by weight or more, the thermal rigidity is lowered. As NBR, commercially available ones can be used, but there are ones that are cross-linked in the molecule, ones having a functional group such as carboxyl, and the like, and any one can be used. When used as a molding material, a solid or powdery material is preferable in handling, and an SP value of about 9 to 10 is more preferable in terms of compatibility with a resin. Commercially available vinyl acetate resin can be used, but when used as a molding material, a solid or powdery one is preferable in terms of handling, and a polymerization degree of 2000 or more is more preferable.
000 or more is desirable. Further, if necessary, a modified vinyl acetate resin such as a vinyl acetate-ethylene copolymer, a vinyl acetate-acrylic copolymer, a vinyl acetate-epoxy copolymer can be used.

The above-mentioned composition makes it possible to obtain a phenol resin composition having excellent properties such as excellent heat resistance, curability, and rigidity when heated, and little thermal deterioration.

The phenol resin composition can be used in various applications requiring heat resistance, such as molding materials, laminated plates, various binders, compounding agents for other resins, etc. It is suitable for use as a molding material containing an inorganic filler as a main component. In such a molding material, the amount of the inorganic filler is preferably 150 to 500 parts by weight with respect to 100 parts by weight of the phenol resin composition. If it is less than 150 parts by weight, the elastic modulus is low and the creep deformation amount is large, and if it is more than 500 parts by weight, it becomes difficult to use it as a molding material and the molding processability also deteriorates. The blending amount of glass fiber is 50% by weight in the inorganic filler from the viewpoint of mechanical strength.
The above is preferred.

The phenol resin molding material in the present invention is prepared by adding pigments, mold release agents, curing accelerators, etc., which are used in ordinary phenol resin molding materials, in addition to these compounding compositions, and after uniformly mixing these raw materials. It is produced by heating and kneading with a kneader such as a roll, a co-kneader, or a twin-screw extruder, and then pulverizing. The phenol resin composition of the present invention is particularly excellent in heat resistance, has little thermal deterioration, and has other good properties, so that the molding material obtained therefrom can withstand use in a high-temperature environment for a long time and can be used for automobile parts. It is extremely suitable for making various metal parts such as resin.

[0014]

EXAMPLE A molding material was obtained by heating and kneading with a conventional two-roll with the composition shown in Examples and Comparative Examples of Table 1. The characteristics of the molded products were measured for these molding materials, and the results shown in Table 2 were obtained.

[0015]

[Table 1]

[0016]

[Table 2]

(Measurement Method) Bacol Hardness Retention Rate: To evaluate heat resistance, Bacol hardness retention rate at room temperature was measured as a method for measuring surface deterioration. Flexural strength, flexural modulus: 17 by transfer molding method
Molded at 5 ° C for 3 minutes, and 2 according to JIS K7203
It was measured at 50 ° C. Bacol hardness during heating: As a method of measuring curability from the surface cross-linking density, 175 ° C., 3 by transfer molding method
After molding for 0 seconds, Bacol hardness was measured 10 seconds after the molding.

[0018]

INDUSTRIAL APPLICABILITY The phenol resin composition or the phenol resin molding material of the present invention has excellent heat resistance as well as curability and mechanical strength as compared with conventional phenol resin compositions or phenol resin molding materials. Since it is equal to or more than the molding material, it is extremely suitable for resinification of various metal parts including automobile parts.

Claims (3)

[Claims] 1. 100 parts by weight of a phenol resin having benzene, phenol and a polycyclic aromatic group as a skeleton, 30 to 80 parts by weight of a dimethylene ether type resole resin, and an ortho bond and a para bond in a methylene bond bonded to a phenol nucleus. Novolac type pheno with a ratio of 1.5 to 2.5
Resin 30 to 80 parts by weight and hexamethylenetetramine 5 to 30 parts by weight, and a halogen-based organic flame retardant alone or in combination with an inorganic flame retardant synergist such as antimony trioxide or molybdenum trioxide. A heat-resistant phenolic resin composition characterized by: 2. The phenolic resin composition 1 according to claim 1.
A heat resistant phenolic resin molding material, characterized in that 5 to 30 parts by weight of one kind or two kinds selected from NBR and vinyl acetate resin is mixed with 00 parts by weight. 3. The phenolic resin composition 1 according to claim 1.
Glass fiber and other inorganic fillers per 100 parts by weight 1
A heat-resistant phenolic resin molding material, characterized by being mixed in an amount of 50 to 500 parts by weight.