JPH07138454A - Phenolic resin molding material and molded article - Google Patents

Abstract

PURPOSE:To obtain an asbestos-free phenolic resin molding material containing a condensed-type phenol-aralkyl resin and an inorganic filler as essential components at respective specific ratios, having excellent heat-resistance, mechanical properties, etc., and useful for electronic and electric parts, etc. CONSTITUTION:This molding material contains (A) a condensed-type phenol- aralkyl resin of the formula (R is H or an alkyl; Z is H, CH2 or CH2OCH2; (x) and (y) are integers of 0 or 1-2 and x+ynot equal to 0; (n) is an integer of >=1) and (B) an inorganic filler (other than asbestos; e.g. calcium carbonate, clay or talc) as essential components. The amounts of the component A and the component B are 5-70wt.% and 95-30wt.% based on the total molding material, respectively.

Description

Detailed Description of the Invention

[0001]

The present invention is asbestos-free,
The present invention relates to a phenol resin molding material having excellent heat resistance, mechanical properties, and electrical characteristics, and a phenol resin molded product obtained by molding the same.

[0002]

2. Description of the Related Art Conventionally, a phenol resin has been widely used as a molding material by mixing and kneading it with a base material, a plasticizer, a coloring agent, a release agent and the like. The phenol resin molding material thus obtained is a material that is well-balanced in heat resistance, mechanical and electrical characteristics, but recently, due to the expansion of its applications, it is necessary to improve the level of various electrical characteristics. There is.

Asbestos has been used as a base material for phenol resin molding materials which satisfy such many characteristics. Asbestos is used as a suitable base material because it has excellent heat resistance, electrical characteristics, and mechanical strength, and provides well-balanced characteristics. However, recently, the use of asbestos is prohibited because it deteriorates the working environment and is harmful to the human body.
For these reasons, various methods have been investigated as an asbestos-free material, but a satisfactory method has not been obtained yet.

Further, the conventional phenol resin molding material is
Since it is insufficient in terms of long-term heat resistance, recently, one using hexamethylenetetramine as a curing agent for phenol aralkyl resin, one obtained by combining phenol aralkyl resin and novolac type phenol resin and curing with hexamethylenetetramine, Has attempted a phenol resin molding material using a phenol-aralkyl resin and a resol-type phenol resin as a curing agent.

However, when hexamethylenetetramine is used alone or in combination with a novolak type phenolic resin, phenol aralkyl resin is excellent in long-term heat resistance, mechanical strength or electrical characteristics and has a good balance of characteristics, It had the drawback of not being free. Further, when a resol-type phenol resin is used as a curing agent for the phenol aralkyl resin, the properties are well balanced and ammonia-free, but there is a drawback that the curing properties during molding are poor.

[0006]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances and is asbestos-free and ammonia-free, which is excellent in long-term heat resistance and mechanical / electrical characteristics, and has a good balance of characteristics. It is intended to provide a good phenol resin molding material and a molded product thereof.

[0007]

Means for Solving the Problems As a result of intensive studies to achieve the above object, the present inventors have found that the above object is achieved by using a specific condensed phenol aralkyl resin. The present invention has been completed.

That is, the present invention provides (A) a condensed phenol aralkyl resin represented by the following formula:

[0009]

[Chemical 3]

[0010] (wherein, the formula, R represents a hydrogen atom or an alkyl group, Z is H -, - CH ₂ - or -CH ₂ OCH ₂ -, and
x and y are x + y ≠ 0 and 0 or an integer of 1 to 2
Represents an integer of 1 or more.) (B) Inorganic filler is an essential component, and 5 to 70% by weight of the above-mentioned (A) phenol aralkyl resin relative to the entire molding material, and (B) the inorganic filler. A phenol resin composition characterized by containing 95 to 30% by weight and a phenol resin molded product obtained by molding the phenol resin composition.

The present invention will be described in detail below.

The condensed phenol aralkyl resin (A) used in the present invention is represented by the above-mentioned general formula 3, and the phenol aralkyl resin and formalin or paraformaldehyde are mixed at an appropriate molar ratio to obtain a catalyst. The resin and its condensate obtained by reacting with. The condensate phenol alkyl resin is preferably compounded in such an amount that it is contained in an amount of 5 to 70% by weight based on the entire phenol resin composition. If the blending ratio is out of this range, the flow characteristics are poor and it is not preferable.

The inorganic filler (B) used in the present invention is not particularly limited as long as it is other than asbestos and can be widely used. Examples thereof include calcium carbonate, clay, talc, silica, glass fiber and the like. These can be used alone or in combination of two or more,
Moreover, it suffices if these can be mixed in a good balance. It is desirable to mix the inorganic filler so that it is contained in an amount of 30 to 95% by weight based on the whole phenol resin molding material. If the blending ratio is less than 30% by weight, the mechanical strength is lowered, and if it exceeds 95% by weight, it cannot be uniformly dispersed in the phenol resin molding material, which is not preferable.

The phenolic resin molding material of the present invention contains the above-mentioned specific condensation type phenol aralkyl resin and the inorganic filler as essential components. However, as long as it does not defeat the purpose of the present invention, and if necessary, a curing accelerator. ,Release agent,
Additives such as flame retardants, lubricants, coupling agents and the like can be appropriately added and blended.

The phenol resin molding material of the present invention is usually manufactured as follows. The above-mentioned specific condensed phenol aralkyl resin, the inorganic filler and other additives as required are added and mixed, and after uniformly dispersing, the mixture is heated and kneaded by a kneader and then cooled and solidified to a suitable size. It is crushed to a molding material. Further, this phenol resin molding material can be molded into a molded product.

[0016]

The phenol resin composition of the present invention improves the long-term heat resistance and mechanical properties, retains electrical properties, and has excellent curing properties by using a specific condensation-type phenol aralkyl resin. free,
A phenol resin molding material which is ammonia-free and has well-balanced properties and a molded article thereof can be obtained.

[0017]

EXAMPLES Next, the present invention will be described with reference to examples, but the present invention is not limited to these examples. In the following examples and comparative examples, “%” means “% by weight”.

Example 1 30% of the condensation type phenol aralkyl resin of Chemical formula 3, 60% of glass fiber and 10% of other additives were mixed at room temperature, and further 90%
After kneading and cooling at ~ 110 ° C, it was pulverized to produce a phenol resin molding material.

Example 2 30% of the condensation type phenol aralkyl resin of Chemical formula 3, 25% of kaolin clay, 35% of glass fiber and 10% of other additives were mixed at room temperature, further kneaded and cooled at 90 to 110 ° C., It was crushed to produce a phenol resin molding material.

Comparative Example 1 30% of resol type phenolic resin, 60% of glass fiber and 10% of other additives were mixed at room temperature, kneaded and cooled at 90 to 110 ° C., and then pulverized to produce a phenolic resin molding material. did.

Comparative Example 2 Phenol aralkyl resin (27%), hexamethylenetetramine (3%), glass fiber (60%) and other additives (10%) were mixed at room temperature, kneaded and cooled at 90 to 110 ° C., and then pulverized to obtain phenol. A resin molding material was manufactured.

Comparative Example 3 Phenol aralkyl resin 22%, resol type phenol resin 8%, glass fiber 30%, asbestos 30% and other additives 10% were mixed at room temperature, and after further kneading and cooling at 90 to 110 ° C. Then, it was pulverized to produce a phenol resin molding material.

Comparative Example 4 Phenol aralkyl resin 18%, resol type phenol resin 6%, novolac type phenol resin 4%, hexamethylenetetramine 2%, glass fiber 60% and other additives 10% were mixed at room temperature, and further mixed. After kneading and cooling at 90 to 110 ° C, it was pulverized to produce a phenol resin molding material.

Using the phenolic resin molding materials produced in Examples 1 and 2 and Comparative Examples 1 to 4, they were molded and cured in a mold heated to 170 ° C. by compression molding and injection molding to obtain molded parts, and 180 ° C. × 3 Hr +220 ° C × 4 Hr +250 ° C × 4 H
Post-curing was carried out under the condition of r + 270 ° C. × 2 Hr. The obtained molded product was tested for mechanical properties, electrical properties, and curing properties. The results are shown in Table 1. The present invention shows excellent properties and well-balanced properties. The effect of the invention could be confirmed.

[0025]

[Table 1] * 1: The half-life of bending strength at 250 ° C treatment was calculated. * 2: A 6 mm-thick test piece was molded by injection molding, and the minimum curing time without blistering was determined.

[0026]

As is apparent from the above description and Table 1, the phenolic resin molding material of the present invention and its molded article are asbestos-free and have excellent heat resistance, mechanical / electrical characteristics, and appearance, and a property balance. And is suitable for electronic / electrical parts, automobile parts, and the like.

Claims (2)

[Claims] 1. A condensed phenol aralkyl resin represented by the following formula (A): (However, in the formula, R represents a hydrogen atom or an alkyl group, and Z represents H.
-, - CH ₂ - or -CH ₂ OCH ₂ - a, x, y are x
+ Y ≠ 0 and 0 or an integer of 1 to 2 and n is an integer of 1 or more, respectively. (B) An inorganic filler is an essential component, and the above-mentioned (A) phenol aralkyl is added to the entire molding material. 5 to 70% by weight of resin, (B)
A phenol resin molding material comprising 95 to 30% by weight of the above inorganic filler. 2. (A) a condensed phenol aralkyl resin represented by the following formula: (However, in the formula, R represents a hydrogen atom or an alkyl group, and Z represents H.
-, - CH ₂ - or -CH ₂ OCH ₂ - a, x, y are x
+ Y ≠ 0 and 0 or an integer of 1 to 2 and n is an integer of 1 or more, respectively. (B) An inorganic filler is an essential component, and the above-mentioned (A) phenol aralkyl is added to the entire molding material. 5 to 70% by weight of resin, (B)
A phenol resin molded article, which is obtained by molding a phenol resin molding material containing 95 to 30% by weight of the inorganic filler.