JPH06136079A - Phenolic resin molding material - Google Patents

Abstract

PURPOSE:To provide a phenolic resin molding material retaining inherent excellent characteristics such as curability, excellent in water resistance and flexibility, thus useful for bobbin molded products, etc., containing, as one component, a silicone-modified novolak resin produced using a specific modifier. CONSTITUTION:Firstly, a silicone-modified novolak resin is prepared by reaction, in the presence of an acid catalyst (e.g. hydrochloric acid, salicylic acid), between (A) a phenolic compound, (B) an aldehyde and (C) as modifier, a silicone- based addition polymer produced by reaction between (1) a hydrogenorganosiloxane of formula I (R1 and R2 are each alkyl or phenyl; n is 10-100) and (2) a polyfunctional aromatic polyallyl compound of formula II (R3 is H, halogen, etc.; R4 is of formula III, SO2, etc.) so as to be 10-50 pts.wt. of the component C based on 100 pts.wt. of the component A. The objective molding material contains the silicone-modified novolak resin as a part of phenolic resin. In making a reaction between the components A, B and C, it is preferable that e.g. an alcohol 80-200 deg.C in the boiling point at normal pressures be used as reaction solvent.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention provides a silicone-modified novolac resin as a component of a phenol resin and a glass fiber as a filler, which is excellent in curability and mechanical strength, and has excellent water resistance and flexibility. The present invention also relates to a phenol resin molding material having extremely excellent characteristics.

[0002]

2. Description of the Related Art Phenolic resin molding materials are excellent in heat resistance, dimensional stability, mechanical strength, moldability and the like, and have been used for a long period of time in basic industrial fields such as automobiles, electricity and electronics. In particular, recently, its application has been opened as a substitute material for metal parts in the field of automobiles, and the usage amount has been expanding more and more. However, since the phenolic resin has a hydrophilic hydroxyl group, when it is immersed in a polar solvent such as water or methanol for a long period of time, the dimensional change is large and small blister (swelling) occurs on the surface due to swelling. It cannot be applied to severe parts. In addition, thermosetting resin compositions such as phenolic resins have the advantage of being excellent in heat resistance, but also have the drawback of being brittle and easily cracked due to their cross-linked structure, which has hindered the expansion of application to metal parts. It is one of the reasons. As an attempt to improve these drawbacks, water resistance is improved by modification of a hydrophobic xylene resin or the like, and flexibility is improved by modification of various oils.

[0003]

The object of the present invention is to provide excellent water resistance and flexibility without deteriorating the excellent characteristics of the phenol resin molding material such as curability and mechanical strength. To provide a novel phenol resin molding material.

[0004]

MEANS FOR SOLVING THE PROBLEMS The present invention is represented by phenols (a), aldehydes (b), and hydrogenorganosiloxane represented by the following formula [I] as a modifier and the following formula [II]. The silicone-based addition polymer (c) obtained by reacting with a polyfunctional aromatic polyallyl compound is used in an amount of 10 to 50 parts by weight based on 100 parts by weight of the phenol (a). A phenol resin molding material, characterized in that a silicone-modified novolac resin obtained by reacting in the presence of an acid catalyst is used as a component of a phenol resin.

[0005]

[Chemical 1]

[0006]

[Chemical 2]

Each component used in the present invention will be described below. (Phenols) Phenols (a) used in the present invention
As, one or more selected from phenol, orthocresol, metacresol, paracresol, ethylphenol, xylenol, bisphenol A, bisphenol F, catechol, resorcinol, hydroquinone, propylphenol, propenylphenol, butylphenol, octylphenol, nonylphenol, or the like. There are two or more types. (Aldehydes) Aldehydes (b) used in the present invention
As formaldehyde, paraformaldehyde,
One or more selected from trioxane, acetaldehyde, benzaldehyde and the like.

(Polysiloxane-Aromatic Polyallyl Compound Addition Polymer) The polysiloxane-aromatic polyallyl compound addition polymer (c) used in the present invention usually comprises a hydrogenorganosiloxane and a polyfunctional aromatic polyallyl compound. It is a reaction product obtained by reacting in the presence of a platinum-based catalyst. The hydrogen organosiloxane used is a polysiloxane represented by the following formula [I],
The degree of polymerization (n) is in the range of 10 to 100.

[0009]

[Chemical 3]

When the degree of polymerization (n) is less than 10, the effect of improving the water resistance of the cured resin decreases, and when it exceeds 100, the reactivity with aldehydes decreases and it may be difficult to obtain a silicone-modified resin. The polyfunctional aromatic polyallyl compound has the formula [I
I], and the degree of polymerization (m) is in the range of 0-10.

[0011]

[Chemical 4]

When the degree of polymerization (m) exceeds 10, the effect of lowering the stress of the cured resin product is reduced. Further, the addition amount of the aromatic polyallyl compound to the polysiloxane is preferably 2 to 10 allyl groups in the aromatic polyallyl compound with respect to one hydrosilyl group in the polysiloxane. When it is less than 2, the molecular weight of the polysiloxane-aromatic polyallyl compound becomes too high and the reactivity with aldehydes is lowered, and unreacted silicone remains during the synthesis of the silicone-modified novolac resin, and the moisture resistance of the resin cured product is reduced. When it exceeds 10, the strength of the cured product decreases. The reaction method can be appropriately selected, and the catalyst at that time is preferably a platinum-based catalyst,
Particularly, an isopropanol solution of platinum chlorate is preferably used. After the reaction is complete, a liquid brown addition polymer is obtained at room temperature.

(Solvent) In the present invention, a solvent is usually used to homogenize the reaction system. As the type of solvent used, the boiling point at normal pressure is preferably 80 to 200 ° C.
1 or 2 or more selected from alcohols, ketones, ethers, esters, and cellosolves. (Acid catalyst) The acid catalyst used in the present invention includes hydrochloric acid,
One or more selected from sulfuric acid, benzoic acid, salicylic acid, paratoluenesulfonic acid, oxalic acid, phosphoric acid and the like.

Next, the formulation will be described. Aldehydes used in the production of the silicone-modified novolac are 0.5 to 1.0 mol per mol of phenols,
It is preferably in the range of 0.6 to 0.9 mol. When the amount is less than 0.5 mol, the molecular weight of the produced resin tends to be small and the mechanical strength tends to be lowered, and when it exceeds 1.0 mol, the melting point of the produced resin is high and the moldability becomes problematic. The amount of the polysiloxane-aromatic polyallyl compound addition polymer added to 100 parts by weight of the phenol is 10 to 50 parts by weight, preferably 20 to 40 parts by weight. If it is less than 10 parts by weight, the effect of improving the water resistance is small, and if it exceeds 40 parts by weight, the strength is lowered.

The amount of the solvent used is preferably 5 to 200 parts by weight with respect to 100 parts of phenols, and more preferably 1 part.
It is 0 to 100 parts by weight. If the amount of the solvent used is less than 5 parts by weight, it is difficult for the reaction solution to become a homogeneous system during the modification reaction, and unreacted silicone tends to remain, and if it exceeds 200 parts by weight, the concentration of the reaction solution decreases and the reactivity becomes low. And the unreacted silicone tends to remain, which is not preferable. The amount of the acid catalyst used is in the range of 0.1 to 10 parts by weight, preferably 0.2 to 5 parts by weight, based on 100 parts by weight of phenols. The reaction method is the same as in the case of a normal novolac resin. For example, at a reaction temperature of 60 to 200 ° C, 1 to 20
Perform the dehydration condensation reaction for an hour.

Next, the phenol resin used in combination with this silicone-modified novolak is a normal random novolak,
High ortho novolac, methylol resole, dimethylene ether resole, and the like, which are further modified with an alkylphenol such as cresol and an alkylbenzene such as xylene can be used, and they can be used in combination. As the filler, clay, alumina, calcium carbonate, diatomaceous earth, mica, glass fiber, glass flake or the like can be used alone or in combination. Among them, when glass fiber is used as a main component, it is possible to obtain excellent mechanical strength and extremely excellent water resistance and flexibility.

Furthermore, in order to prevent the ingress of polar solvent such as water and alcohol from the interface between the resin and the filler, aminosilane,
Use of a silane coupling agent such as epoxysilane is more effective for water resistance. As a resin component, an ordinary phenol resin is blended in an arbitrary ratio with a silicone-modified novolac, and a filler is blended in an amount of 50 to 200 parts by weight with respect to 100 parts by weight of a resin component. Agents, release agents, pigments, etc. are added. A phenol resin molding material is obtained by uniformly mixing these raw materials, heating and kneading them with a kneader such as a roll, kneader, or twin-screw extruder, and pulverizing with a pulverizer.

[0018]

【Example】

<< Reference Example 1 >> (Synthesis of Addition Polymer of Polysiloxane-Aromatic Polyallyl Compound) 1% by weight of isopropanol chloroplatinate solution in 100 parts by weight of hydrogen dimethylpolysiloxane having hydrogen groups at both ends having an average degree of polymerization of 10 Was added to 2 parts by weight and heated to 90 ° C. To this, 60 parts by weight of O, O'-diallylbisphenol A was added dropwise over 1 hour,
Then, the system was heated to 100 ° C. and the reaction was continued for 3 hours. After cooling, an addition polymer having a viscosity of 12700 cps was obtained.

Example 1 100 parts of phenol, 65 parts of 37% formalin (0.75 mol per 1 mol of phenol) were placed in a reactor equipped with a stirrer, a heat exchanger, and a thermometer. 30 parts of an addition polymer of polysiloxane-aromatic polyallyl compound, 100 parts of methyl isobutyl ketone as a solvent, and 1 part of oxalic acid as a catalyst were charged, and a reflux reaction was carried out at normal pressure for 300 minutes.
The initial condensation reaction was completed by performing dehydration reaction at atmospheric pressure until the temperature reached 55 ° C. After that, the liquid temperature is 155 ° C and the vacuum degree is 60To.
A dehydration condensation reaction was performed for 1 hour at rr to obtain a silicone-modified novolac resin having a softening point of 92 ° C.

Example 2 50 parts of meta-cresol, 50 parts of para-cresol, 49 parts of 37% formalin (0.65 mol to 1 mol of cresol) in a reactor equipped with a stirrer, heat exchanger and thermometer, reference Polysiloxane-aromatic polyallyl compound addition polymer 30 obtained according to Example 1
Parts, and 100 parts of methyl isobutyl ketone as a solvent,
0.5 parts of oxalic acid was charged as a catalyst, a reflux reaction was carried out at normal pressure for 300 minutes, and then a dehydration reaction was carried out at normal pressure until the liquid temperature reached 155 ° C. to complete the initial condensation reaction. Then, a dehydration condensation reaction was performed for 1 hour at a liquid temperature of 155 ° C. and a vacuum degree of 60 Torr to obtain a silicone-modified novolac resin having a softening point of 91 ° C.

Example 3 The silicone-modified novolak of Example 1 and the novolak of Comparative Example 1 were blended in a ratio of 1: 1 (weight ratio). << Example 4 >> The silicone-modified novoc of Example 1 and the novolak of Comparative Example 1 were blended in a ratio of 1: 1 (weight ratio).

Comparative Example 1 100 parts of phenol, 65 parts of 37% formalin (0.75 mol per 1 mol of phenol), and 1 part of oxalic acid as a catalyst were charged in a reactor equipped with a stirrer, a heat exchanger and a thermometer. After carrying out a reflux reaction for 90 minutes under normal pressure, a dehydration reaction was carried out under normal pressure until the liquid temperature reached 155 ° C. to complete the initial condensation reaction. After that, the liquid temperature is 155
A novolak resin having a softening point of 92 ° C. was obtained by performing a dehydration condensation reaction at a temperature of 60 ° C. and a vacuum degree of 60 Torr.

Comparative Example 2 100 parts of phenol, 65 parts of 37% formalin (0.75 mol per 1 mol of phenol) were placed in a reactor equipped with a stirrer, a heat exchanger, and a thermometer. Charge 5 parts of an addition polymer of polysiloxane-aromatic polyallyl compound, 100 parts of methyl isobutyl ketone as a solvent, and 1 part of oxalic acid as a catalyst.
After performing the reflux reaction for 300 minutes at normal pressure, the liquid temperature is 155.
The initial condensation reaction was completed by performing dehydration reaction at atmospheric pressure until the temperature reached. Then, a dehydration condensation reaction was performed for 1 hour at a liquid temperature of 155 ° C. and a vacuum degree of 60 Torr to obtain a silicone-modified novolac resin having a softening point of 93 ° C.

Comparative Example 3 100 parts of phenol, 65 parts of 37% formalin (0.75 mol per mol of phenol) were placed in a reactor equipped with a stirrer, a heat exchanger, and a thermometer. After adding 60 parts of an addition polymer of polysiloxane-aromatic polyallyl compound, 100 parts of methyl isobutyl ketone as a solvent, and 1 part of oxalic acid as a catalyst, a reflux reaction was carried out at normal pressure for 300 minutes, and then the liquid temperature was 1
The initial condensation reaction was completed by performing dehydration reaction at atmospheric pressure until the temperature reached 55 ° C. After that, the liquid temperature is 155 ° C and the vacuum degree is 60To.
A dehydration condensation reaction was carried out at rr for 1 hour to obtain a silicone-modified novolac resin having a softening point of 82 ° C.

The silicone-modified novolac resin or novolac resin 10 obtained in each of the above Examples and Comparative Examples
Hexamine (10 parts) was added to 0 part and mixed, and finely ground to a powder resin so that the 105 μm sieve residue was 1.0% or less. The melting point, flow, and gelation time of powdered resin can be measured according to JIS K 6
It was measured by the method of 909. The measurement results are as shown in Table 1.

[0026]

[Table 1]

Next, these silicone-modified novolac resins or novolac resins were made into molding materials with the formulations shown in Table 2. The molding material is kneaded using two rolls,
It was manufactured by crushing after cooling.

[Table 2]

With respect to the obtained molding material, a test piece was molded by transfer molding using a mold of 175 ° C., and the performance of the obtained molding was measured. The results are shown in Table 3. The test piece is evaluated according to JIS K 691.
Performed according to 1.

[Table 3]

[0029]

The phenol resin molding material using the silicone-modified novolac resin according to the present invention is water resistant without impairing many excellent features such as curability and mechanical strength of ordinary novolac resins. It is possible to obtain a molding material having extremely good properties and flexibility. Therefore,
It is suitable for molded products that are immersed in water, polar dissolution, etc. for a long period of time, and bobbin molded products that require the strength of the flange portion.

Claims (1)

[Claims] 1. Phenols (a), aldehydes (b),
And a silicone-based addition polymer (c) obtained by reacting a hydrogen organosiloxane represented by the following formula [I] with a polyfunctional aromatic polyallyl compound represented by the following formula [II] as a modifier 10 to 100 parts by weight of (a) the silicone-based addition polymer (c)
A phenol resin molding material, which comprises a silicone-modified novolac resin obtained by reacting in the presence of an acid catalyst in an amount of 50 parts by weight as one component of a phenol resin. [Chemical 1] [Chemical 2]