JPH0987524A - Tough phenolic resin composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a tough phenolic resin composition in which crosslinked functional-group-containing liquid diene rubber particles are dispersed. SOLUTION: A functional-group-containing liquid diene rubber together with an organosilicone crosslinking agent and a hydrosilylation catalyst is melt- kneaded in a novolac phenolic resin, and the entire is dynamically crosslinked to disperse particles of the rubber. The modified novolac phenolic resin can be used as a toughened molding material or a material for electrical circuits. The functional-group-containing liquid diene rubber should have a Brookfield viscosity of 0.001-500Pa-sec. at the temperature at which the resin melts.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a molding material, a laminate,
The present invention relates to a toughened phenol resin composition which is preferably used as a curing agent for epoxy resins.

[0002]

2. Description of the Related Art Phenolic resins have been widely used alone or in combination with other resins. Especially, they have good electric insulation, sufficient mechanical strength, good heat resistance, and thermal expansion coefficient. It is widely used for electrical parts or mechanical parts because of its advantages such as low heat resistance, flame retardancy, and low cost. On the other hand, low toughness, which is a common drawback of thermosetting resins, is also the greatest drawback of phenolic resins, and various studies have been made from various viewpoints.

For example, in JP-A-61-168652, the impact resistance of a specific phenolic resin is improved by an aromatic polyester, and in JP-A-62-209158, a specific polyethylene terephthalate, polyurethane, and methyl methacrylate-based copolymer is used. Although toughening of a phenolic resin by a polymer or the like has been studied, these products are extremely unsatisfactory such as insufficient improvement in toughness and deterioration in fluidity. Further, an emulsion polymerization latex of a functional rubber having an epoxy group, a hydroxyl group, a carboxyl group and an amino group is kneaded into a phenol resin.
No. 2-59660 or JP-A-3-17149 in which a conjugated diene rubber latex such as NBR having a good compatibility is contained in an anionic surfactant and then dispersed in the resin before the dehydration step of the phenol resin. Although this method can strengthen the toughness of the phenolic resin, adding rubber to such an extent that the toughening effect is effective will drastically reduce the fluidity, thus impairing the practical formability. In addition, the surfactant used for atomizing the rubber itself has the problem of impairing long-term electrical reliability and mechanical reliability, and there have been no cases where conventional toughness and other properties are harmonized. Didn't.

Further, in the production of phenol molding material,
JP-A-3-221555, in which an epoxidized polybutadiene and a radical polymerization initiator are blended at the time of kneading a molding material, has also been proposed, but since the phenol resin has a function of trapping a radical, the usage of the radical polymerization initiator is restricted. However, there is a problem that the characteristics cannot be reproduced due to the presence of a third component such as organic / inorganic fillers such as cloth chips and glass fibers, mold release agents, and the kneading conditions of equipment. It was necessary to determine the cross-linking state and dispersion state of rubber particles in advance, and to develop a tough resin that does not cause characteristic changes in the subsequent process.

[0005]

SUMMARY OF THE INVENTION An object of the present invention is to provide a tough phenol resin composition useful for molding materials, laminates, curing agents, etc., which has not been obtained by the prior art.

[0006]

[Means for Solving the Problems] In order to solve the above problems, as a result of various investigations, as a result, a diene liquid rubber having a functional group, in particular, having a specific functional group and having a specific melt viscosity The liquid rubber in the range can be uniformly dispersed in the resin by kneading, and can be crosslinked using an organic silicone crosslinking agent and a hydrosilylation catalyst to crosslink the dispersed liquid rubber into stable particles. I found a thing. Further, the dispersed particles of the crosslinked rubber exhibit stable compatibility by the functional group having an affinity with the resin or by reacting with the resin, and the use of this resin does not affect other properties. It was found that a molding material exhibiting tough characteristics, a laminate, a curing agent for epoxy resin, and the like can be obtained, and the present invention has been completed.

That is, the present invention comprises melt-kneading a novolac type phenol resin (a), a diene liquid rubber (b) having a functional group, an organic silicone cross-linking agent (c) and a hydrosilylation catalyst (d). The present invention relates to a tough phenol resin composition characterized by the above.

The novolak type phenolic resin (a) used as the raw material of the present invention is not particularly limited and is commercially available. For example, phenols and formalin are used, and phenols and formaldehyde are used in a molar ratio of The mixture was charged into a reaction kettle at a compounding ratio of 0.5 to 1.0, and a catalyst such as oxalic acid, hydrochloric acid, sulfuric acid, and toluenesulfonic acid was further added, and the mixture was heated and refluxed for an appropriate time. It can be obtained by a method such as vacuum dehydration or static dehydration for removing separated water, and further removing remaining water and unreacted phenols. These resins or co-condensed phenol resins obtained by using a plurality of raw material components are used alone or in combination of two or more.

The diene liquid rubber (b) having a functional group, which is used as a raw material of the present invention, is generally commercially available, and is polybutadiene, polyisoprene, polychloroprene, butadiene-isoprene copolymer, butadiene-styrene copolymer. A polymer, an acrylonitrile-butadiene copolymer, a polymer comprising at least one selected from natural rubber, or a partially hydrogenated product thereof,
It is necessary to have one selected from a hydroxyl group, an epoxy group, an N-methylol group, an amino group, a carboxyl group, or an acid anhydride group. The position of the functional group in the rubber molecule is not particularly limited, and it may be at the terminal position or at a position other than the terminal position. Further, the diene rubber having this functional group has a Brookfield viscosity of 0.001 to 500 Pa · Sec at the melting point of the phenol novolac resin, and
It may be a single kind or a blend of two or more kinds.

The organosilicone cross-linking agent (c) used as a raw material of the present invention is a silicone compound having two or more SiH groups in the molecule, a derivative compound thereof or a polymer derived from the silicone compound. Crosslinking is carried out by utilizing a selective addition reaction to unsaturated hydrocarbons. In order to be a cross-linking agent, it is necessary to add to two or more molecules of rubber, so it is necessary to have two or more SiH groups in the molecule. Specific examples of the compound include a compound having a structure of a cyclic polysiloxane (I), a linear polysiloxane (II), and a tetrahedral siloxane (III) as shown below. Further, a compound and / or a polymer derived from the compound may be used.

Cyclic polysiloxanes (I)

Embedded image Linear polysiloxanes (II)

Embedded image Tetrahedral siloxanes (III)

Embedded image (M is an integer of 3 to 20, n is an integer of 0 to 50, R is hydrogen, an alkyl group, an alkoxy group, an aryl group or an aryloxy group, and at least one R bonded to a silicon atom is The hydrogen atom has two or more silicon atoms in the molecule.) The hydrosilylation catalyst (d) refers to all catalysts that accelerate the hydrosilylation reaction, and examples thereof include noble metals such as chloroplatinic acid. Examples include system catalysts and peroxides.

To the phenol resin composition of the present invention, a novolac type phenol resin (a), a diene liquid rubber (b) having a functional group, an organic silicone crosslinking agent (c) and a hydrosilylation catalyst (d) are added. The rubber portion is dynamically crosslinked by melt-mixing the compounded mixture with a pressure kneader, a twin-screw kneader, or the like. A preferable compounded range is the novolac type phenol resin (a) The diene liquid rubber (b) having a functional group is 99: 1 to 50: 5.
0 parts by weight, preferably 90:10 to 60:40 parts by weight,
More preferably, it is used in the range of 85:15 to 65:35 parts by weight. When the compounding ratio of the diene liquid rubber (b) having a functional group is less than 1 part by weight, the effect of improving properties such as bending strength and impact resistance tends to be insufficient, and when it exceeds 50 parts by weight, Liquidity tends to decrease.

The organic silicone crosslinking agent (c) is rubber 1
It is compounded in a ratio necessary to crosslink the unsaturated double bond in the rubber within the range of 0.1 to 25 parts by weight with respect to -50 parts by weight. If the blending ratio is too high and the SiH group becomes excessive, hydrogen gas is generated due to thermal decomposition in the subsequent steps to cause molding troubles or voids, which impair the toughness. Unless the compounding ratio is low and the degree of crosslinking of unsaturated double bonds is sufficiently high, no improvement in toughness is observed. The hydrosilylation catalyst (d) is used in a proportion necessary for completing the crosslinking reaction within the range of thermal history of the resin composition when the constituent raw materials of the present invention are melt-kneaded by an extruder or other equipment. Although it is compounded, it is effective to premix it in the liquid rubber in advance.

The diene liquid rubber (b) having a functional group used as the raw material of the present invention has a melting point of the novolac type phenolic resin (a) of 0.001 to 500 Pa · Sec.
It is necessary to show the Brookfield viscosity of
When the viscosity of the novolac type phenol resin (a) at the melting point is lower than 0.001 Pa · Sec, the rubber component is separated from the resin, and homogeneous crosslinked particles cannot be obtained. On the other hand, when it exceeds 500 Pa · Sec, it is not easy to disperse the rubber component, and coarse particles are generated.

The diene liquid rubber (b) having a functional group used as a raw material of the present invention is a hydroxyl group, an epoxy group,
N-methylol group, amino group, carboxyl group, or
Although it has an acid anhydride group, these functional groups lower the interfacial tension between the crosslinked rubber and the resin, and make the dispersed particle size of the rubber finer. The dispersion state of the rubber particles whose interface is controlled by the chemical affinity or reaction between both components of the novolac type phenol resin (a) and the diene liquid rubber (b) having a functional group cross-linked is such that the rubber particles are aggregated. Not in condition and 10μ
The particle size is m or less, preferably 1 μ or less.

The toughness of the novolak type phenolic resin (a), which is a sea component, is improved by the fact that not only the rubber component dispersed in a microscopic state works effectively for stress absorption, but also the rubber component originally tough is present at the interface. Affinity at the molecular level,
Alternatively, it is because they are firmly bonded by a chemical reaction. Next, regarding the degree of cross-linking, the degree of cross-linking in the present invention means that 1 g of the modified novolac type phenol resin (phenol resin composition) is refluxed for 10 hours with a Soxhlet extractor using boiling xylene to remove the residue. Retained particle size 1μ
After filtering using a filter paper of m, the ratio of (dry weight of insoluble matter remaining on the filter paper) / (weight of unsaturated double bond group-containing rubber component contained in 1 g of modified phenolic resin + weight of crosslinking agent) was determined. It can be calculated by multiplying by 100. It is preferable to crosslink so that this value is 50% or more, preferably 70% or more.

[0017]

BEST MODE FOR CARRYING OUT THE INVENTION The hydrosilylation catalyst (d) is previously dispersed in the diene liquid rubber (b) having a functional group, and then melt-kneaded with the novolac type phenol resin (a). Since the diene liquid rubber (b) having a functional group is uncrosslinked at this point, it can be finely dispersed in the novolac type phenolic resin (a), and then the finely dispersed uncrosslinked functional group is continuously added. Novolac type phenolic resin (a) containing diene liquid rubber particles (b) having
When the organosilicone-based crosslinking agent (c) is added to and kneaded, the functionalized diene-based liquid rubber particles (b) are crosslinked and fixed in a finely dispersed state. Here, the diene liquid rubber particles (b) having a functional group have a functional group selected from a hydroxyl group, an epoxy group, an N-methylol group, an amino group, a carboxyl group, or an acid anhydride group. When it has an epoxy group, the epoxy group of the crosslinked rubber particles reacts with the hydroxyl group of the phenol resin,
As a result, it is possible to realize a tough phenol resin composition in which the crosslinked rubber particles are stably finely dispersed. Hereinafter, the present invention will be described with reference to examples, but this is merely an example and the present invention is not limited thereto.

[0018]

【Example】

Example 1 Epoxidized polybutadiene: E-1500-8.0 (manufactured by Nippon Petrochemical Co., Ltd., [Brookfield viscosity at 90 ° C. 6 Pa · Sec]) 40 parts by weight was mixed with an organic silico cone-based crosslinking agent. Chloroplatinic acid (H ₂ PtCl ₂ · 6H ₂ O) as a crosslinking catalyst
0.25 parts by weight of the novolak type phenol resin (Sumitomo Dures Co., Ltd. Sumilite Resin R PR-5
After sufficiently blending with 60 parts by weight of 1470 (melting point 90 ° C.), 25 parts by weight of diphenylsilane (TSL8224 manufactured by Toshiba Silicone Co., Ltd.) as a cross-linking agent is added and blended, and melt-kneaded at 100 to 130 ° C. using a pressure kneader. Then, a dynamically vulcanized modified phenolic resin composition was obtained. The modified phenolic resin composition thus obtained was refluxed with a Soxhlet extractor using boiling xylene, and the degree of crosslinking and the degree of crosslinking were 91%. Also,
The resin composition was embedded with Epicoat 828, and the average diameter of the crosslinked particles observed by an electron microscope was 1.8 μm.

Example 2 Hydroxypolybutadiene: Poly bd R-45
5% to 100 parts by weight of HT (Idemitsu Petrochemical Co., Ltd. [Brookfield viscosity at 90 ° C. 0.026 Pa · Sec])
Hydrogenation was carried out using 5 parts by weight of palladium-alumina powder as a catalyst to prepare a partially hydrogenated liquid polybutadiene having a hydrogenation rate of 70%. 9 of this partially hydrogenated hydroxypolybutadiene
The Brookfield viscosity at 0 ° C. was 450 Pa · Sec. Then, 45 parts by weight of this partially hydrogenated liquid hydroxypolybutadiene was mixed with 0.30 part by weight of chloroplatinic acid (H ₂ PtCl ₂ .6H ₂ O) as a crosslinking catalyst for a silicone-based crosslinking agent, and a novolac-type phenol resin (Sumitomo Dures Co., Ltd.) was added. Sumilite Resin R PR-51470, melting point 90 ° C.) 55
After thoroughly blending with parts by weight, diphenylsilane (TSL8224 manufactured by Toshiba Silicone Co., Ltd.) 2 as a crosslinking agent
Using a pressure kneader while adding and blending 5 parts by weight, 1
Melt kneading at 20 to 150 ° C. to obtain a dynamically vulcanized modified phenolic resin composition. The modified phenolic resin composition thus obtained was subjected to reflux with a Soxhlet extractor using boiling xylene to obtain a degree of crosslinking of 9
It was 6%. Further, this resin composition is treated with Epicoat 82.
The average diameter of the crosslinked particles embedded with No. 8 and observed by an electron microscope was 2.2 μm.

Example 3 Hydroxypolychloroprene: LCR FH-050
(Electrochemical Co., Ltd. [Brookfield viscosity at 90 ° C. 0.035 Pa · Sec]) 100 parts by weight was hydrogenated with 5 parts by weight of 5% palladium-alumina powder as a catalyst,
A partially hydrogenated liquid polychloroprene having a hydrogenation rate of 50% was produced. 90 ℃ of this partially hydrogenated hydroxypolychloroprene
Brookfield viscosity at 350 Pa.Sec.
Then, this partially hydrogenated liquid hydroxypolychloroprene 1
0 parts by weight of 0.05 parts by weight of chloroplatinic acid (H ₂ PtCl ₂ · 6H ₂ O) was added as a crosslinking catalyst for the silicone-based crosslinking agent, and a novolac-type phenol resin (Sumilite Resin R manufactured by Sumitomo Dures Co., Ltd.) was added. PR-51470 (melting point 90 ° C.) 90 parts by weight was thoroughly blended, and then diphenylsilane (TSL8224 manufactured by Toshiba Silicone Co., Ltd.) 10 was used as a crosslinking agent.
Using a pressure kneader while adding and blending parts by weight, 12
Melt kneading at 0 to 150 ° C. to obtain a dynamically vulcanized modified phenolic resin composition. The modified phenolic resin composition thus obtained was subjected to reflux with a Soxhlet extractor using boiling xylene to obtain a crosslinking degree of 88.
%Met. In addition, this resin composition is treated with Epicoat 828.
The average diameter of the crosslinked particles, which were embedded by using a microscope and observed by an electron microscope, was 0.6 μm.

Example 4 Hydroxypolybutadiene: Poly bd R-45
Chloroplatinic acid (H ₂ Pt) was added to 20 parts by weight of HT (manufactured by Idemitsu Petrochemical Co., Ltd. [Brookfield viscosity at 90 ° C. 0.026 Pa · Sec]) as a cross-linking catalyst for the organic silicone cross-linking agent.
Cl ₂ .6H ₂ O) 0.05 part by weight, and is a novolac type phenol resin (Sumitomo Durezu Co., Ltd. Sumirite Resin R
PR-51470 (Melting point: 90 ° C.) After thoroughly blending with 80 parts by weight, 1,3,5,7-tetramethylcyclotetrasiloxane (Toray Dow Corning
While adding and blending 5.0 parts by weight of Silicone Co., Ltd., the discharge resin temperature is 130 to 15 using a biaxial kneader.
A modified phenolic resin A was obtained by melt-kneading at a temperature of 0 ° C. and extrusion vulcanization by extrusion. 40 parts by weight of the modified phenolic resin A thus obtained, 7 parts by weight of hexamethylenetetramine as a curing agent, and 53 parts by weight of glass fiber as a reinforcing material were blended and roll-kneaded to obtain a molding material. Thereafter, molding was performed under the condition of 175 ° C. for 3 minutes, the moldability was evaluated, and the obtained test pieces were evaluated for bending strength and Charpy impact strength. Table 1 shows the evaluation results.

Example 5 Epoxidized polybutadiene: E-1500-8.0 (manufactured by Nippon Petrochemical Co., Ltd., [Brookfield viscosity 6 Pa · Sec at 90 ° C.]) 20 parts by weight, and an organic silicone crosslinker Chloroplatinic acid (H ₂ PtCl ₂ · 6H ₂ O) as a crosslinking catalyst for the agent.
05 parts by weight of novolac type phenol resin (Sumitomo Dures Co., Ltd. Sumilite Resin RPR-5147)
After thoroughly blending with 80 parts by weight of melting point 90 ° C.) 1,3,5,7-tetramethylcyclotetrasiloxane as a cross-linking agent (Toray Dow Corning Silicone Co., Ltd.)
(Manufactured by Mitsui Chemicals Co., Ltd.), 5.0 parts by weight was added and blended, and melt-kneaded using a twin-screw kneader under conditions such that the resin temperature was 130 to 150 ° C. and dynamically vulcanized to obtain a modified phenol resin B . 40 parts by weight of the modified phenolic resin B thus obtained, 7 parts by weight of hexamethylenetetramine as a curing agent, and 53 parts by weight of glass fiber as a reinforcing material were mixed and roll-kneaded to obtain a molding material. Then 175 ℃,
Molding was performed under the condition of 3 minutes to evaluate the moldability and the bending strength and the Charpy impact strength of the obtained test piece. Table 1 shows the evaluation results.

Example 6 Carboxylic Acid Modified Polyisoprene: Claprene LIR41
0 ([Kuraray Co., Ltd., Brookfield viscosity at 90 ° C., 2 Pa · Sec]) in 20 parts by weight of chloroplatinic acid (H ₂ PtCl ₂ .6H ₂ O) as a crosslinking catalyst for an organic silicone crosslinking agent. 0
5 parts by weight of novolak type phenol resin (Sumitomo Durez Co., Ltd. Sumirite Resin RPR-51470)
After sufficiently blending with 80 parts by weight of melting point of 90 ° C., 1,3,5,7-tetramethylcyclotetrasiloxane as a cross-linking agent (Toray Dow Corning Silicone Co., Ltd.)
5.0 parts by weight was added and blended, and melt-kneaded with a pressure feeder under conditions such that the kneading resin temperature was 150 ° C. or higher to obtain a dynamically vulcanized modified phenol resin C. 40 parts by weight of the modified phenolic resin C thus obtained, 7 parts by weight of hexamethylenetetramine as a curing agent, and 53 parts by weight of glass fiber as a reinforcing material were mixed and roll-kneaded to obtain a molding material. Thereafter, molding was performed under the condition of 175 ° C. for 3 minutes, the moldability was evaluated, and the obtained test pieces were evaluated for bending strength and Charpy impact strength. Table 1 shows the evaluation results.

Comparative Example 1 Novolak type phenolic resin (Sumilite Resin R PR-5 manufactured by Sumitomo Dures Co., Ltd.)
1470) 40 parts by weight, 7 parts by weight of hexamethylenetetramine as a curing agent, and 53 parts by weight of glass fiber as a reinforcing material were mixed, roll-kneaded in the same manner as in Example 4, and the characteristics were evaluated after molding. Table 2 shows the evaluation results.

Comparative Example 2 Unmodified polyisoprene: Kuraprene LIR50 [Kuraray Co., Ltd., Brookfield viscosity at 90 ° C. 1 Pa · Sec]
Chloroplatinic acid (H ₂ PtCl ₂ .6H ₂ O) was added to 20 parts by weight as a cross-linking catalyst for the organosilicone cross-linking agent as in Example 4.
0.05 parts by weight of novolak type phenol resin (Sumitomo Durezu Co., Ltd. Sumilite Resin R PR-5) is blended.
After sufficiently blending with 80 parts by weight of 1470 (melting point 90 ° C.), 5.0 parts by weight of 1,3,5,7-tetramethylcyclotetrasiloxane (manufactured by Toray Dow Corning Silicone Co., Ltd.) is added as a cross-linking agent. Then, the mixture was melt-kneaded by a pressure feeder under conditions such that the kneading resin temperature was 150 ° C. or higher, and pelletized to obtain a modified phenol resin D. 40 parts by weight of the modified phenolic resin D thus obtained, 7 parts by weight of hexamethylenetetramine as a curing agent and 53 parts by weight of glass fiber as a reinforcing material were blended, roll-kneaded in the same manner as in Example 1, and then molded. The characteristics were evaluated. Table 1 shows the evaluation results.

Comparative Example 3 Novolak type phenolic resin (Sumilite Resin R PR-5 manufactured by Sumitomo Dures Co., Ltd.)
1470 (melting point 90 ° C.) 80 parts by weight and carboxyl group-modified liquid acrylonitrile butadiene copolymer: HYCA
R CTBN1300 × 13 (manufactured by Ube Industries, Ltd. [90
(Brookfield viscosity at 10 ° C., 10 Pa · Sec]) 20 parts by weight were thoroughly blended, and then the resin temperature was adjusted to 8
A resin composition melt-kneaded under the condition of 0 to 120 ° C. is pelletized to obtain a modified phenol resin E.
I got Modified phenol resin E thus obtained
40 parts by weight, hexamethylenetetramine 7 as a curing agent
By weight, and 53 parts by weight of glass fiber as a reinforcing material were mixed, roll kneading was carried out in the same manner as in Example 4, and after molding, the characteristics thereof were evaluated. Table 1 shows the evaluation results.

[0027]

[Table 1]

* 1 Moldability: The surface condition of the test piece after molding and the filling state of the molding material into the test piece mold were visually observed and evaluated. ◯: Appearance of test piece: Good. Filling state in the mold: Good Δ: Appearance of test piece: somewhat uneven. Filling state into mold: last minute ×: Appearance of test piece: unevenness. Filling state in mold: occurrence of non-filling * 2 Bending strength: Measured according to JIS K6911. * 3 Charpy impact strength: measured according to JIS K6911.

[0029]

As is apparent from Table 1, when the phenol resin composition of the present invention is used as a molding material, a laminate, or a curing agent for epoxy resin, a molding having tough properties can be obtained.

Claims (3)

[Claims] 1. A novolak type phenol resin (a), a diene liquid rubber (b) having a functional group, an organic silicone cross-linking agent (c) and a hydrosilylation catalyst (d) are melt-kneaded. A tough phenol resin composition. 2. A diene liquid rubber (b) having a functional group.
Is a polymer composed of at least one selected from polybutadiene, polyisoprene, polychloroprene, butadiene-isoprene copolymer, butadiene-styrene copolymer, acrylonitrile-butadiene copolymer, or natural rubber, or a part thereof. The tough phenol resin composition according to claim 1, which is a hydrogenated product and has a hydroxyl group, an epoxy group, an N-methylol group, an amino group, a carboxyl group, or an acid anhydride group. 3. The toughness according to claim 1 or 2, wherein the Brookfield viscosity of the functional group-containing diene liquid rubber (b) at the melting point of the novolac type phenol resin (a) is 0.001 to 500 Pa · Sec. Phenolic resin composition.