JPH07278424A - Thermoplastic resin composition - Google Patents

Abstract

PURPOSE:To obtain the subject composition which can give a molding excellent transparent appearance, quality appearance and weighty appearance. CONSTITUTION:This resin composition is obtained by mixing 100 pts.wt. thermosetting resin selected from the group consisting of an unsaturated polyester resin, a vinyl ester resin, an unsaturated acrylic resin and an epoxy resin with 200-500 pts.wt. barium sulfate having a mean particle diameter of primary particles of 1mum or below and 50-300 pts.wt. hydrated alumina particles having a mean particle diameter of 60mum or below.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a thermosetting resin composition. More specifically, the present invention is
The present invention relates to a thermosetting resin composition capable of obtaining a molded product excellent in texture and weight.

[0002]

2. Description of the Related Art Conventionally, various plastic molded products have been proposed or produced for the purpose of substituting natural materials. However, in the prior art, although it was enthusiastic about how to make the appearance of the plastic molded product closer to that of the natural material, the texture and the feeling of weight were poor, and the weight increase was disliked. I can't see it.

The inventors of the present invention have conducted research on synthetic materials which replace inorganic natural materials. However, if only the appearance is imitated, the material lacks a feeling of weight and does not look like natural materials. As a result of repeated studies on the development of texture and high-grade feeling, thermosetting resins such as radical curing resins such as polyester resins and vinyl ester resins or curing by ring-opening reaction found in epoxy resins were used. When I did it, I knew that if it didn't have the same specific gravity of 2.3 to 3.3 as that of natural stone, it would still lack texture and weight.

However, a filler having a high specific gravity, such as titanium white (= titanium sulfide) or zirconium oxide, or barium sulfate which is usually commercially available, is added alone or in a mixture to simply increase the specific gravity of the molded product. In terms of products, it lacked a sense of transparency, lacked a sense of luxury, and had no commercial value.

It is well known that hydrated alumina or glass powder is often used as a filler in an artificial marble using a polyester resin in order to give a transparent feeling. For example, hydrated alumina alone is used. Even if it was added to the limit of mixing, the specific gravity of the molded product was 2.3 or less, and it was also lacking in high-class feeling, that is, texture and weight feeling. It is an object of the present invention to provide a thermosetting resin composition that solves the above-mentioned conventional problems and can provide a molded article excellent in transparency, texture and weight.

[0006]

Means for Solving the Problems As a result of intensive studies, the inventors of the present invention, for example, have a specific gravity of 2.3 to 3, which is equivalent to that of a natural stone material.
As a result of various investigations to obtain a thermosetting resin-based molded product having No. 3, which has transparency, texture and weight, a specific thermosetting resin and a specific filler 2 having specific conditions
It was found that the above object can be achieved only by using seeds, and the present invention could be completed.

That is, the present invention relates to [A] unsaturated polyester resin, vinyl ester resin,
200 to 500 parts by weight of barium sulfate in which [B] (1) primary particles have an average particle size of 1 μm or less, relative to 100 parts by weight of a thermosetting resin selected from the group consisting of unsaturated acrylic resins and epoxy resins, and (2) Hydrated alumina 50 to 50 having an average particle size of 60 μm or less
The present invention provides a thermosetting resin composition containing 300 parts by weight.

Further, the present invention provides the above-mentioned thermosetting resin composition, wherein the average particle size of primary particles of barium sulfate is 0.01 to 1 μm.

The present invention also provides the above-mentioned thermosetting resin composition, wherein the hydrated alumina particles have an average particle size of 0.1 to 60 μm.

Furthermore, the present invention has a specific gravity of 2. obtained by molding using any of the thermosetting resin compositions described above.
A resin molded product of 3 to 3.3 is provided.

The thermosetting resin used in the present invention is
(1) unsaturated polyester resin, vinyl ester resin,
It is a radical curable resin such as unsaturated acrylic resin, or (2) epoxy resin. The unsaturated polyester resin, vinyl ester resin, and unsaturated acrylic resin of (1) may be mixed and used, and the mixing ratio is arbitrary.

(A) The unsaturated polyester resin used in the present invention contains an α, β-unsaturated polybasic acid (or an anhydride thereof) such as maleic anhydride and fumaric acid as one component, and if desired, is anhydrous. Saturated or unsaturated polybasic acids (or their anhydrides) such as phthalic acid, isophthalic acid, terephthalic acid and terephthalic acid dimethyl ester are used in combination with ethylene glycol, propylene glycol, 1,
An unsaturated alkyd obtained by esterification with a polyhydric alcohol such as 4-cyclohexanedimethanol according to a conventional method is dissolved in monomers such as styrene and diallyl phthalate. The unsaturated alkyd obtained by the conventional esterification method usually has a number average molecular weight of less than 3,000. The composition does not need to be particularly limited. Depending on the application, a diallyl phthalate prepolymer or a type in which a polyester having an allyl ester group at the terminal is used in combination with an unsaturated alkyd can also be used.

(B) The vinyl ester resin used in the present invention is also called an epoxy-acrylate, and a resin having an epoxy group as a (meth) acryloyl group is obtained by reacting an epoxy resin with (meth) acrylic acid. It can be used with or without a monomer.
The vinyl ester resin has a number average molecular weight of 500 to 2.0.
It is about 00.

(C) The unsaturated acrylic resin used in the present invention is one having one or more equivalents of radical-curable (meth) acryloyl group in one molecule, other than the above vinyl ester resin, and urethane- Acrylate; so-called acrylic syrup obtained by partial polymerization of methyl methacrylate; polyester acrylate, etc. are included. The number average molecular weight of the unsaturated acrylic resin is 500 to 2,000.
It is of a degree.

(D) The epoxy resin used in the present invention is not particularly specified, but so-called bisphenol A type and novolac type are suitable, and amines are used as the curing agent in the molded article in order to avoid coloring. This is not appropriate, and a system in which an imidazole-based catalyst is used in combination with novolac is desirable. The number average molecular weight of the epoxy resin is 400 to 2,
The number average molecular weight of the novolak type is about 300 to 1,000.

The barium sulfate used in the present invention must have an average primary particle diameter of 1 μm or less. With an average particle size of more than 1 μm, it is difficult to obtain a high-class feeling because of lack of transparency. The average particle diameter of barium sulfate practically used in the present invention is 0.01 to 1 μm, preferably 0.03 to 0.3 μm.

The hydrated alumina used in the present invention needs to have an average particle size of 60 μm or less, and it is desired that the particle size distribution be as wide as possible. If the average particle size of the hydrated alumina exceeds 60 μm, the strength of the molded product tends to be impaired, and the molded product has a rough feeling, which is not preferable. In the present invention, the practical average particle size of hydrated alumina is 0.1 to 60 μm,
It is preferably 1 to 30 μm.

The mixing ratio of barium sulfate and hydrated alumina varies depending on the intended specific gravity, but the specific gravity is 2.3 to 3.
If 3 is targeted, barium sulfate is 200 to 500 parts by weight, and hydrated alumina is 50 to 300 parts by weight with respect to 100 parts by weight of the thermosetting resin. Also, the specific gravity is 2.5
For the purpose of up to 3.0, the above thermosetting resin 10
With respect to 0 parts by weight, barium sulfate is 300 to 500 parts by weight, and hydrated alumina is 100 to 300 parts by weight. In addition,
When an epoxy resin is used as the thermosetting resin and phenol novolac is used as the curing agent, barium sulfate and hydrated alumina can be blended with 100 parts by weight of the total amount thereof.

In the composition of the present invention, a curing agent and a release agent are usually used in combination, and a coloring agent may be used if necessary.
Further, a reinforcing material and a thermoplastic polymer can also be used together according to the required performance. The mixing of the thermosetting resin, barium sulfate and hydrated alumina, and the above-mentioned various additives is not particularly limited, but is usually performed by a roll or a kneader. When molding the composition of the present invention, a desired molding can be obtained by using a desired molding method such as compression molding, transfer molding, injection molding or the like.

[0020]

The present invention makes it possible to obtain a molded product having a high specific gravity by using a specific thermosetting resin, and further by using barium sulfate and hydrated alumina having specific conditions, whereby a texture can be obtained. It is possible to impart a high-grade feeling such as a feeling of weight. The reason why the thermosetting resin is used in the present invention is that a large amount of the filler is used in combination, the molecular weight is small and it is easy to knead, and it can be hardened by heating to impart physical properties to the thermoplastic polymer. The combined use of such a large amount of filler is
This is extremely difficult in terms of kneading or molding. Molded articles produced from the resin composition of the present invention are stamp materials,
It is usefully used as a base for ornaments, artificial marble, and various building materials.

[0021]

EXAMPLES The present invention will be described below with reference to examples. The flexural strength and flexural modulus in the examples are measured according to JIS K6.
It was measured according to 911.

Example 1 Synthesis of unsaturated polyester resin (A) In a 1-liter separable flask equipped with a stirrer, a fractionating condenser, a thermometer, and a gas introduction tube, 70 g of ethylene glycol and 150 of 1,4-cyclohexanedimethanol.
g, isophthalic acid 224g, and in a nitrogen gas stream, 2
The acid value is 29.1 by heating to 00-205 ℃ to esterify.
After that, 69 g of maleic anhydride and 0.1 g of phosphorous acid were added, and after esterification to an acid value of 34.7, the temperature was lowered to 140 ° C. and air was replaced with hydroquinone 0.0
Add 8g, then 370g of styrene, dissolve evenly,
An unsaturated polyester resin (A) having a Hazen color number of 70 and a viscosity of 9.4 poise was obtained. The number average molecular weight of the unsaturated alkyd was 2,100.

A molding material [I] was produced with the following composition. Unsaturated polyester resin (A) 100 parts by weight Barium sulfate (BARIFINE BF-10 manufactured by Sakai Chemical Industry Co., Ltd., primary particle size 0.06 μm) 380 parts by weight Hydrated alumina (Hijilite H-31 manufactured by Showa Denko KK, average particle size) 17 μm) 160 parts by weight Dicumyl peroxide 2 parts by weight Zinc stearate 5 parts by weight Magnesia 1 part by weight

After kneading the above mixture with a kneader, one week,
It was cured in a closed container at 40 ° C. A hard putty-like molding material was obtained. A test piece was molded at a mold temperature of 150 ° C. and a pressure of 100 kg / cm ² . The specific gravity of the obtained test piece is 2.7, the bending strength is 4.6 kg / mm ² , the bending elastic modulus is 1.6.
It had a transparency of 10 kg / mm ² , and had a slightly pale green-yellow color.

Example 2 Synthesis of unsaturated polyester (B) A 1-liter separable flask equipped with a stirrer, a fractionating condenser, a thermometer, and a gas introduction tube was charged with 78 g of propylene glycol and 398 g of isophthalic acid, and a nitrogen gas stream was introduced. Acid value of 2 by esterification by heating to 180-190 ℃
After adjusting to 8.9, maleic anhydride 157g, phosphorous acid 0.
24 g was added, and the esterification was continued. Finally, the acid value was 39.1 and the reaction was carried out under reduced pressure of about 20 Torr for 3 hours to give an acid value of 28.6. The temperature was lowered to 140 ° C. and 0.08 g of hydroquinone was added. In addition, it was poured into a metal vat and solidified.
An unsaturated polyester (B) having a light yellowish brown color, a melting point of about 80 ° C. and a number average molecular weight of 2,360 was obtained.

A molding material [II] was produced with the following formulation. Unsaturated polyester (B) 50 parts by weight diallyl phthalate prepolymer (Daiso Dap manufactured by Daiso) 20 parts by weight Terminal allyl group polyester (EA-901B manufactured by Showa Denko KK) 30 parts by weight Barium sulfate (BARIFINE BF- manufactured by Sakai Chemical Industry Co., Ltd.) 20, primary particle diameter 0.03 μm) 400 parts by weight Hydrated alumina (Showa Denko Hijilite H-21, average particle size 25 μm) 100 parts by weight Hydrated alumina (Showa Denko Hijilite H-32, average particle) Diameter 8 μm) 100 parts by weight Dicumyl peroxide 3 parts by weight Zinc stearate 5 parts by weight Grafted carbon black 3 parts by weight

The above compound was roll-kneaded at 110 to 120 ° C. and then roughly crushed to produce a molding material [II]. Mold temperature 1
A test piece was molded at 65 to 170 ° C. and a pressure of 100 kg / cm ² . The specific gravity of the obtained test piece is 2.8,
Bending strength 3.11 kg / mm ² , bending elastic modulus 1,550 kg / m
m ² , a slightly transparent black color, and had an obsidian-like appearance, texture, and weight.

Example 3 Synthesis of vinyl ester resin (C) In a 1 liter separable flask equipped with a stirrer, a reflux condenser, a thermometer, and a gas introduction tube, an epoxy equivalent of 18
3, liquid epoxy resin 370g, methacrylic acid 172g,
Triphenylphosphine (2 g), phosphorous acid (0.2 g) and hydroquinone (0.2 g) were charged, and the mixture was heated to 125-130
After reacting at ℃ for 3 hours, the acid value becomes substantially zero,
A vinyl ester resin (C) was obtained with a Hazen color number of 450 and a viscosity of about 1,500 poises. Next, 90 ℃, 5mmHg
It was dried overnight. The number average molecular weight of the vinyl ester resin (C) was about 500. Subsequently, 400 barium sulfate (BF-1 manufactured by Sakai Chemical Industry Co., Ltd., primary particle size: 0.05 μm) was added.
g, hydrated alumina (Showa Denko Hijilite H-42
M, 100 g of average particle diameter 1.0 μm) and 100 g of another hydrated alumina (Hijilite H-31 manufactured by Showa Denko KK, average particle diameter 17 μm) were charged in a heating kneader, 55-55
Vinyl ester resin (C) 100 while heating to 60 ° C
g was added. When the whole became uniform, 3 g of zinc stearate, 2 g of dicumyl peroxide, 25 g of hexamethylene diisocyanate and 0.2 g of dibutyltin laurate were added, and kneading was continued at a temperature of 70 ° C. When the viscosity was remarkably increased and the mixture became putty-like, it was taken out and cooled to room temperature to obtain a hard solid molding material [III]. Molding material [II
I] was molded into a test piece at a mold temperature of 160 ° C. and a pressure of 150 kg / cm ² for 5 minutes. The obtained test piece had a specific gravity of 2.77, a bending strength of 5.9 kg / mm ² , a transparent feeling, and a slightly greenish ivory color.

Example 4 A novolac type epoxy resin having a number average molecular weight of about 4
20 Asahi Dow DEN-432 200 g, curing agent phenol novolak (Showa High Polymer Co., Ltd., number average molecular weight about 400) 120 g, accelerator 2-methylimidazole 5 g, barium sulfate (reagent grade, average particle size) 0.56
μm: Breakdown 1-2 μm 10.2%, 0.5-1 μm 32.8
%, 0.5 μm or less 48.6%) 1100 g, hydrated alumina (Showa Denko Hijilite H-21, average particle size 25)
μm) 600 g, zinc stearate 15 g, and Hoechst wax E 5 g are kneaded on a roll at 110 to 115 ° C. until a uniform plate shape is obtained, and then cooled and coarsely crushed to obtain a molding material [I
V]. This molding material [IV] is used at a mold temperature of 160-
A test piece was molded at 165 ° C. and a pressure of 100 kg / cm ² . The obtained test piece had a specific gravity of 2.58, a bending strength of 2.9 kg / mm ² , a transparent feeling, and an ivory color.

[0030]

Industrial Applicability According to the present invention, there is provided a thermosetting resin composition capable of obtaining a molded article excellent in transparency, texture and weight.

Claims (4)

[Claims] 1. A thermosetting resin selected from the group consisting of an unsaturated polyester resin, a vinyl ester resin, an unsaturated acrylic resin, and an epoxy resin [A] to 100 parts by weight of a [B] (1) primary particles. 200-500 parts by weight of barium sulfate having an average particle diameter of 1 μm or less, and (2) hydrated alumina 50-having an average particle diameter of 60 μm or less
A thermosetting resin composition comprising 300 parts by weight. 2. The thermosetting resin composition according to claim 1, wherein the primary particles of barium sulfate have an average particle diameter of 0.01 to 1 μm. 3. The average particle size of the particles of hydrated alumina is
The thermosetting resin composition according to claim 1, which has a thickness of 0.1 to 60 μm. 4. A resin molded product having a specific gravity of 2.3 to 3.3, which is obtained by molding using the thermosetting resin composition according to any one of claims 1 to 3.