JPH0733419B2 - Curable resin composition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention mainly relates to various building materials molded by casting,
For example, the present invention relates to a curable resin composition used for producing a marble bath, a vanity, a kitchen counter, a table top, and the like.

[Conventional technology and problems]

In recent years, when molding a large-sized molded article such as a bathtub, the appearance of a high-grade marble tone has been given by casting to form a field of bathtubs. Generally, polyester resin,
Vinyl ester resin is used.

However, the problem with using these resins is that if the resin composition is selected so as to satisfy the hot water resistance, which is an essential physical property for bathtubs, it is necessary to use a resin that is inevitably hard and has relatively high reactivity. That is, there is a high risk of cracking during molding or with the passage of time.

It is well known that a polymer is used in combination from the viewpoint of reducing the shrinkage ratio in order to prevent cracking, but in the case of products with a lifelike appearance such as artificial marble, it is possible to use polymer precipitation during curing. Cloudiness tends to impair transparency and significantly impair its commercial value.

[Means for Solving the Problems]

That is, the present invention provides (1) 0.1 to 50 mol% of a radical-polymerizable unsaturated compound having an acid anhydride group, and monomers 99.9 that radically copolymerize with the unsaturated compound.
A polymer having an acid anhydride group composed of ˜50 mol% and having a molecular weight of 10,000 or more and 100,000 or less, and (2) two or more hydroxyl groups (meta ) A vinyl ester resin having an acryloyl group, and a curable resin composition.

Thus, in the present invention, (1) 0.1 to 50 mol% of a radical-polymerizable unsaturated compound having an acid anhydride group, and monomers 99.9 that radical-copolymerize with the unsaturated compound
A polymer having an acid anhydride group composed of ˜50 mol% and having a molecular weight of 10,000 or more and 100,000 or less, and (2) two or more hydroxyl groups (meta ) Acryloyl group-containing vinyl ester resin is used in combination, and during the casting process, the hydroxyl group of the vinyl ester resin and the acid anhydride group of the polymer undergo a ring-opening addition reaction to give a side chain of the thermoplastic polymer. It is based on the fact that it is converted into a form containing a (meth) acryloyl group, resulting in a thermosetting type, which is different from a mere blend of a thermoplastic polymer and a vinyl ester resin.

The polymer having a molecular weight of 10,000 or more and 100,000 or less in (1) above is
Substantially one or more acid anhydrides are contained in the molecule. Here, the reason is substantially explained as follows, for example.

If we look at the copolymerized polymer of styrene and maleic anhydride, if the composition is 99 moles of styrene and 1 mole of maleic anhydride, this polymer is one acid anhydride if the molecular weight is 10,000 or more. It becomes a calculation with a group.

Similarly, if the molecular weight is 100,000, the molar ratio of maleic anhydride should be 0.1 mol%. From a practical point of view, the molecular weight of the polymer containing an acid anhydride group is preferably 10,000 or more and 100,000 or less. Therefore, the ratio of the unsaturated acid anhydride used is 0.1 mol% or more and 50 mol% or less, preferably 1 mol% or more and 30 mol or less. % Or less. The radical-polymerizable unsaturated compound having an acid anhydride group is most typically maleic anhydride, which is sufficient for the purpose of the present invention. In addition to this, itaconic anhydride can be used although the cost is high.

Monomers for radical copolymerization with these unsaturated acid anhydrides to form a polymer having an acid anhydride group,
There is no particular limitation if copolymerization is possible. For example, there are the following types. Styrene, vinyltoluene, chlorostyrene, methyl methacrylate and methacrylic acid esters, acrylic acid esters, acrylonitrile, methacrylonitrile, vinyl acetate, vinyl chloride, isobutylene, ethylene. Further, it is of course possible to use these in combination.

Artificial marble, especially styrene is useful when boiling resistance is required as in bathtubs, and when boiling resistance is not required as in vanities, a type such as combination with methyl methacrylate or styrene is recommended. Mainly used.

The polymerization method is carried out by the existing methods, but the thermal polymerization method in an inert gas stream without using a catalyst is the most convenient. It is not necessary to complete the polymerization, and it is convenient to leave the monomer and use it as a monomer solution.

As one aspect of polymerization, for example, maleic anhydride is also added to a thermoplastic polymer by a grafting method, which is not necessarily unavailable, but it has a particular advantage as compared with the polymerization method. I don't think there is.

The vinyl ester resin used in the present invention is generally synthesized by the reaction of (meth) acrylic acid and an epoxy resin.

It can also be synthesized from polyhydric phenol or novolac and glycidyl methacrylate, but the cost of glycidyl methacrylate is high, and industrial merits are reduced.

During the reaction, a catalyst such as a Lewis base, a quaternary ammonium salt, a quaternary phosphonium salt, a quaternary sulfonium salt or sodium methylate is used.

These catalysts are also useful as reaction catalysts when reacting a polymer having an acid anhydride group with a vinyl ester resin.

It is not necessary to particularly limit the epoxy resin constituting the vinyl ester resin, but in general, bisphenol A diglycidyl ether, bisphenol F diglycidyl ether, and bisphenol S are taken into consideration in terms of cost and physical properties of the cured resin.
Examples thereof include diglycidyl ether (all of which include polymerization homologues), and cycloaliphatic diglycidyl compounds.

Regarding the mixing ratio of the polymer having an acid anhydride group and the vinyl ester resin, the polymer can be used in the range of 95 to 5% by weight (the weight is omitted hereinafter) and the vinyl ester resin in the range of 5 to 95%. Is 80 to 20% polymer and 20 to 80% vinyl ester resin.

Curing of the mixed resin is carried out by the competitive reaction between the polymerization of the (meth) acryloyl group of the vinyl ester resin and the copolymerization with the monomer, and the addition reaction between the acid anhydride group in the polymer and the hydroxyl group in the vinyl ester resin. Seen to be done.

Therefore, the use of a radical generating catalyst and a catalyst for ring-opening addition reaction of an acid anhydride group and a hydroxyl group (for example, an alkali metal alcoholate or a Lewis base) as a curing catalyst results in a molded article having a good appearance. Needed to get.

Advantageous Effects of Invention According to the present invention, cracks are prevented from being generated when a large-sized molded product is manufactured by casting, and the molded product also has an advantage that a semi-transparent and high-grade marble-like product can be easily obtained.

The resin composition according to the present invention is mild in heat generation during curing and hardly cracks, and the cured resin is hard but has elongation and exhibits toughness. In addition, it has good boiling resistance and shows no whitening or yellowing due to boiling.

The curable composition according to the present invention can, of course, be used in combination with a filler, a reinforcing material, a coloring agent, a defoaming agent, a release agent, polymers, etc., if necessary.

Next, the present invention will be further described with reference to examples. In the examples, “parts” means “parts by weight” unless otherwise specified.

Example 1 Synthesis of Polymer (A) Having Acid Anhydride Group 967 g of styrene was weighed in a 2 separable flask equipped with a stirrer, a heating dropping funnel, a reflux condenser, and a thermometer with a gas introduction tube, and a nitrogen gas flow was obtained. 69 g of molten maleic anhydride were added dropwise at 120 ° C. to 125 ° C. over 4 hours. During this period, 2.5 g of lauryl mercaptan was added every hour by 2.5 g.

After the addition of maleic anhydride was completed, the temperature was kept at the same temperature for 1 hour, and it was confirmed that free maleic anhydride had disappeared with dimethylaniline tephate, and 0.1 g of hydroquinone was added to terminate the polymerization. Number average molecular weight of about 38,000. The polymerization rate reaches about 52%, the molar ratio of styrene to maleic anhydride in the copolymer is about 85:15, and the Hazen color number is 2
A styrene-maleic anhydride copolymer (A) having 0 and a viscosity of 11.4 poise was obtained.

Synthesis of vinyl ester resin (B) In a one-separable flask equipped with a stirrer, a reflux condenser, and a thermometer, 370 epoxy resins with an epoxy equivalent of 181 are placed.
g, acrylic acid 144g, sodium methylate (solid content)
1.5 g, triphenyl phosphite 2.5 g and hydroquinone monomethyl ether 0.25 g were charged and reacted at 120 to 125 ° C. for 4 hours. The acid value was 5.9. 220g styrene
The vinyl ester resin (B) has a Hazen color number of 15
It was obtained at 0 and a viscosity of 5.9 poise.

Preparation of casting plate On a 30 cm x 30 cm glass plate coated with a release agent, 100 parts of polyester resin "Rigolac G-400" manufactured by Showa High Polymer Co., Ltd. as a gel coat resin, 3 parts of Erosil and silicone type Foaming agent 10 ppm, 2 parts of Dalocure # 1173 from Merck Co., Ltd. as a photoinitiator, and 1 part of an organic peroxide of Kayaku Nouri Co., Ltd. Perkadox # 16 was used.
After coating with a bar coater to a thickness of 0.5 m / m, 20 cm under a sun lamp was irradiated for 15 minutes to cure.

Next, place a gel coat layer (glass plate) on one side and a glass mat white FRP plate with a thickness of 1.5 m / m on the other side. 250 parts of polymer (A) and vinyl ester resin (B ) 250 parts, sodium methylate (solid content) 1.5
Parts, 800 parts of glass frit and 7.5 parts of Perkadox # 16 were poured and then heated at 60 ° C. for 2 hours and 70 ° C. for 3 hours to cure. A slightly turbid, semi-transparent white cast plate was obtained.

The maximum exothermic temperature during casting was 98 ° C.

Hot water contact test Cut the casting plate into the desired size and put the gel coat surface on it.
The immersion test was performed by touching the hot water at 95 ° C.

As a comparative example, a polyester resin prepared by mixing 5.5 mol of propylene glycol, 5.3 mol of neopentyl glycol, 5 mol of isophthalic acid, and 5 mol of maleic anhydride with an unsaturated alkyd having an acid value of 29.1 as a 45% styrene solution was used in the same formulation. Glass frit and Perkadox # 16 were mixed so as to obtain a casting plate having a similar photo-curing gel coat layer. The maximum exothermic temperature in this case is 139 ℃
Then, a crack was generated at the end.

The results show that, as shown in Table 1, the resin composition of the present invention has excellent performance.

Example 2 Synthesis of Polymer (C) Having Acid Anhydride Group In a one-separable flask equipped with a stirrer, a reflux condenser, a thermometer, and a gas introduction tube, 84 g of itaconic anhydride, 425 g of methyl methacrylate, and 5 g of lauryl mercaptan were charged. The mixture was heated for 6 hours under reflux of methyl methacrylate in a nitrogen gas stream. Since it became difficult to stir, 300 g of methyl methacrylate and 0.7 g of monomethoxyhydroquinone were added.
The obtained polymer (C) having an acid anhydride group (≈52% methyl methacrylate solution) had a Hazen color number of 20 and a viscosity of 13.1
It was a poise (polymer number average molecular weight of about 30,000).

Synthesis of vinyl ester resin (D) In a one-separable flask equipped with a stirrer, a reflux condenser, and a thermometer, Union Carbite's ERL-4221 (epoxy equivalent 270) was used as a cycloaliphatic epoxy resin.
270 g, 174 g of methacrylic acid, 2 g of tetrabutylphosphonium bromide (trade name: TBP-BB) manufactured by Hokuko Kagaku Co., Ltd. as a quaternary phosphonium salt catalyst, and 0.2 g of hydroquinone monomethyl ether were charged and reacted at 130 to 135 ° C. for 3 hours. . The acid value was about 9. Methyl methacrylate 25 at 90 ° C
By adding 6 g, a vinyl ester resin (D) (≈36.5% methyl methacrylate solution) was obtained with a Hazen color number of 150 and a viscosity of 3.9 poise.

Manufacturing and properties of cast products 700 parts of polymer (C) and 3 parts of vinyl ester resin (D)
00 parts, aluminum hydroxide (Showa Denko's Heidilite H
-32% 70%, H-310 30% mixed type) 1500 parts, benzoyl peroxide 20 parts are uniformly mixed and cast to have a thickness of 12 mm between 300 mm x 300 mm mold release agent coated glass plates. After doing
It was cured at 80 ° C. for 12 hours and at 120 ° C. for 4 hours to obtain a milky white artificial marble plate having a slightly transparent feeling.

The physical properties of this cast plate were as shown in Table 2.

Example 3 Synthesis of Polymer (E) Having Acid Anhydride Group In a one-separable flask equipped with a stirrer, a reflux condenser, a gas introduction tube, and a thermometer, 250 g of styrene and 20 g of methacrylonitrile were charged, and the temperature was set to 130 in a nitrogen stream. ~ 135
At 0 ° C., 30 g of molten maleic anhydride was added dropwise over about 3 hours.

At the end of the dropping, the viscosity increased and the stirring became a little difficult, so 52 g of styrene was added, the temperature was lowered to 120 ° C., and the polymerization was further continued for 2 hours.

As a result of gas chromatographic analysis, the residual amount of methacrylonitrile was estimated to be 0.3% or less.

Hydroquinone (0.1 g) and styrene (104 g) were added, and a polymer (E) having an acid anhydride group was obtained with a Hazen color number of 150 and a viscosity of 9.1 poise.

Synthesis of vinyl ester resin (F) In a one-separable flask equipped with a stirrer, a reflux condenser, and a thermometer, 360 g of DEN-431 (epoxy equivalent 176, about 2.1 nuclide) of Dow Chemical Co. as a novolac type epoxy resin, Methacrylic acid 172g, dimethylamino ethanol 2.5g, hydroquinone 0.25g were charged, 130-135
The reaction was carried out at ℃ for 4 hours. The acid value was 4.6. 230 g of styrene was added to this to obtain a vinyl ester resin (F) with a Gardner color number of 3 and a viscosity of 8.6 poise.

Manufacturing and physical properties of FRP 40 parts of polymer (E), 60 parts of vinyl ester resin (F),
7 parts of powdered polyethylene, 150 parts of calcium carbonate, 30 parts of 1/4 glass fiber, 5 parts of zinc stearate, 2 parts of t-butyl perbenzoate, 3 parts of surface-treated carbon black are kneaded with a kneader to give a soft putty-like molding material. And 40
By aging at 0 ° C. overnight, the viscosity increased and the surface became non-tacky.

The test piece could be molded under the molding conditions of 140 to 145 ° C and 100 kg / cm ² . The properties of the molded products are shown in Table 3.

For reference, when the entire amount of the vinyl ester resin (F) was used instead of the polymer (E), the viscosity did not increase, and it remained as a very soft putty. Further, in this type of molded product, color unevenness remarkably occurred, and since the material was soft, molding was difficult and a satisfactory molded product could not be obtained.

EFFECTS OF THE INVENTION Since the present invention is configured as described above, the resin composition exhibits mild heat generation during curing and is unlikely to crack, and the cured resin is hard but has elongation and exhibits toughness. In addition, it has good boiling resistance and shows no whitening or yellowing due to boiling. Further, there is an advantage that cracks are prevented from being generated when a large-sized molded product is manufactured by casting, and that the molded product has a semi-transparent appearance and can easily obtain a high-grade marble-like product.

Claims (1)

[Claims] (1) 0.1-50 mol% of a radical-polymerizable unsaturated compound having an acid anhydride group, and monomers 99.9 radical-copolymerizable with this unsaturated compound
A polymer having an acid anhydride group composed of ˜50 mol% and having a molecular weight of 10,000 or more and 100,000 or less, and (2) two or more hydroxyl groups (meta ) A curable resin composition, which is used in combination with a vinyl ester resin having an acryloyl group.