JPH0780972B2 - Polymerizable composition for resin mold molding and resin mold - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a resin mold for molding FRP products, for example, and a polymerizable composition for molding the resin mold.

[0002]

2. Description of the Related Art Resin molds are widely used in the production of a large number of small quantities of plastic products because they can be manufactured at a lower cost in a shorter construction period than molds. As the resin for resin molding, unsaturated polyester, vinyl ester, epoxy, urethane, silicon, etc. are used, and the resin is a reinforcing material such as glass fiber, metal powder such as aluminum or iron, or aluminum hydroxide or glass. It is molded in combination with a filler such as powder.

[0003]

Although the resin mold can be manufactured in a short construction period, it takes a considerable number of days for all the resins to completely cure, so that a construction period of several weeks is necessary. In order to shorten the number of manufacturing days, measures such as increasing the amount of the curing agent, molding the resin mold thick at once, or heating and heating are usually taken.

However, when the curing reaction of the resin is rapidly progressed in this way, the dimensions may change due to heat shrinkage of the resin,
Cracks and warpage occur. Therefore, it is necessary for a skilled person to slowly mold the resin mold while controlling the heat generation of the resin. That is, in order to satisfy the required characteristics of the mold, it is inevitable that the molding period is extended to some extent.

In view of the above problems, the present invention facilitates a resin mold which is completely hardened in a short time without heating and heating from the outside, has good dimensional accuracy, and is durable and free from cracks and warps. The object is to provide a material that can be molded.

[0006]

The present inventors have found that the cause of cracks, warps and dimensional deviations in conventional resin molds is that the resin used for molding the resin mold is not completely cured. However, it has been found that when such a mold is repeatedly heated and cooled to actually manufacture a molded product, the reaction of the mold resin further proceeds, which causes the above-mentioned fatal problems as a mold. Then, they found that the specific polymerizable composition was completely cured in a few minutes even at room temperature, and completed the present invention.

That is, the present invention provides the reaction of (a) a hydroxyl group of a hydroxyalkyl (meth) acrylate with an isocyanate group of a polyvalent isocyanate having no urethane group and having an isocyanate functionality of more than 2.0. the resulting polyvalent (meth) acrylates bets (hereinafter, simply referred to as unsaturated urethane), (b) methyl methacrylate, a resin comprising a low-profile additive and (d) filler (c) consisting vinyl polymer It is a composition for polymerization for molding.

The composition for polymerization according to the present invention comprises the above components.
(a) unsaturated urethane, (b) methyl methacrylate, (c)
In addition to the low-shrinking agent and (d) filler, (e) unsaturated polyester or vinyl ester resin and / or
(f) General formula:

[Chemical 2] A compound having a plurality of (meth) acrylate groups represented by the formula (wherein R represents a hydrogen atom or a methyl group) and having no urethane group or hydroxyl group may be included. In this case, the amount of unsaturated urethane (a) used is reduced by adding unsaturated polyester or vinyl ester resin (e), and methyl methacrylate is added by adding compound (f).
Cost reduction can be achieved by reducing the amount of (b) used.
Components (e) and (f) also serve as a vehicle for the pigment.

Unsaturated urethanes (a) are prepared by reacting the hydroxyl groups of hydroxyalkyl (meth) acrylates with the isocyanate groups of polyisocyanates which have no urethane groups and which have an isocyanate functionality of greater than 2.0. A polyurethane poly (meth) acrylate resin derived from an alkyl (meth) acrylate.

Hydroxyalkyl (meth) acrylates as unsaturated urethanes (a) contain 2 to 4 carbon atoms in the hydroxylalkyl group. The polyisocyanate having no urethane group is, for example, polymethylene polyphenyl polyisocyanate. The isocyanate functionality of the polyisocyanate is preferably 2.5 to
It is 3.0.

The low shrinkage agent (c) is, for example, vinyl chloride /
It is selected from vinyl acetate copolymers, polystyrene, saturated polyesters, saturated polyester / polyvinyl chloride mixtures and methacrylate homopolymers or copolymers.

The filler (d) is, for example, metal powder such as iron powder and aluminum powder, glass powder, silica powder, calcium carbonate, inorganic filler and pigments such as calcium carbonate and aluminum hydroxide, and fibers such as milled fiber and vinylon. It is a material.

The unsaturated polyester resin (e) is, for example,
can be derived from (i) maleic acid and / or fumaric acid, (ii) phthalic acid and / or isophthalic acid and / or terephthalic acid, (iii) ethylene glycol and / or propylene glycol, and (iv) alkoxylated bisphenols .

The vinyl ester resin (e) is obtained by reacting an epoxy resin with (meth) acrylic acid and, if necessary, further urethanized the hydroxyl group with unsaturated urethane.

The compound (f) having a plurality of (meth) acrylate groups has the general formula:

[Chemical 3] Where Q is the organic residue remaining after removing the hydroxyl groups from the organic polyol and n is an integer of at least 2. The organic polyol can be a simple diol such as ethylene glycol, propylene glycol, diethylene glycol, 1,4-butanediol or 1,6-hexanediol: triol, such as glycerine or trimethylolpropane: or a higher functionality polyol. Other suitable polyols include polyester polyols such as the reaction products of the above-mentioned polyols with dicarboxylic acids such as adipic acid and polyether polyols such as polyoxyalkylene polyols based on ethylene oxide and / or propylene oxide. Still other polyols include bis-glycidyl ethers of bisphenols and oxyethylenated or oxypropyleneized bisphenols.

Thus, compound (f) is a reaction product of a (meth) acrylol halide such as chloride with a diol derived by ethoxylation and / or propoxylation of bisphenol, eg US Pat. No. 2,89.
No. 0,202, the formula:

[Chemical 4] May be a compound represented by

Polymerization of the above-mentioned polymerizable composition is usually carried out by bulk polymerization, but the form of polymerization is not limited to this. In the case of bulk polymerization, the polymerization can be carried out using methods well known in the art.

As the polymerization initiator, a wide range of polymerization initiators can be used in various concentrations depending on the desired polymerization temperature and polymerization rate. The polymerization initiator may be, for example, peroxides such as benzoyl peroxide, acetylacetone peroxide, methyl ethyl ketone peroxide and the like. The polymerization initiator may be used in combination with a polymerization accelerator such as cobalt naphthenate and a tertiary amine. In many cases suitable combinations are benzoyl peroxide and N, N-dimethylaniline or N, N
-Combination with dimethyl-P-toluidine.

Regarding the blending ratio of the above polymer composition,
The unsaturated urethane (a) is preferably 10 to 90 parts by weight, particularly preferably 25 to 50 parts by weight, and the low-shrinking agent (c) to 100 parts by weight of the total amount of the unsaturated urethane (a) + methyl methacrylate (b). ) Is preferably 1 to 25 parts by weight, particularly preferably 5 to 15 parts by weight, and the filler (d) is preferably 10
To 300 parts by weight, particularly preferably 50 to 150 parts by weight. Unsaturated polyester or vinyl ester resin (e)
And a compound (f) containing a plurality of (meth) acrylate groups
The blending ratio of each is 0 to 100 per 100 parts by weight of the total of unsaturated urethane and methyl methacrylate.
Preference is given to parts by weight and 0 to 50 parts by weight.

[0020]

EXAMPLES Examples and comparative examples of the present invention will be shown below.

First, the preparation of the resin (unsaturated urethane / methyl methacrylate / low-shrinking agent) used will be described.

Resin (A): As polyisocyanate,
186 g of a mixture of 4,4′-diisocyanate diphenylmethane and polymethylene polyphenyl polyisocyanate (average isocyanate functionality of 2.6) was dissolved in 536 g of methyl methacrylate, and 1.6 g of dibutyltin dilaurate was added as a catalyst, followed by 186 g of hydroxyethyl methacrylate were added and the polyisocyanate was reacted with 2-hydroxyethyl methacrylate until the absorption of residual isocyanate groups disappeared by infrared analysis.
Thus, polyurethane polymethacrylate was prepared by reacting the hydroxyl group of 2-hydroxyethyl methacrylate with the isocyanate group of polyisocyanate, and a solution was obtained by dissolving this in methyl methacrylate. Further, 91 g of a copolymer of butyl acrylate and methyl methacrylate in a weight ratio of 1: 9 as a low shrinking agent was stirred and dispersed in the above solution. This resin is referred to as (A).

Resin (B): As a low-shrinking agent, a copolymer (91 g) of vinyl chloride and vinyl acetate (6.1 g in weight ratio) was dispersed by stirring. This resin is referred to as (B).

Example 1 With respect to 100 parts by weight of resin (A), 200 parts by weight of aluminum hydroxide as a filler, 0.15 parts by weight of 8% cobalt naphthenate as a polymerization accelerator, and acetylacetone peroxide as a polymerization initiator. 2.0 parts by weight were each mixed to prepare a polymerizable composition (A) for resin molding.

A master mold was constructed by providing a wooden frame of 15 mm in height on the four sides of a 30 cm × 30 cm square glass plate whose surface was mirror-polished. A gel coat (NC-31173P manufactured by Nippon Fellows Co., Ltd.) was applied to the inner surface of the master mold and cured for 6 hours, and then the polymerizable composition (A) was injected into the master mold at 20 ° C., After leaving for 1 hour, the mold was removed, and a resin mold of 30 cm × 30 cm × thickness 10 mm was molded. The total construction period was 7 hours.

Example 2 To 100 parts by weight of resin (B), 200 glass powder M-500S (manufactured by Nippon Fellows Co., Ltd.) was used as a filler.
By weight, 0.2 parts by weight of dimethylaniline as a polymerization accelerator and 2.0 parts by weight of benzoyl peroxide as a polymerization initiator were mixed to prepare a polymerizable composition (B) for resin molding.

The above-mentioned polymerizable composition (B) was poured into the same master mold as in Example 1 at 20 ° C. without coating with a gel coat, left for 1 hour, and then demolded to obtain 30 cm × 30 cm × thickness 1
A 0 mm resin mold was molded. The entire construction period was 1 hour.

Example 3 200 parts by weight of aluminum hydroxide as a filler, 100 parts by weight of resin (A), unsaturated polyester resin
DK-810 (manufactured by Dainippon Ink and Chemicals, Inc.) as (e) 2
0 parts by weight, 0.15 parts by weight of 8% cobalt naphthenate as a polymerization accelerator, and 2.0 parts by weight of acetylacetone peroxide as a polymerization initiator were added to prepare a polymerizable composition (C) for resin molding. did.

The above-mentioned polymerizable composition (C) was poured into the same master mold as that used in Example 1 (cured 6 hours after application of glucoat) at 20 ° C., left for 1 hour, and then demolded. A 30 cm × 30 cm × 10 mm thick resin mold was molded.
The total construction period was 7 hours. It is considered that the unsaturated polyester added did not cause any abnormal appearance in the mold and was copolymerized with the resin (A).

Example 4 With respect to 100 parts by weight of resin (B), 200 parts by weight of aluminum hydroxide as a filler and 10 parts by weight of R-804 (manufactured by Showa Polymer Co., Ltd.) as a vinyl ester resin (e). ,
0.15 parts by weight of 8% cobalt naphthenate was added as a polymerization accelerator, and 2.0 parts by weight of acetylacetone peroxide was added as a polymerization initiator, to prepare a polymerizable composition (D) for resin molding.

The polymerizable composition (D) was injected at 20 ° C. into the same master mold as used in Example 1 (cured 6 hours after application of the glucoat), left for 1 hour, and then demolded. A 30 cm × 30 cm × 10 mm thick resin mold was molded.
The total construction period was 7 hours. It is considered that the added vinyl ester did not cause any abnormal appearance in the mold and was copolymerized with the resin (A).

Example 5 100 parts by weight of resin (B), 200 parts by weight of metallic aluminum powder "AC-1003" (manufactured by Toyo Aluminum Co., Ltd.) as a filler, unsaturated polyester resin
(e) DK-810 (manufactured by Dainippon Ink and Chemicals, Inc.) 5
A compound containing parts by weight and a plurality of (meth) acrylate groups
5 parts by weight of trimethylolpropane trimethacrylate as (f), 0.2 parts by weight of 8% cobalt naphthenate as a polymerization accelerator, and 2.0 parts by weight of acetylacetone peroxide as a polymerization initiator were added respectively, and resin molding was performed. A polymerizable composition (E) was prepared.

The above-mentioned polymerizable composition (B) was poured into the same master mold as that used in Example 1 (cured in 6 hours after application of glucoat) at 20 ° C., left for 1 hour and then demolded. A 30 cm × 30 cm × 10 mm thick resin mold was molded.
The total construction period was 7 hours. It is considered that the blend of the unsaturated polyester resin and trimethylolpropane trimethacrylate was copolymerized with the resin (B) without causing any abnormal appearance in the mold.

Comparative Example 1 As a master mold, the surface was mirror-polished 30 cm × 30 cm
Gel plate (NC-3173P manufactured by Nippon Fellows Co., Ltd.) was applied to the surface of the square glass plate of No. 3 and cured for 6 hours. Then, the glass fiber (S) is placed on the master mold, and an unsaturated polyester resin containing a polymerization initiator (1.0 part by weight of the initiator to 100 parts by weight of the resin) is injected into the glass fiber (S). Then, the glass fiber (S) was impregnated with the resin while defoaming by reciprocating the roller several times over this. The impregnated layer was cured at 20 ° C. for 6 hours.

Next, the glass fiber (M) was placed on the resin mold, and the glass fiber (M) was impregnated with the resin by the same operation as above. Glass fiber (C) on the impregnated layer
The glass fiber (C) was impregnated with the resin by the same operation as above. The glass fiber (M) was placed again on this impregnated layer, and the glass fiber (M) was impregnated with the resin by the same operation as above. These three impregnated layers were simultaneously cured at 20 ° C. for 6 hours to form glass fibers (M + C + M).

Further, the glass fiber (M) was placed on the three-layer resin mold, and the glass fiber (M) was impregnated with the resin by the same operation as above. Glass fiber (R) on the impregnated layer
The glass fiber (R) was impregnated with resin by the same operation as above. The glass fiber (M) was placed on the impregnated layer, and the glass fiber (M) was impregnated with the resin by the same operation as above. The glass fiber (R) was placed on the impregnated layer, and the glass fiber (R) was impregnated with the resin by the same operation as above. The glass fiber (M) was placed on the impregnated layer, and the glass fiber (M) was impregnated with the resin by the same operation as above. These five impregnated layers were simultaneously cured at 20 ° C. for 24 hours to form a glass fiber (M + R + M + R + M) unsaturated polyester resin mold.

Thus, 9 layers of resin having a total thickness of 10 mm were obtained. The total construction period was 42 hours.

The above glass fibers (S) (M) (C) (R)
Are manufactured by Asahi Fiber Glass Co., Ltd., (S) is surface mat SM3600E,
(M) is strand mat CM450, (C) is glass cloth MG300, (R) is roving cloth RH
It is 600.

The unsaturated polyester resin is 158BQTN manufactured by Showa Highpolymer Co., Ltd. The polymerization initiator is methyl ethyl ketone peroxide “Permec N” manufactured by NOF CORPORATION.

Comparative Example 2 Polyurethane resin SDACAST mixed with SADCAST 1875 (manufactured by Taiyo Kikai Co., Ltd.) as a point where no surface gel coat was applied and as an isocyanate type polymerization initiator
537 (manufactured by Taiyo Foundry Co., Ltd.) (36 parts by weight of a polymerization initiator relative to 100 parts by weight of resin) was used instead of the resin (A), and the same operation as in Example 1 was performed, A resin mold was molded. The total construction period was 72 hours.

Comparative Example 3 Epoxy resin Virgin G49 (manufactured by Nippon Sika Co., Ltd.) mixed with Virgin HL80 (manufactured by Nippon Sika Co., Ltd.) as a surface gel coat and amine polymerization initiator.
A resin mold was molded in the same manner as in Example 1, except that (manufacturing) (36 parts by weight of polymerization initiator relative to 100 parts by weight of resin) was used instead of the resin (A). The total construction period was still 72 hours.

Evaluation Test The evaluation results of the performance of the resin types obtained in the examples and comparative examples are shown below.

[Table 1] The measurement results of the surface smoothness and the surface smoothness after 10 times of use are shown in the attached drawings.

The measuring method of each item is as follows.

Surface smoothness: Measured using a surface roughness measuring device SE-40D manufactured by Kosaka Laboratory Ltd.

Measurement conditions: feed rate 0.5 mm / sec, reference length 25.0 mm, cutoff value 0.8 mm.

Warp: A right-angled ruler was applied to the surface of the demolding die, and the warp in the vertical direction from the horizontal plane was measured.

Linear shrinkage: The actual length was measured.

Surface smoothness after 10 times of use: FRP (gel coat + M + M) was molded using each resin mold, and 60 ° C.
After 3 hours of curing, the mold was removed, and this was repeated 10 times, and the smoothness of the mold surface was examined. M is Asahi Fiber Glass Co., Ltd.
CM450 manufactured by Fiberglass Strand Mat.

As is clear from Table 1, the resin molds obtained in the examples showed excellent results in all items as compared with those in the comparative examples.

[0050]

According to the present invention, the resin is completely cured in a short time without heating and heating from the outside, and the dimensional accuracy is good, and the molding surface is not deformed or cracked and is excellent in durability. The resin mold can be easily manufactured in an extremely short construction period.

[Brief description of drawings]

FIG. 1 is a diagram showing a measurement result of surface smoothness.

FIG. 2 is a diagram showing a measurement result of surface smoothness after 10 times of use.

FIG. 3 is a diagram showing measurement results of surface smoothness.

FIG. 4 is a diagram showing a measurement result of surface smoothness.

FIG. 5 is a diagram showing the measurement results of surface smoothness after 10 times of use.

FIG. 6 is a diagram showing a measurement result of surface smoothness.

FIG. 7 is a diagram showing the measurement results of surface smoothness after 10 times of use.

FIG. 8 is a diagram showing a measurement result of surface smoothness.

FIG. 9 is a diagram showing the measurement results of surface smoothness after 10 times of use.

FIG. 10 is a diagram showing a measurement result of surface smoothness.

FIG. 11 is a diagram showing the measurement results of surface smoothness after 10 times of use.

FIG. 12 is a diagram showing a measurement result of surface smoothness.

FIG. 13 is a diagram showing the measurement results of surface smoothness after 10 times of use.

FIG. 14 is a diagram showing a measurement result of surface smoothness.

FIG. 15 is a diagram showing the measurement results of surface smoothness after 10 times of use.

Claims (4)

[Claims] 1. Reaction of (a) a hydroxyl group of a hydroxyalkyl (meth) acrylate with an isocyanate group of a polyvalent isocyanate having no urethane group and having an isocyanate functionality of more than 2.0. Obtained by
Polyvalent (meth) acrylates bets, (b) methyl methacrylate, (c) vinyl comprising a polymer low profile additive and (d) a resin molding for polymer compositions comprising a filler. Wherein (a) the reaction of the hydroxyl group of a hydroxyalkyl (meth) acrylate, polyhydric iso <br/> isocyanate groups cyanate having an isocyanate functionality of over and 2.0 no urethane groups Obtained by
Polyvalent (meth) acrylates bets, (b) methyl methacrylate, (c) and a low profile additive comprising a vinyl polymer and (d) filler, (e) an unsaturated polyester or vinyl ester resin and / or (f) General formula: Polymerization for resin molding comprising a compound having a plurality of (meth) acrylate groups represented by the formula (wherein R represents a hydrogen atom or a methyl group) and having neither a urethane group nor a hydroxyl group. Sex composition. 3. A resin mold molded from the polymerizable composition according to claim 1. 4. A resin mold molded from the polymerizable composition according to claim 2.