JPH0549009B2 - - Google Patents

Description

[Detailed description of the invention]

[Industrial Field of Application] The present invention relates to a method for manufacturing molded products such as bathtubs, washstands, system kitchen worktops, tiles, etc., which are required to have both aesthetic appearance and water resistance. [Prior Art] In the case of artificial marble, which is very pale in color and whose vitality is transparency, the appearance of the molded product is an important item in determining its commercial value, as well as the physical properties of the molded product. In addition, casting up to a thickness of 10m/m, and even 1m
In the case of the above-mentioned large molded products, it is critically important to prevent cracks from occurring during molding. Conventionally, the resin for casting this artificial marble is
Existing radical curable resins, such as unsaturated polyester resins and vinyl ester resins, have been used. Of course, these existing resins are useful, and various molded products are manufactured and sold commercially. However, it is true that further improvements are required in view of the above-mentioned desire to improve the appearance, as well as to improve safety during molding and increase product yield. [Problems to be Solved by the Invention] In view of the above-mentioned circumstances, the present invention provides a product that does not cause cracks, has an improved appearance, and is also fully satisfactory even in a so-called single-sided boiling test in which only the gel coated surface is brought into contact with boiling water. The purpose of this invention is to provide a method for producing fiber-reinforced plastic molded products (hereinafter referred to as FRP molded products) with good yield. [Means for Solving the Problems] That is, the present invention applies a gel coat to a mold, and then provides (with or without providing a layer of fiber reinforcing material in the next layer) via a urethane bond or an ester bond in the side chain. By setting a mixture of a filler and a side chain unsaturated polymer having a meth)acryloyl group and a main chain having a carbon-carbon bond as an intermediate layer, and further providing a backing layer of a fiber reinforcing material, the above-mentioned The present invention relates to a method for manufacturing a molded article exhibiting excellent physical properties, which solves the above problems. [Function] Compared to conventional unsaturated polyester resins and vinyl ester resins, the side chain unsaturated polymer used as the intermediate layer in the present invention has a large molecular weight and is stable because its main chain is a carbon-carbon bond polymer. It has high strength, and has a reactive (meth)acryloyl group at the end of the side chain, so it has excellent curability. Therefore, by using this resin as an intermediate layer and laminating and reinforcing fiber reinforcing material on one or both sides, the FRP molded product of the present invention with excellent boiling resistance and no cracks can be produced in high yield. estimated to be obtained. The side chain unsaturated polymer used in the present invention is a curable polymer having a (meth)acryloyl group in the side chain via a urethane bond or an ester bond, and the main chain is a carbon-carbon bond. A vinyl polymer having a functional group such as a hydroxyl group, a carboxyl group, or a chrycidyl group is produced, and then the functional group is reacted with a compound that shares a reactive group that performs a urethanization or esterification reaction and a (meth)acryloyl group. Manufactured by Typical manufacturing methods and specific examples include the following. (1) A side chain unsaturated polymer having a (meth)acryloyl group in the side chain via a urethane bond (a) [A] similar to those described in JP-A-59-230019 and JP-A-60-38403; A polymer containing a hydroxyl group in the side chain and [B] an unsaturated isocyanate having a free isocyanate group which is an adduct of a polyvalent isocyanate and an unsaturated monoalcohol having a (meth)acryloyl group are combined into a polymerizable monomer. Examples include curable side-chain unsaturated polymers obtained by reacting the hydroxyl group of [A] and the isocyanate group of [B] in a polymer. Among them, polymers represented by the following general formula [] are preferably used in the present invention. [However, R ₁ and R ₂ are hydrogen or a methyl group, G represents a diisocyanate residue, M is 50 to 300, n is 70 to 99, and m is 1 to
30, l is an integer of 2 or 3. ] Specifically, a copolymer of 2-hydroxylethyl (meth)acrylate or 2-hydroxypropyl (meth)acrylate and styrene is used as the polymer containing a hydroxyl group in the side chain, and isophorone di-styrene is used as the unsaturated isocyanate. Isocyanate, 2,4-tolylene diisocyanate,
A 1:1 mol or 1 mol or more adduct of 2-hydroxyethyl (meth)acrylate or 2-hydroxypropyl (meth)acrylate is reacted with a diisocyanate whose two isocyanate groups have different reactivities, such as The best one is the one that can be obtained. (b) Examples include curable side chain unsaturated polymers obtained by reacting the aforementioned polymer containing a hydroxyl group in the side chain with (meth)acryloyloxyethyl isocyanate. (c) A polymer containing isocyanate in the side chain obtained by copolymerizing (meth)acryloyloxyethyl isocyanate with other vinyl monomers such as styrene and methyl methacrylate, and an unsaturated polymer having a (meth)acryloyl group. Examples include side chain unsaturated polymers obtained by reacting with alcohol. (2) a side chain unsaturated polymer having a (meth)acryloyl group in the side chain via an ester bond; (d) a polymer having a glycidyl group in the side chain;
It is a side chain unsaturated polymer obtained by reacting with (meth)acrylic acid, and the polymer represented by the following general formula [] is typical. [However, the definitions of R ₁ , R ₂ , M, n and m are the same as above. ] Specifically, (meth) is added to a copolymer of styrene and glycidyl (meth)acrylate.
Preferably, it is obtained by subjecting acrylic acid to an esterification reaction. Moreover, those using allyl glycidyl ether instead of glycidyl (meth)acrylate are also preferably used. (e) a polymer containing a carboxyl group in its side chain;
Examples include polymers represented by the above general formula [] obtained by reacting with an unsaturated epoxy compound. Specifically, a material obtained by reacting a copolymer of styrene and (meth)acrylic acid with glycidyl (meth)acrylate is suitable. (F) [A] For 1 mole of (meth)acrylic acid, as typified by JP-A No. 61-258817 "Curable resin and method for producing the same",
A component containing as at least one component an unsaturated epoxy resin having a (meth)acryloyl group and an epoxy group in the molecule obtained by reacting with 1 mole or more of an epoxy resin and a vinyl monomer are co-coated using a radical polymerization catalyst. By polymerizing, a polymer-containing reaction mixture having epoxy groups in the side chains of the resulting polymer is produced, and then [B] substantially equimolar amount of the epoxy groups remaining in the reaction mixture obtained from step [A] is prepared. Examples include side-chain unsaturated polymers obtained by adding (meth)acrylic acid and reacting epoxy groups with carboxyl groups. Among these, polymers represented by the following general formula [] are preferred. [However, R ₁ , R ₂ , M, n, and m are the same as above. R ₃ and R ₄ are hydrogen or a methyl group, and p is an integer of 0 to 5. ] Similarly, in place of the bisphenol type epoxy resin, a novolac type epoxy resin or an alicyclic epoxy resin may also be suitably used. (g) Polymers containing carboxyl groups in their side chains,
Examples include side-chain unsaturated polymers represented by the general formula [] obtained by reacting the above-mentioned unsaturated epoxy resins. The epoxy resin used is the same as above. (H) A side chain unsaturated polymer obtained by reacting an unsaturated alcohol having a (meth)acryloyl group with a polymer having an acid anhydride group in the side chain can be mentioned. Among them, polymers represented by the following general formula [] are preferably used. [However, R ₁ , R ₂ , n, m and M are as described above. ] Specifically, a copolymer of styrene and maleic anhydride is used as a polymer having an acid anhydride group, and it is obtained by reacting it with 2-hydroxyethyl (meth)acrylate or 2-hydroxypropyl (meth)acrylate. The best option is the one that can be used. Furthermore, a polymer free of free carboxyl groups obtained by reacting the free carboxyl groups resulting from esterification with a monomer having an epoxy group or a hydroxyl group and a (meth)acryloyl group is also applicable to the method of the present invention. It can be used in The above side chain unsaturated polymers have a molecular weight of 5000 or more,
Desirably 10,000 or more and 100,000 or less. If the molecular weight is less than 5,000, the curing properties and physical properties are not necessarily sufficient, and if it is more than 100,000, the viscosity becomes high and workability becomes poor. The ratio of (meth)acryloyl groups in the side chain unsaturated polymer is preferably 1 mol % or more and 30 mol % or less. The most suitable range is 5 mol% or more and 20 mol% or less. These side-chain unsaturated polymers are used as a mixture with monomer solutions, for example styrene monomers. The mixing ratio is usually 30 to 70%, preferably 40 to 60% in terms of polymer concentration. When casting and curing resin, a filler is usually used in combination with the casting resin to provide a suitable degree of transparency and to prevent cracks due to heat generation during curing and molding. When transparency is required, glass flakes,
Fine glass powder, hydrated alumina (aluminum hydroxide), fine silica powder, etc. are useful. If transparency is not required, calcium carbonate,
clay, alumina, mica, barite, gypsum,
Micro balloons etc. are selected as necessary. Among these, glass flakes are particularly effective in providing transparency and preventing cracks. Glass flakes are approximately 50 to 400 microns in size.
It is a flat material with a thickness of 2 to 10 microns, such as glass flake CF manufactured by Nippon Glass Fiber Co., Ltd. Other uses include glass powder.
The most representative example is the product name "Frits" manufactured by Nippon Fellow Co., Ltd. The mixing ratio of the filler and the side chain unsaturated polymer can be selected arbitrarily, but considering the viscosity and painting workability, the mixing ratio (wt%) of the filler should be approximately 10 to 80.
%, preferably 40 to 60%. The gel coat resin used in the present invention, the backing laminating resin, and the laminating resin for the next laminated part of the gel coat used as necessary are conventional resins such as unsaturated polyester resins, vinyl ester resins, and acrylic urethane resins. radical curable resins can be used. Of course, the aforementioned side-chain unsaturated polymers of the present invention can also be used. The unsaturated polyester resin contains an α-β unsaturated polybasic acid or its acid anhydride as an essential component,
It is a form in which an unsaturated polyester obtained by esterification with a polyhydric alcohol, with or without a saturated acid, is dissolved in a copolymerizable monomer such as styrene. The polyhydric alcohol components used in the present invention include neopentyl glycol, hydrogenated bisphenol A, and bisphenol A propylene oxide adducts, which provide hot water resistance to the cured resin, and the saturated acid is isophthalate. acid,
Terephthalic acid is preferred. Vinyl ester resins are synthesized by reaction of epoxy groups and carboxyl groups using epoxy resins and (meth)acrylic acid. As the epoxy resin, a bisphenol-glycidyl ether type resin having a molecular weight of 350 to 700 is suitable. In addition to (meth)acrylic acid, it is also practical to use polybasic acids or their acid anhydrides together. The form utilized in the present invention is dissolved in a copolymerizable monomer such as styrene. Usually, the styrene monomer is used in a proportion of 40 to 60% by weight, more generally about 50% by weight, based on the resin. Acrylic urethane resin is an unsaturated urethane resin that contains as one component an unsaturated alcohol having an acryloyl group or a methacryloyl group, and is obtained by reacting a polyhydroxy compound or its polymer, and diisocyanate, and is typically represented by the following formula. Examples include those shown in . [Wherein R is -H or _-CH3 ]. Other polyhydric alcohol polyacrylates,
Oligoacrylates such as spiroacetal diacrylates are also available. The fiber reinforcing material used in the present invention is generally made by cutting and spraying glass fiber mat or roving, but roving cloth or cloth can also be used if necessary. A refractive index of 1.54 to 1.55 is required to provide transparency to molded products.
It is preferable to use glass fiber. The molded product can be colored as desired, and the molding method can be carried out in a conventional manner. [Example] Next, in order to help the understanding of the present invention, examples are shown below. Example 1 Production of side chain unsaturated polymer (a) having a (meth)acryloyl group via a urethane bond in the side chain Styrene, hydroxyethyl methacrylate, t-dodecyl mercaptan and n - A predetermined amount of dodecyl mercaptan was charged and copolymerization was carried out at a predetermined temperature.
Samples were taken periodically and the molecular weight was determined. When a predetermined molecular weight is reached, a predetermined amount of a diluent consisting of styrene as a diluent monomer, hydroquinone as a polymerization inhibitor, and dibutyltin dilaurate as a catalyst is poured into an autoclave and heated at 60°C.
The mixture was stirred for 0.5 hour while maintaining the temperature. Then 180 parts of isophorone diisocyanate and 144 parts of 2-hydroxypropyl methacrylate
An equivalent amount of an unsaturated isocyanate that shares a methacryloyl group and an isocyanate group was added to the molecule obtained by reacting the methacryloyl group with the isocyanate group, and urethanization was performed at 60°C until the isocyanate group disappeared. The reaction time was approximately 6 hours. To 100 parts of the obtained curable resin, 2 parts of a peroxide catalyst (manufactured by Kayaku Nouri Co., Ltd., 328E), 0.5 parts of cobalt naphthenate (containing 6% cobalt), and 0.3 parts of acetylacetonate of dimethylaminoethanol were blended. The material was cured at room temperature and its physical properties were measured.

【table】

[Table] Production of gel coat (A) Add Erosil Rx- to 100 parts of the side chain unsaturated polymer (A).
200 and 0.05 part of Phthalocyanine Blue were roll-kneaded to obtain gel coat (A). Production of flake compound (a) 100 parts of side chain unsaturated polymer (a), Erosyl Rx-
4 parts of 200, 70 parts of CF-150 as glass flakes
First, 2 parts of the coupling agent (A-174) were mixed with Erosil in three rolls, and the remaining ingredients were mixed in with a mixer to form a flake compound (A). Preparation of test piece (A) Gel coat (A) on glass plate treated with mold release agent.
Add 2 parts of Nippon Oil & Fats Co., Ltd. Perbutyl PV to 100 parts, 0.6
Paint with a bar coater so that it becomes m/m, 60
After gelling by heating for 30 minutes at ℃, apply flake compound (A) prepared by adding 1 part of Parkadox #16 to 100 parts of flake compound to a thickness of about 1 m/m, and The gel was heated at ℃ for 30 minutes. As a polyester resin, a composition of 2.1 mol of propylene glycol, 1 mol of maleic anhydride, and 1 mol of phthalic anhydride was esterified by heating, and oxidized to 35.4 mol.
The unsaturated polyester was then dissolved in 40% styrene by weight containing 300 ppm of hydroquinone to produce a polyester resin. 1 part of Erosil R-200 and 0.5 part of cobalt naphthenate were mixed with 100 parts of this polyester resin, and immediately before use, 1 part of methyl ethyl ketone peroxide was added to prepare a backing resin. On top of the flake compound layer, three layers of #350 glass mat and the aforementioned polyester resin for backing were laminated, followed by adhering and curing Mylar film. It was heated at 80° C. for 2 hours and at 120° C. for 1 hour for post-curing to produce a test laminate ( ). Comparative Example 1 A laminate (2) was produced by molding in the same manner from the same sample except that the flake compound (A) was not applied, that is, only the gel coat (A) and the backing laminate. The gel coated surface was brought into close contact with a boiling test container having holes of 100 m/m in diameter through silicone rubber packing, and a continuous boiling test was conducted in boiling water at 98 to 100°C. As shown in Table 2, the results demonstrated that the flake compound coated laminate (2008) was significantly superior.

[Table] Example 2 In the same polymer as in Example 1 having a hydroxyl group in the side chain, as an unsaturated isocyanate, instead of the reaction product of isophorone diisocyanate and 2-hydroxypropyl methacrylate,
A side chain unsaturated polymer (b) was synthesized by carrying out the same reaction as in Example 1 except for using 116 parts of isocyanatoethyl methacrylate. Production of gel coat (b) Add Erosyl Rx- to 100 parts of side chain unsaturated polymer (b).
200, 2 parts of Perbutyl PV, and 1 part of silane coupling agent A-174 were roll-kneaded to obtain a gel coat (B). Production of casting resin (b) 100 parts of side chain unsaturated polymer (b), Nippon Ferro
170 parts of Fritz 10B manufactured by Co., Ltd., 2 parts of Perbutyl PV
1 part, add 2 parts of silane coupling agent A-174,
A casting resin (b) was manufactured. Manufacture of test piece Gel coat (RO) is applied on a glass plate treated with a mold release agent.
was coated with a bar coater to a thickness of 0.6 to 0.7 m/m, heated at 60°C for 30 minutes to gel, and then #
Lay a layer of 350 pine and impregnate it with gel coat (b).
After defoaming, heat at 60°C for 30 minutes to gel. Use this as one side and adjust the thickness separately to 2m/m.
The casting resin (b) was injected under reduced pressure and defoamed at 10 m/m between glass mats and ivory-colored FRP boards using polyester resin. It was cured by heating at 60°C for 2 hours and at 70°C for 2 hours. After removing the mold from the glass plate, it was cut into desired dimensions to obtain test pieces. Example 3 Production of side chain unsaturated polymer (c) Toluene was placed in a two-separable flask equipped with a stirrer, reflux condenser, thermometer, and gas inlet tube.
1000 g of styrene, 400 g of styrene, 60 g of isocyanate ethyl methacrylate, 5 g of α-methylstyrene dimer, and 1 g of azobisisobutyronitrile were charged, and the mixture was replaced with _N2 for 30 minutes. Meanwhile, the temperature of the liquid
The temperature was increased to 90°C and polymerization was carried out at this temperature for 4 hours. The polymerization rates of styrene and isocyanatoethyl methacrylate by gas chromatography were 63% and 73%, respectively.
%, and the weight average molecular weight by liquid chromatography is 5.3
It was ×10 ⁴ . Lower the liquid temperature to 60°C, add 130 parts of hydroxyethyl methacrylate, 1 part of dibutyltin dilaurate, and 0.1 g of phenothiazine.
The urethanization reaction was carried out at ℃ for 5 hours until the isocyanate group disappeared. An additional 60 parts of styrene was added, and toluene was distilled off under reduced pressure to obtain a side chain unsaturated polymer (iii). Hereinafter, a boiling test was conducted in the same manner as in Example 2. Example 4 Production of side chain unsaturated polymer (2) having a (meth)acryloyl group via an ester bond in the side chain Production of unsaturated epoxy resin (a) Stirrer, thermometer with gas introduction tube, reflux condenser, dropping In a separable flask equipped with a funnel, 360 g (1 mol) of Mitsubishi Yuka-Ciel's Epicote 827 as an epoxy resin and 43 g of methacrylic acid.
(0.5 mol), benzyldimethylamine 1.2 g, and parabenzoquinone 0.08 g are reacted for 3 hours at 120-130°C under nitrogen blowing conditions. The acid value becomes almost zero and the unsaturated epoxy resin (a) turns into a light reddish brown syrup. Obtained as follows. For resin (a), the following formula [] is calculated as 223g, It is a mixture with 180 g of free epoxy resin. Synthesis of side chain epoxy resin (b) Into the same apparatus as above, 250 g of methyl ethyl ketone,
173 g (0.2 mol) of unsaturated epoxy resin (a), 100 g of styrene, and 3.5 g of azobisisobutyronitrile were charged, and 87 g of styrene (total amount of styrene: 1.8 mol) was added dropwise at 75° C. in a nitrogen stream. After 6 hours, add 2 more azobisisobutyronitrile
g was added, and the polymerization was further continued for 10 hours. When the polymerization rate reaches 96%, hydroquinone
Polymerization was stopped by adding 0.2 g. A solution of side chain epoxy resin (b) in methyl ethyl ketone (solid content 40%) was obtained in the form of a pale yellowish brown liquid. As a result of GPC analysis, it was confirmed that it was a mixture of a polymer with a peak at a molecular weight of about 50,000 and unreacted epoxy resin. Synthesis of side chain unsaturated polymer (d) Add 52 g (0.60 mol) of methacrylic acid to the entire methyl ethyl ketone solution of the side chain epoxy resin (b) described above.
When 0.8 g of triphenylphosphine is charged and reacted for 16 hours at the boiling point of methyl ethyl ketone, the acid value is
10.4, 420 g of styrene monomer was added and heated under reduced pressure of 400 to 450 mmHg to remove methyl ethyl ketone. After about 6 hours, gas chromatographic analysis showed that methyl ethyl ketone was 0.3%, so heating was discontinued, and side chain unsaturated polymer (d) was obtained with a yellowish brown color and a viscosity of 1.9 poise. Side chain unsaturated polymer (d) 100 parts Perkyure SA (manufactured by NOF Corporation) (peroxide catalyst)
A mixture of 1 part cobalt naphthenate (6% Co) and 0.5 parts was gelled at room temperature for 11 minutes, with a minimum cure time of 11.4 minutes and a maximum exotherm temperature of 157°C. The cured resin had the following excellent physical properties: Tensile strength (Kg/mm ² ) 6.9-7.4 Bending strength (Kg/mm ² ) 13.7-15.9 Bending modulus of elasticity (Kg/mm ² ) 322- 369 Heat distortion temperature (°C) 124 Test pieces were prepared in the same manner as in Example 2, and a boiling test was conducted. Example 5 Production of a side chain unsaturated polymer (e) having a (meth)acryloyl group via an ester bond in the side chain [Production of styrene-glycidyl methacrylate copolymer] Equipped with a pressure regulator, a pressure gauge, and a safety valve. Inner diameter 4
Styrene (76% by weight) and glycidyl methacrylate (23% by weight) were placed in a stainless steel reactor with mmφ and length of 1.5m.
wt%), n-dodecyl mercaptan (1 wt%)
The mixture was fed at a rate of 1.7 g/min,
The reaction was carried out under conditions of ~7 Kg/cm ² . As a result, the reaction rate of styrene was 58%, the reaction rate of glycidyl methacrylate was 73%, and a colorless and transparent sticky copolymer composition was obtained. [Production of side chain unsaturated polymer (e)] In a separable flask (1000 ml) equipped with a stirrer, thermometer, and reflux condenser, add the above copolymer composition (200 g), styrene (200 g), and methacrylic acid (27.9 g). , 0.32 mol) and hydroquinone (0.2 g) were added and reacted at 100°C for 5 hours. As a result, the reaction rate of methacrylic acid was 95%, and the resulting solution of the side chain unsaturated polymer (e) was pale yellow and transparent, and the viscosity at 25°C was 15 poise. 1 part of "Permec N" (trade name, peroxide catalyst manufactured by NOF Corporation) per 100 parts of the above polymer solution,
When 0.5 part of cobalt naphthenate (6% Co) was added and a room temperature gelling test was performed, gelation time was 12 minutes,
The shortest curing time was 14.3 minutes, and the maximum exothermic temperature was 140°C. Furthermore, the cured resin had the following physical properties and was excellent in transparency. Tensile strength 7.4Kg/mm ² Bending strength 15.9Kg/mm ² Flexural modulus 369Kg/mm ² Heat deformation temperature 125°C Below, using the solution of the above side chain unsaturated polymer (e), the same procedure as in Example 2 was carried out. A boiling test was conducted using the method. Example 6 Production of side chain unsaturated polymer (f) having a (meth)acryloyl group via an ester bond in the side chain [Production of styrene-methacrylic acid copolymer] Equipped with a pressure regulator, pressure gauge, and safety valve. Inner diameter 4
A mixture of styrene (76% by weight), methacrylic acid (23% by weight), and n-dodecyl mercaptan (1% by weight) was fed into a styrene reactor with mmφ and length of 1.5 m every minute.
It was fed at a rate of 2.0 g and reacted at 200° C. and 5 to 7 Kg/cm ² . As a result, the reaction rate of styrene is
The reaction rate of methacrylic acid was 72%, and a colorless and transparent sticky copolymer composition was obtained. [Production of side chain unsaturated polymer (f)] The above copolymer composition (200 g), styrene (200 g), and glycidyl methacrylate (76.0 g) were placed in a separable flask (1000 ml) equipped with a stirrer, thermometer, and reflux condenser. ) and hydroquinone (0.2 g) were added and reacted at 100°C for 5 hours. As a result, the reaction rate of glycidyl methacrylate was 93%,
The resulting solution of the side chain unsaturated polymer (f) was pale yellow and transparent, and had a viscosity of 9 poise at 25°C. 1 part of "Permec N" (trade name, peroxide catalyst manufactured by NOF Corporation) per 100 parts of the above polymer solution,
When 0.5 part of cobalt naphthenate (6% Co) was added and a room temperature gelling test was performed, gelation time was 11 minutes,
The shortest curing time was 11.4 minutes, and the maximum exothermic temperature was 156°C. Furthermore, the cured resin had the following physical properties and was excellent in transparency. Tensile strength 7.0Kg/mm ^2Bending strength 13.8Kg/mm ^2Bending modulus of elasticity 323Kg/mm ^2Heat distortion temperature 125℃ Below, the same procedure as in Example 2 was carried out using the solution of the above side chain unsaturated polymer (f). A boiling test was conducted using the following method. Example 7 Synthesis of side chain unsaturated polymer (g) having methacryloyl group in side chain via ester bond, stirrer,
In a two-separable flask equipped with a reflux condenser, a gas inlet tube with a thermometer, and a dropping funnel, add 728 g of styrene, 10 g of t-butyldodecyl mercaptan,
A mixture of 200 g of methyl methacrylate and 98 g of maleic anhydride was added dropwise at a temperature of 100° C. in a nitrogen stream. After the dropwise addition was started, the temperature was raised to 120°C, and the dropwise addition was completed at the same temperature for 4 hours. After finishing dropping,
If you continue heating at the same temperature for another hour, the solid content will be 45
(%) In molecular weight measurement by GPC
It peaked at 28,000. Lower the temperature to 100℃, add 0.2g of hydroquinone, 130g of 2-hydroxyethyl methacrylate, and 2g of para-toluenesulfonic acid, and react at the same temperature for 6 hours. As a result of infrared analysis, the absorption of acid anhydride in the polymer was approximately 70%.
(%) was determined to have disappeared. A side chain unsaturated polymer (T) was obtained with a viscosity of 5.4 poise and a Hazen color number of 300. Hereinafter, a boiling test was conducted in the same manner as in Example 2. Comparative Example 2 A polyester resin (H) having the following formulation was produced. Weigh out 240 g (1 mol) of hydrogenated bisphenol A, 125 g (1.2 mol) of neopentyl glycol, and 166 g (1 mol) of isophthalic acid into a reaction vessel.
After esterification at 210℃ in a nitrogen stream to give an acid value of 30.1, 116g (1 mol) of fumaric acid was added, further esterification was carried out under the same conditions, and when the acid value was 34.7, 0.15g of hydroquinone was added, and styrene was added at a temperature of 155℃. 525g
It was dissolved in to form a polyester resin (H). It had a viscosity of 4.7 poise and a Hazen color number of 350. A boiling test similar to Example 2 was conducted. The above results are summarized in Table 3.

[Table] Example 8 [Manufacture of vinyl ester resin (li) for gel coat] In a 1 g separable flask equipped with a stirrer, reflux condenser, gas inlet tube, and thermometer, a bisphenol type liquid resin with an epoxy equivalent of 175 was added as an epoxy resin. (Yuka Ciel Epoxy Co., Ltd. Epicote 827)
and 75 g of isophthalic acid, reacted at 170 to 190℃ for 3 hours in a nitrogen stream, and then lowered the temperature to 135℃.
0.3g of hydroquinone, methacrylic acid
86g of trimethylbenzylammonium chloride, 0.5g of chromium naphthenate, and 1.5g of chromium naphthenate were charged, and after reacting for 3 hours at 130-135℃ in an air stream, styrene
When 100 g was added and the reaction was further continued at 115-120°C for 1 hour, the acid value became 9.1. At this stage, 380 g of styrene was further added to synthesize vinyl ester resin (li) for gel coat. This resin had a Hazen color number of 350 and a viscosity of 11.4 poise. [Manufacture of casting resin (urethane type unsaturated polymer)] Styrene was placed in a two-separable flask equipped with a stirrer, reflux condenser, gas inlet tube, and thermometer.
Weighed out 936 g and 130 g of 2-hydroxyethyl methacrylate (HEMA), and heated them at 120°C in a nitrogen stream for 6 hours.
After heating for a period of time, the reaction rate reaches approximately 42%, and free
As a result of gas chromatography analysis, it was determined that HEMA amounted to about 14% of the initial amount. Add 0.2g of hydroquinone and lower the temperature to 70℃.
Switch to air flow, add 140 g of isocyanate ethyl methacrylate and 3 g of dibutyltin dilaurate, and react at 70°C for 5 hours, resulting in a Hazen color number of 30 and a viscosity.
A casting resin (Li) of 11.4 poise was obtained. Infrared analysis confirmed that free isocyanate had disappeared. (Formation of gel coat layer) 100 parts by weight of vinyl ester resin (the same applies below)
5 parts of Erosil R-200 was added to the mixture and kneaded with a three-roll mill to impart thixotropy. To 100 parts of this resin, 0.5 part of a coupling agent (Nitto Unicar Co., Ltd. A-174), 2 parts of "Darocure #1173" manufactured by Merck & Co. as a photoinitiator, and 1 part of "Parkadox #16" manufactured by Kayaku Nury Co., Ltd. were added as photoinitiators. The gel coat of the present invention is produced by adding a part to the gel coat composition (re).
And so. On a 30cm x 30cm x 5mm glass plate coated with a release agent, apply gel coat (re) to a thickness of 0.5mm using a bar coater, wait until the coated surface becomes uniform,
Sun lamp with output of 250W (manufactured by Stanley Electric Co., Ltd.)
When irradiated for about 15 minutes at a position 30 cm below, the gel coat layer was hardened to the extent that it was dry to the touch. (Casting, heating, and curing) On one side of this, another 2 mm thick FRP made of white colored glass mat was placed, and the interval between them was 10 mm. ) 100 parts, 200 parts of Fritz B-10 manufactured by Nippon Ferro Co., Ltd., Perbutyl PV manufactured by Nippon Oil & Fats Co., Ltd.
1.5 parts, mixed, degassed and cast at 70℃ for 2 hours, 80℃
It was allowed to cure for 2 hours. After cooling and demolding, a molded product (Re) was obtained. Comparative Example 2 To 100 parts of vinyl ester resin (Li), 1.5 parts of Kayaku Nouri Co., Ltd. 328E as an organic peroxide, 0.3 parts of cobalt naphthenate (6% Co), and Nippon Fine Chemical Co., Ltd. as a curing accelerator. ) 0.3 parts of ST Cure and 5 parts of Erosil R-200 were added to prepare a gel coat composition (nu),
This was coated on a glass plate in the same manner as in Example 1, photocured, cast with resin (Li), and heated and cured to obtain a molded article (N). Each molded article obtained in Example 1 and Comparative Example 2 was
The material was cut into pieces of cm x 15 cm, placed in a boiling test container with four circular openings each side having a diameter of 10 cm, with the gel coat layer facing inside, and a boiling test was conducted at a temperature of 98 to 99°C. The results are shown in Table 4. As can be seen from Table 4, the molded articles produced according to the present invention were superior.

【table】

[Table] [Effects of the Invention] According to the method of the present invention, it is possible to produce molded products at low cost, without cracking, and exhibiting excellent boiling resistance, which improves the aesthetic appearance of bathtubs, washstands, tiles, etc. Extremely useful for applications requiring water resistance.

Claims (1)

[Claims] 1 Gel coat is applied to the mold, and then a layer of fiber reinforcing material is provided or not, and the main chain has a (meth)acryloyl group via a urethane bond or an ester bond, and the main chain is a carbon-carbon bond. A method for producing a molded article, characterized in that a mixture of a side chain unsaturated polymer and a filler is set as an intermediate layer, and a backing layer of a fiber reinforcing material is further provided.