JP2005179388A - Curable resin composition, method for producing the same and method for utilizing the same resin composition - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a resin composition exhibiting effects of low styrene evaporating properties, having excellent molding processability and affording a cured molded product having excellent mechanical characteristics and hot water resistance and further improving the surface smoothness of an FRP laminated cured product by low shrinkability and to provide a method for utilizing the curable resin composition. <P>SOLUTION: The curable resin composition comprises (A) an unsaturated polyester having an alkyl alcohol residue with one or more phenyl groups and a dicyclopentadiene residue at the molecular terminals and 1,000-3,000 weight-average molecular weight expressed in terms of polystyrene, (B) an acrylate or a methacrylate oligomer having an acryloyl or a methacrylol group at the molecular terminals and 500-2,000 weight-average molecular weight expressed in terms of polystyrene and (C) a radical-polymerizable monomer. The method for producing the curable resin composition is provided. A resin composite composition is obtained by combining the curable resin composition with a fiber reinforcing material and/or a filler or an aggregate. A method for producing a molded product is characterized by molding and curing the curable resin composition or the composite composition. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a curable resin, a method for producing the same, and a method for using the resin. More specifically, since the curable resin of the present invention has a low viscosity and can reduce the content of a radical polymerizable monomer (for example, styrene) blended in the curable resin composition, it can only reduce radical polymerizable monomer volatility. Rather, the curable resin composition provides a molded product having excellent FRP (fiber reinforced plastic) molding (laminating) workability, excellent mechanical properties and hot water resistance, and further improving the surface smoothness of the FRP laminated cured product. The performance can be improved. The present invention relates to such a curable resin composition, a method for producing the same, and a method for using the curable resin composition.

Thermosetting resins such as unsaturated polyester resins and vinyl ester resins are used as base materials for FRP (fiber reinforced plastic) used in construction materials, transportation equipment, industrial equipment, etc., or as castings, paints, adhesives, resins. Widely used for concrete, decorative board, etc.
Usually, an unsaturated polyester resin is obtained by polycondensing an alcohol component generally composed of a polyhydric alcohol and an acid component composed of an α, β-unsaturated polyvalent carboxylic acid and a saturated polyvalent carboxylic acid or an aromatic polyvalent carboxylic acid. It is a viscous liquid resin obtained by blending the obtained unsaturated polyester with a radical polymerizable monomer, for example, generally styrene. And by changing the ratio of polyhydric alcohol, α, β-unsaturated polyvalent carboxylic acids and saturated polyvalent carboxylic acids and aromatic polyvalent carboxylic acids used in the production of the unsaturated polyester, It is possible to produce an unsaturated polyester resin composition having physical properties suitable for the intended purpose of use or capable of being molded by a molding method suitable for the intended purpose.

Similarly, a vinyl ester resin is a liquid resin obtained by esterifying an α, β-unsaturated monocarboxylic acid and an epoxy resin and blending a radical polymerizable monomer.
Similarly, urethane (meth) acrylate resin is obtained by urethanizing an alcohol component generally composed of a polyhydric alcohol with a polyisocyanate (for example, diisocyanates) and a (meth) acrylate monomer having a hydroxyl group, and blending with a radical polymerizable monomer. It is a liquid resin obtained by. By changing the kind and ratio of each raw material, it is possible to produce a curable resin composition having physical properties suitable for various usage purposes or capable of being molded by a molding method suitable for the usage purposes. In the present invention, hereinafter, a vinyl ester or urethane (meth) acrylate having a (meth) acryloyl group may be simply referred to as “(meth) acrylate oligomer”.

  Thermosetting resins such as general unsaturated polyester resins and vinyl ester resins used for FRP (fiber reinforced plastics) contain about 30 to 60% by weight of styrene, which is a radical polymerizable monomer. Therefore, in open mold molding methods such as hand lay-up molding and spray-up molding, styrene contained in the resin is often volatilized during FRP molding and the molding work environment is often deteriorated. In recent years, with the enforcement of the PRTR (Environmental Pollutant Discharge / Transfer Registration System) Act, etc., regulations on chemical emissions have been tightened, and styrene contained in these resins has also been targeted, improving the molding work environment. Therefore, there is a demand for measures to reduce the amount of styrene volatilization for regulatory purposes.

There are roughly two methods for reducing the amount of styrene volatilized. One is to add an additive to prevent volatilization to a thermosetting resin such as unsaturated polyester resin or vinyl ester resin, to form a film of the additive on the liquid resin surface, and to volatilize styrene from the resin surface. It is a method of suppressing. In this method, a paraffin wax-based additive is used. In this method, the additive forms a film on the resin surface when the resin is allowed to stand, and the effect of suppressing the volatilization of styrene can be seen, but in the state where hand lay-up molding or spray-up molding is performed, the additive is added. The formation of the film by the agent becomes insufficient, and the effect of suppressing the volatilization of styrene is greatly reduced. In addition, the paraffin wax additive added to the resin separates on the surface of the resin while the resin is stored and placed, and in fact, when used for molding, the effect of suppressing the volatilization of styrene cannot be seen. There is also. Further, it is also affected by the working temperature to be used, and the paraffin wax-based additive may not be deposited on the resin surface, resulting in insufficient film formation.
Further, in the FRP molding operation, there is often a process (secondary bonding) in which after FRP is molded, the FRP is further molded and bonded thereon. At this time, if the above-mentioned paraffin wax-based additive is added, this secondary adhesiveness is often lowered, which causes a problem.

Another method for preventing monomer volatilization is a method in which the molecular weight of a thermosetting resin such as an unsaturated polyester resin or a vinyl ester resin is kept low, the viscosity is lowered, and the monomer blending amount is lowered (for example, styrene is reduced). .
For unsaturated polyester resins, this molecular weight reduction method is generally controlled by controlling the reaction to keep the molecular weight low, or by dicyclopentadiene modification to block the molecular ends and keep the molecular weight low (for example, patent literature). 1, refer to Patent Document 2), and a method in which a molecular end is blocked by substituting a part of polyhydric alcohol with monoalcohol to keep the molecular weight low (for example, refer to Patent Document 3). Since these methods can reduce the absolute amount of styrene contained in the unsaturated polyester resin to about 30% by weight, the instability of secondary effects of styrene, such as when using paraffin wax additives, and secondary effects Adhesiveness is not lowered, and a stable styrene suppression effect is obtained. In addition, since the viscosity can be reduced, it is possible to improve the molding workability such as the injection property and filling property of RTM molding, and when used for resin concrete, the filler can be used without impairing the molding property such as fluidity and filling property. Can be increased.

However, in the case of a method of simply controlling the molecular weight, as the unsaturated polyester resin is lowered in molecular weight, the mechanical properties such as strength and elongation of the resulting cured product are lowered, and further, the polyester end groups (hydroxyl group, carboxyl group) are reduced. Group), the water resistance of the cured product is greatly reduced.
In addition, in the case of a dicyclopentadiene-modified unsaturated polyester resin whose molecular ends are blocked using dicyclopentadiene in order to reduce the amount of hydrophilic end groups, the modified resin greatly improves the workability during FRP molding. To lower. In particular, the glass fiber mat used for FRP molding is often lost to the glass fiber mat and roving cloth, the ease of unraveling of the fiber of the glass fiber mat is often lost, and the workability of molding is greatly deteriorated. I will let you. Furthermore, this dicyclopentadiene-modified unsaturated polyester resin is often problematic because of its chemical structure and low molecular weight, which often reduce the mechanical properties such as strength and elongation of the resulting cured product.

  In the case of an unsaturated polyester resin whose end groups are blocked with monoalcohol, use of a monoalcohol having a low number of carbon atoms in the alkyl group and having a low boiling point (for example, a boiling point of 100 ° C. or lower) It is difficult to operate because it flows out together. When a monoalcohol having a large number of carbon atoms in the alkyl group and having a high boiling point is used, the esterification operation becomes easy, but in this case, the workability during FRP molding is greatly reduced. In particular, there is often a loss of familiarity with glass fiber mats and roving cloths, which are glass fiber reinforcements used for FRP molding, and the ease of unraveling of the fibers of the glass fiber mat is often lost, which greatly deteriorates the molding workability. . Furthermore, there are many problems such as lowering the mechanical properties of the cured molded article, greatly reducing the water resistance, and reducing the surface drying property of the FRP laminate. Also, when these resins are used for RTM molding or resin concrete, moldability and high filling of the filler can be achieved, but this causes a problem that the strength and water resistance of the cured product are lowered.

Even in the vinyl ester resin, the molecular weight can be reduced by minimizing the number of repeating units of the epoxy resin that is a raw material to be used, and the viscosity and the monomer content can be reduced. However, in this case as well, the surface dryability of the FRP laminated cured product may be significantly reduced by lowering the molecular weight, and there are operational problems in open molding methods such as hand lay-up molding and spray-up molding. It will be.
Radical polymerizable curable resins such as unsaturated polyester resins and vinyl ester resins with reduced radical polymerizable monomer content as described above, for example, thermosetting resins such as unsaturated polyester resins and vinyl ester resins with low styrene content Unsaturation that exhibits stable radical polymerizable monomer volatilization suppression effect (for example, low styrene volatility), is excellent in molding workability of FRP lamination, and does not cause deterioration in physical properties of the cured product. It is very difficult to produce a polyester resin. In recent years, as the work environment has been improved and the management and regulation of chemical substances have been strengthened, it has been reported that molders on the user side of unsaturated polyester resin compositions have been able to produce cured molded articles even if radical polymerizable monomer volatilization is suppressed. It has been desired to develop a curable resin composition having no deterioration in characteristics.

Japanese Unexamined Patent Publication No. 53-092888 JP 54-159492 A JP 52-003686 A

  The present invention is a curable resin composition in which the blending amount of the radical polymerizable monomer is reduced under such circumstances, thereby exhibiting a stable low radical polymerizable monomer volatility (eg, low styrene volatility) effect. In addition, although the amount of the radically polymerizable monomer is low, the FRP laminate is excellent in molding workability, and the cured molded product has a cured product having excellent mechanical properties and hot water resistance. It aims at providing the curable resin composition which has the performance which can improve the surface smoothness of laminated cured material, its manufacturing method, and the utilization method of this curable resin composition.

  As a result of intensive studies to achieve the above object, the present inventors have found that the weight average molecular weight in terms of polystyrene having an alkyl alcohol residue having at least one phenyl group and a dicyclopentadiene residue at the molecular end is 1000. A curable resin composition consisting of an unsaturated polyester of ˜3000, a (meth) acrylate oligomer having a (meth) acryloyl group at the molecular terminal and a weight average molecular weight in terms of polystyrene of 500 to 2,000, and a radical polymerizable monomer has a low viscosity. It has been found that a cured molded article having excellent physical properties can be obtained. The present invention has been completed based on such findings.

That is, the present invention
[1] (A) Unsaturated polyester having a weight-average molecular weight in terms of polystyrene of 1000 to 3000 having an alkyl alcohol residue having at least one phenyl group and a dicyclopentadiene residue at the molecular end, and (B) at the molecular end. A curable resin composition comprising a (meth) acrylate oligomer having a (meth) acryloyl group and a polystyrene-equivalent weight average molecular weight of 500 to 2000, and (C) a radical polymerizable monomer,

[2] The unsaturated polyester of component (A) is represented by the general formula (1)
R ¹ OCOCH = CHCO [OR ² OCOR ³ CO] _n OR ² OCOCH
= CHCOOR ¹ (1)
(Where R ¹ is Φ—R ⁴ —, dicyclopentadienyl group, H or —R ² OH, R ² is a polyhydric alcohol residue, and R ³ is an α, β-unsaturated polycarboxylic acid. A saturated polyvalent carboxylic acid or an aromatic polyvalent carboxylic acid residue, R ⁴ represents an alkylene group having 1 to 4 carbon atoms, Φ represents a phenyl group, and n is 0 or a positive number.)
Indicated by
The curable resin composition according to the above [1], wherein the (meth) acrylate oligomer of the component (B) is a vinyl ester and / or urethane (meth) acrylate,

[3] In the unsaturated polyester of component (A), the total amount of phenyl alcohol groups and dicyclopentadiene residues is 70 mol or more per 100 mol of terminal groups, and each of the phenyl alcohol groups is 3 mol or more, dicyclo The curable resin composition according to the above [1] or [2], which is an unsaturated polyester containing 50 mol or more of a pentadiene residue,
[3] The unsaturated polyester as component (A), wherein the unsaturated polyester contains 5 mol or more of phenyl alcohol group and 70 mol or more of dicyclopentadiene residue per 100 mol of terminal groups. ] The curable resin composition as described in the above,
[4] The unsaturated polyester of component (A) is (i) an alcohol component comprising an alkyl alcohol having one or more phenyl groups, (b) a polyhydric alcohol, and (c) dicyclopentadiene maleate and / or di-. The curable resin composition according to the above [1] or [2], which is an unsaturated polyester obtained by an esterification reaction using an acid component comprising cyclopentadiene fumarate,
[5] The curable resin composition according to any one of [1] to [4], wherein the component (B) used in the component (A) is an alkylene glycol having 3 to 6 carbon atoms having a side chain. Or the curable resin composition according to the above [4], which is an unsaturated polyester resin obtained using dialkylene glycol;
[6] The component (b) used in the component (A) is obtained by using an alcohol component in which an alkylene glycol or dialkylene glycol having 3 to 6 carbon atoms having a side chain is composed of propylene glycol or dipropylene glycol. The curable resin composition according to the above [4] or [5], which is an unsaturated polyester resin

[7] The (B) component (meth) acrylate oligomer is represented by the general formula (2)
[CH ₂ = CR ⁵ COO] _m R ⁶ (2)
(Wherein R ⁵ represents hydrogen or a methyl group, R ⁶ represents a residue of an aromatic or aliphatic epoxy compound or epoxy resin, or a compound represented by the general formula (3)
^{-R 7 OCO [NHR 8 NHCOOR 9} OCO] j NHR 8 NHCOOR 7 -
.... (3)
R ⁷ represents an alkylene group having 2 to 5 carbon atoms, R ⁸ represents an alkylene group, an aromatic or aliphatic hydrocarbon residue, R ⁹ represents a polyhydric alcohol residue, m Represents an integer of 2 or more, and j represents an integer of 0 to 5. )
The curable resin composition according to the above [1] or [2],
[8] The above [A] / (B) = 30/70 to 95/5 (weight ratio), wherein the blending ratio of the unsaturated polyester as the component (A) and the (meth) acrylate oligomer as the component (B) Curable resin composition according to any one of 1] to [7],
[9] The amount of the radically polymerizable monomer of the component (C) is 20 to 100 parts by weight with respect to 100 parts by weight of the total of the unsaturated polyester of the component (A) and the (meth) acrylate oligomer of the component (B). The curable resin composition according to the above [1],

    [10] (i) using an alkyl alcohol having one or more phenyl groups, (b) an alcohol component comprising a polyhydric alcohol, and (c) an acid component comprising dicyclopentadiene fumarate or dicyclopentadiene fumarate , An unsaturated polyester obtained by esterification reaction, having an alkyl alcohol residue having at least one phenyl group and a dicyclopentadiene residue at the molecular terminal and having a weight average molecular weight in terms of polystyrene of 1000 to 3000, ( B) A curable resin composition comprising a (meth) acryloyl group-containing (meth) acrylate oligomer having a (meth) acryloyl group and a weight average molecular weight of 500 to 2000 and (C) a radical polymerizable monomer. Manufacturing method,

[11] A radical curable resin composition in which a radical polymerization initiator is blended with the curable resin composition according to any one of [1] to [9],
[12] A resin composite composition obtained by combining the curable resin composition according to the above [11] and a fiber reinforcing material or a filler / aggregate,
[13] A laminated cured product obtained by molding and curing the radical curable resin composition or resin composite composition according to [11] or [12] above,
[14] An FRP composite material obtained by curing the radical curable resin composition or resin composite composition according to [11] or [12] above, and [15] the above [11] or [12] The present invention provides a method for producing a molded article characterized by molding and curing a radically curable resin composition or a resin composite composition.

  According to the present invention, an unsaturated polyester resin and a (meth) acrylate oligomer that can reduce the content of a radically polymerizable monomer having an alkyl alcohol residue having at least one phenyl group and a dicyclopentadiene residue at the molecular end. A curable resin composition containing, for example, a curable resin composition that can have a low styrene content, which can be expected to have a low volatility (low styrene volatility) effect of a stable radical polymerizable monomer. It is effective in improving the environment and is excellent in molding workability of FRP lamination in spite of a resin having a low monomer (for example, styrene) content. Further, a cured product having excellent mechanical properties and hot water resistance is obtained. Due to the low shrinkage, the surface smoothness of the FRP laminated cured product can be improved.

Hereinafter, the present invention will be described in more detail.
In the curable resin composition of this invention, unsaturated polyester is contained as an essential component as (A) component. This unsaturated polyester is an unsaturated polyester having an alkyl alcohol residue having at least one phenyl group and a dicyclopentadiene residue at the molecular end, and two types of end-capping groups are mixed as the unsaturated polyester. Has a molecular structure. The total of the phenyl alcohol group and the dicyclopentadiene residue is preferably 70 mol or more with respect to 100 mol of the terminal group.
In particular, in order to improve low shrinkage and surface smoothness, it is preferable to have a large number of dicyclopentadiene residues, and although not particularly specified, 50 mol of dicyclopentadiene residues per 100 mol of end groups. It is good to contain in the above range, and 70 mol or more is more preferable. The total of the phenyl alcohol group and the dicyclopentadiene residue is 80 mol or more, and each phenyl alcohol group also has an alkyl alcohol residue having at least one phenyl group as a terminal group in order to reduce viscosity. It is good to contain in 3 mol or more with respect to 100 mol, and also 5 mol or more is more preferable.
The unsaturated polyester of component (A) is composed of an unsaturated polyester having a dicyclopentadiene residue at the molecular end and an unsaturated polyester having an alkyl alcohol residue having at least one phenyl group at the molecular end. It is also possible to synthesize and mix them so that the ratio is as described above, or to manufacture them.

  In order to obtain an unsaturated polyester having an alkyl alcohol residue having at least one phenyl group at the molecular end, an alkyl alcohol having at least one phenyl group as the component (a) is used as a raw material. More preferably, an alkyl group having 1 to 4 carbon atoms is used. By using these alcohol components, it is possible to reduce the viscosity of the resulting unsaturated polyester resin and to reduce the amount of radical polymerizable monomer, and when FRP is used, the workability at the time of laminating work is not lowered, and the water resistance is further improved. -Decrease in physical properties of cured products can be suppressed. When the carbon number of the alkyl group is 5 or more, it becomes close to the case where a long-chain alkyl monoalcohol is used, and the obtained cured product may become too soft, or the water resistance and the cured product properties may be deteriorated.

  Examples of alkyl alcohols having one or more phenyl groups as component (a) include commercially available phenyls having 1 to 4 carbon atoms in alkyl groups such as benzyl alcohol (phenylmethanol), phenylethanol, phenylpropanol, and phenylbutanol. Examples include alkyl alcohols. In particular, benzyl alcohol having a small number of carbon atoms in the alkyl group is more preferable in order to improve the workability during the FRP laminating operation.

  In order to obtain an unsaturated polyester having a dicyclopentadiene residue at the molecular end, (c) an acid component comprising dicyclopentadiene fumarate and / or dicyclopentadiene fumarate is used as an essential component. (C) By using an acid component consisting of the component dicyclopentadiene fumarate and / or dicyclopentadiene fumarate, it becomes possible to reduce the viscosity of the unsaturated polyester resin obtained and to reduce the radical polymerizable monomer, and The water resistance and surface dryness of the cured product can be improved. Further, the shrinkage of curing can be reduced, and an FRP molded product having improved surface smoothness can be obtained.

  (C) The component dicyclopentadiene maleate or dicyclopentadiene fumarate is prepared by, for example, reacting maleic anhydride and water at 50 ° C. to 100 ° C. to synthesize maleic acid, and further adding dicyclopentadiene to 120 ° C. to It can be synthesized by reacting at 140 ° C. The component (c) synthesized by such a procedure can be used as a raw material for the unsaturated polyester as the component (A) of the curable resin composition of the present invention. Further, dicyclopentadiene fumarate or dicyclopentadiene fumarate obtained by reacting hydroxydicyclopentadiene with maleic anhydride, maleic acid or fumaric acid can also be used. In addition, following the above synthesis method, the (A) component alcohol component, the (B) component polyhydric alcohol component, and the (E) component acid component are added to synthesize the (A) component unsaturated polyester of the present invention. You can also take a way.

  In the curable resin composition of the present invention, an alcohol component composed of (b) a polyhydric alcohol is used as a raw material for the unsaturated polyester as the component (A). In order to reduce the viscosity of the curable resin composition and reduce the radical polymerizable monomer and to reduce the curing shrinkage of the cured product, (b) the alcohol component composed of a polyhydric alcohol is a methyl group or the like. It is preferable to use a component containing propylene glycol or dipropylene glycol, more preferably an alkylene glycol or dialkylene glycol having 3 to 6 carbon atoms having a side chain. The amount used is (b) 50 mol% or more, preferably 70 mol% or more, more preferably 100 mol%, when the total number of moles of polyhydric alcohol is 100 mol. If it is less than 50 mol%, it may not be possible to achieve both lowering the viscosity and reducing the polymerizable monomer and reducing the curing shrinkage of the cured product.

  Furthermore, the use molar ratio of propylene glycol (PG) and dipropylene glycol (DPG) is PG / DPG = 20/80 to 80/20, more preferably PG / DPG = 40/60 to 60/40. To do. If the amount of dipropylene glycol increases, the reduction in the curing shrinkage of the cured product may be insufficient. If the amount of propylene glycol exceeds this ratio, the viscosity of the resin liquid is lowered (particularly under low temperature conditions) and the polymerizable monomer. Reduction may be insufficient. (B) The alcohol component consisting of the polyhydric alcohol of component (A) may be used together when synthesizing the unsaturated polyester of component (A), or the unsaturated polyester used separately is synthesized and then mixed. May be.

  Examples of the alkylene glycol or dialkylene glycol having 3 to 6 carbon atoms having a side difference such as a methyl group include propylene glycol, dipropylene glycol, 2-methyl-1,3-propanediol, 1,2-butanediol, 1,3-butanediol, 2,3-butanediol, 1,5-pentanediol, 3-methyl-1,5-pentanediol, 2,2-dimethyl-1,3-propanediol (neopentyl glycol), etc. Is mentioned. Examples of polyhydric alcohols that can be used other than these include ethylene glycol, diethylene glycol, 1,4-butanediol, 1,6-hexanediol, methyloctanediol, nonanediol, 1,4-cyclohexanediol, 1, Examples include commercially available polyhydric alcohols such as 4-cyclohexanedimethanol, polyethylene glycol, polypropylene glycol, polytetramethylene glycol, glycerin, trimethylolethane, trimethylolpropane, pentaerythritol, dipentaerythritol, and the effect of the present invention is impaired. Can be used in a range that does not exist.

  Furthermore, in addition to the above, commercially available 2 such as propylene oxide adducts such as bisphenol A, bisphenol F, bisphenol S, or ethylene oxide adducts, or 2,2-di (4-hydroxycyclohexyl) propane [hydrogenated bisphenol A]. And monohydric alcohols. Furthermore, what decompose | degraded PET (polyethylene phthalate), PBT (polybutylene phthalate), PEN (polyethylene naphthalate), etc. with glycol etc. can also be utilized. One of these may be selected and used, or two or more of these may be used in combination.

  In particular, in order not to lower the water resistance, it is preferable to use those having a side chain such as a methyl group or an ethyl group, those having a cyclic structure such as cyclohexane, and those having a bisphenol skeleton. Furthermore, in order to reduce the shrinkage rate and improve the surface smoothness, it is preferable to use one having a cyclic structure such as a cyclohexane ring or one having a bisphenol skeleton.

  In the curable resin composition of the present invention, the unsaturated polyester of component (A) is an (e) polyvalent carboxylic acid component, α, β-unsaturated polyvalent carboxylic acid, saturated polyvalent carboxylic acid, aromatic polyvalent carboxylic acid component. Carboxylic acid and reactive derivatives thereof are used as necessary. Examples of the α, β-unsaturated polyvalent carboxylic acid include maleic acid, fumaric acid, itaconic acid, citraconic acid, chloromaleic acid and the like. Examples of these reactive derivatives include acid anhydrides such as maleic anhydride, itaconic anhydride and chloromaleic anhydride, and lower alkyl esters of the above unsaturated polycarboxylic acids. One of these may be selected and used, or two or more of these may be used in combination.

  Examples of saturated polyvalent carboxylic acids include succinic acid, adipic acid, sebacic acid, tetrahydrophthalic acid, endomethylenetetrahydrophthalic acid, and the like. Examples of aromatic polyvalent carboxylic acids include orthophthalic acid, isophthalic acid, Examples include terephthalic acid, naphthalenedicarboxylic acid, chlorendic acid (hett acid), halogenated phthalic acid such as tetrabromophthalic acid, trimellitic acid, and pyromellitic acid. Examples of these reactive derivatives include phthalic anhydride, succinic anhydride, tetrahydrophthalic anhydride, chlorendic anhydride, endomethylenetetrahydrophthalic anhydride, tetrabromophthalic anhydride, trimellitic anhydride, pyromellitic anhydride And the above-mentioned saturated polycarboxylic acids such as dimethyl phthalate, diethyl phthalate, dimethyl isophthalate, and dimethyl terephthalate, and lower alkyl esters of aromatic polycarboxylic acids. These saturated polyvalent carboxylic acids, aromatic polyvalent carboxylic acids, and reactive derivatives thereof may be used by selecting one of them, or two or more of them may be used in combination. Good.

  In the curable resin composition of the present invention, in the unsaturated polyester of the component (A), the component (a), the alcohol component (b), the component (c) and the component (e) are added if necessary. It can be produced by condensation polymerization of the acid component. Although not particularly specified, the ratio of the alcohol component to the acid component is a ratio of hydroxyl group (OH) / carboxyl group (COOH) = 0.90 to 1.30, more preferably 1.00 to 1.20. The reaction is carried out at a ratio of

The ratio of (i) phenylalkyl alcohol component / (c) dicyclopentadiene residue component to be a molecular end group is 5/95 to 30/70 (mol%). If the ratio is out of the range, it may not be possible to achieve both lowering the viscosity and reducing the polymerizable monomer and reducing the cure shrinkage of the cured product.
In addition, the α, β-unsaturated carboxylic acid component in the component (e) is used in an amount equal to or greater than the molar ratio of the component (a). This is for introducing an unsaturated group as close as possible to the molecular end, thereby improving the physical properties.

In the curable resin composition of the present invention, the esterification reaction of the unsaturated polyester of the component (A) is performed at a temperature of 160 to 230 ° C. in an inert gas stream such as nitrogen according to a conventional method, and under pressure or It can be synthesized by esterification to a required stage under reduced pressure.
In the curable resin composition of the present invention, the synthesis reaction of the unsaturated polyester of component (A) is preferably performed by a two-stage or three-stage reaction method. In conducting the three-stage reaction, first, maleic anhydride and water are reacted in the first stage reaction to synthesize maleic acid, and dicyclopentadiene is added to add (c) component dicyclopentadiene maleate or fumarate. Synthesize. Next, (i) phenylalkyl alcohol component and (e) carboxylic acid component are charged and esterified, and then (b) polyhydric alcohol component and additional (e) carboxylic acid component are added if necessary. To do. When the synthesized (c) dicyclopentadiene component is used, (b) a phenylalkyl alcohol component and (e) a carboxylic acid component are first esterified and then the remaining ones are reacted. Can be synthesized. By synthesizing with these methods, unsaturated groups can be efficiently introduced near the molecular ends, and the cured product can form cross-linking points near the molecular ends to make the molecular chains function more effectively. Decrease in physical properties due to molecular weight can be prevented.

In the curable resin composition of the present invention, the unsaturated polyester as the component (A) is represented by the general formula (1).
R ¹ OCOCH = CHCO [OR ² OCOR ³ CO] _n OR ² OCOCH = CHCOOR ¹
(1)
(Wherein, R ¹ is [Phi-R ⁴ -, dicyclopentadienyl group, a hydrogen or -R ² OH, R ³ is alpha, beta-unsaturated carboxylic acids, alpha, beta-unsaturated polycarboxylic acid, (Saturated polyvalent carboxylic acid or aromatic polyvalent carboxylic acid, R ⁴ represents an alkylene group having 1 to 4 carbon atoms, Φ represents a phenyl group, and n is 0 or a positive number.)
It has a chemical structure as shown in FIG.

  In this way, it has a molecular structure having an alkyl alcohol residue structure and a dicyclopentadiene residue structure having one or more phenyl groups at the molecular terminal, so that it not only has a low viscosity, but also contains a radical polymerizable monomer content. Even if the resin content is reduced, the viscosity of the resin can be lowered, and even if the content of the radical polymerizable monomer is reduced, the molding workability at the time of FRP lamination can be improved. Moreover, since an unsaturated group can be introduced near the molecular end of the unsaturated polyester, it is possible to prevent deterioration in physical properties due to the lower molecular weight of the resin composition.

  In the curable resin composition of the present invention, the unsaturated polyester of the component (A) can be a resin with a low content of the radical polymerizable monomer, so that the viscosity increase of the liquid resin can be suppressed. The unsaturated polyester is reduced in molecular weight, and the polystyrene-equivalent weight average molecular weight is in the range of 1000 to 3000. If the molecular weight is smaller than this range, it is difficult to avoid a decrease in mechanical properties of the cured product. If the molecular weight is larger than this range, the resin viscosity will increase, leading to an increase in the amount of radically polymerizable monomer, and the effect of reducing the volatility of the radically polymerizable monomer will not be obtained.

In the curable resin composition of the present invention, as the component (B), a (meth) acrylate oligomer having a (meth) acryloyl group at the molecular end is used as an essential component.
The (B) component (meth) acrylate oligomer is preferably a vinyl ester having a highly polar hydroxyl group (OH) or urethane bond (—O—CO—NH—) in the molecular chain, or urethane (meth) acrylate. FRP molding workability (particularly molding using a glass mat) when these (meth) acrylate oligomers are blended into the curable resin composition of the present invention to give a resin with a low radical polymerizable monomer content. In operation) and mechanical properties can be further improved.

In the curable resin composition of the present invention, the vinyl ester used as the component (B) is produced by a known method and esterifies an epoxy resin and an α, β-unsaturated monocarboxylic acid. It is the epoxy (meth) acrylate obtained by this.
Examples of the epoxy resin used include diglycidyl ether compounds of bisphenol A, bisphenol AD, bisphenol F or bisphenol S or high molecular weight homologues thereof, phenol novolac type polyglycidyl ether or cresol novolac type polyglycidyl ethers, etc. Is mentioned. Furthermore, these halogenated derivatives can also be used. Further, in the synthesis process, aromatic epoxy resins obtained by reacting phenols such as bisphenol A, bisphenol AD, bisphenol F, and bisphenol S with these glycidyl ethers, and aliphatic epoxy resins may also be used. good.

  Examples of α, β-unsaturated monocarboxylic acids used in vinyl esters are more commonly acrylic acid and methacrylic acid, but besides these, α, β- such as crotonic acid, tiglic acid, cinnamic acid, and the like. An unsaturated monocarboxylic acid, an unsaturated monocarboxylic acid derived from an unsaturated monocarboxylic acid, acrylic acid or methacrylic acid can be used within the range where there is no problem.

The vinyl ester is a mixture of the above glycidyl ethers of phenols and α, β-unsaturated monocarboxylic acid in a ratio of carboxyl group / epoxy group = 1.00 to 1.05, in a temperature range of 80 ° C. to 140 ° C. It can be synthesized by esterification. Furthermore, a reaction catalyst can be used if necessary.
Examples of the catalyst include tertiary amines such as benzyldimethylamine, triethylamine, N, N-dimethylaniline, triethylenediamine, 2,4,6-tris (dimethylaminomethyl) phenol, and quaternary such as trimethylbenzylammonium chloride. Examples thereof include metal salts such as ammonium salt and lithium chloride.

In addition to the vinyl ester composed of the above-mentioned epoxy (meth) acrylate, α, β- having a terminal carboxyl group saturated polyester or unsaturated polyester obtained from a saturated dicarboxylic acid or unsaturated dicarboxylic acid and a polyhydric alcohol, and an epoxy group Α, β having an epoxy group and a saturated polyester obtained by reacting an unsaturated carboxylic acid derivative or polyester (meth) acrylate of an unsaturated polyester, or phenols such as bisphenol A, bisphenol AD, bisphenol F, and bisphenol S -Vinyl esters obtained by reacting unsaturated carboxylic acid derivatives can also be used.
Examples of the α, β-unsaturated carboxylic acid derivative having an epoxy group used include glycidyl acrylate and glycidyl methacrylate. Examples of the saturated dicarboxylic acid or unsaturated dicarboxylic acid and polyhydric alcohol used in them include dicarboxylic acids described as (e) component which is a raw material component of the unsaturated polyester, (b) ) And the like, and examples of phenols include bisphenol A, bisphenol AD, bisphenol F, bisphenol S, phenol novolac, and cresol novolac.

In the curable resin composition of the present invention, the urethane (meth) acrylate used as the component (B) is produced by a known method and has a polyisocyanate, a polyhydric alcohol, and a hydroxyl group (meta ) It can be synthesized by urethanizing an acrylate monomer.
Examples of polyisocyanates used include 2,4- and 2,6-tolylene diisocyanate, 4,4'-diphenylmethane diisocyanate, xylylene diisocyanate, tetramethylxylylene diisocyanate, hexamethylene diisocyanate, 4, 4 Examples thereof include diisocyanates such as' -dicyclohexylmethane diisocyanate, isophorone diisocyanate, naphthalene diisocyanate, phenylene diisocyanate, cyclohexyldimethylene diisocyanate, and these derivatives can also be used.

Examples of the (meth) acrylate monomer having a hydroxyl group include 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, 2-hydroxypropyl acrylate, 2-hydroxypropyl methacrylate, hydroxybutyl acrylate, and hydroxybutyl methacrylate.
Examples of the polyhydric alcohol include those similar to the examples of the (b) polyhydric alcohol component which is a raw material component of the unsaturated polyester of the component (A).
Urethane (meth) acrylate has a ratio of hydroxyl group / isocyanate group = 1.00 to 1.05, urethanation reaction of polyisocyanate and polyhydric alcohol at 50 to 100 ° C., and subsequently has a hydroxyl group ( It can be synthesized by urethanizing a (meth) acrylate monomer.
Furthermore, a reaction catalyst can be used if necessary. Examples of the catalyst include organic tin compounds and amines. In order to obtain a resin having a lower viscosity, it is preferable to reduce the number of repeating units of the molecular chain by reducing the amount of polyhydric alcohol used or not using it.

  In the curable resin composition of the present invention, as the (B) (meth) acrylate oligomer component, polyester (meth) acrylate can be used in a range without any problem. This polyester (meth) acrylate can be obtained, for example, by synthesizing a terminal hydroxyl group type saturated polyester or unsaturated polyester and esterifying acrylic acid or methacrylic acid.

  In the curable resin composition of the present invention, the (meth) acrylate oligomer having a (meth) acryloyl group at the molecular end of the component (B) is a resin with a low content of radical polymerizable monomer. The molecular weight is lowered, and the resulting liquid resin has a prescription in which the increase in viscosity is suppressed. The molecular weight is a polystyrene equivalent weight average molecular weight of 500-2000. When the molecular weight is larger than this range, it is necessary to increase the blending ratio of the radical polymerizable monomer. If the molecular weight is lower than this range, the resulting cured product has poor physical properties.

  As the (meth) acrylate oligomer having a (meth) acryloyl group at the molecular end of the component (B), vinyl ester and urethane (meth) acrylate may be used alone, or two or more of these may be used in combination. Also good. In order to improve the shrinkage of the cured product and the surface smoothness, it is more preferable to use urethane (meth) acrylate. In order to lower the viscosity of the resin, it is preferable to use a vinyl ester.

In the curable resin composition of the present invention, the (meth) acrylate oligomer having a (meth) acryloyl group at the molecular terminal used as the component (B) is represented by the general formula (2).
[CH ₂ = CR ⁵ COO] _m R ⁶ (2)
(Wherein R ⁵ represents hydrogen or a methyl group, and R ⁶ represents a residue of an aromatic or aliphatic epoxy compound or epoxy resin. Here, an aromatic or aliphatic epoxy compound or epoxy resin) Is a diglycidyl ether compound such as bisphenol A, bisphenol AD, bisphenol F, bisphenol S, or a high molecular weight homologue thereof, phenol novolac polyglycidyl ether or cresol novolac polyglycidyl ether, or an epoxy comprising these halogenated derivatives. Resin or general formula (3)
^{-R 7 OCO [NHR 8 NHCOOR 9} OCO] j NHR 8 NHCOOR 7 -
.... (3)
R ⁷ represents an alkylene group having 2 to 5 carbon atoms, R ⁸ represents an alkylene group obtained by removing an isocyanate group from a diisocyanate compound, a residue of an aromatic or aliphatic hydrocarbon, and R ⁹ represents Represents a polyhydric alcohol residue, m represents an integer of 2 or more, and j represents an integer of 0 to 5; )
It has the structure shown by.

  Since these vinyl esters and urethane (meth) acrylates have the molecular skeleton described above, they have excellent hot water resistance and mechanical properties even if they have a low molecular weight in order to reduce the radical polymerizable monomer content. In the case of only the component (A) even if the content of the radically polymerizable monomer is lowered, since the physical properties can be further improved than the resin in the case of only the resin, and the molecular skeleton has polar groups such as hydroxyl groups and urethane bonds. The laminating workability at the time of FRP molding could be further improved than the above resin.

  In the curable resin composition of this invention, a radically polymerizable monomer is mix | blended as (C) component. Examples of radically polymerizable monomers include styrene, α-methylstyrene, vinyltoluene, chlorostyrene, dichlorostyrene, t-butylstyrene, divinylbenzene, and styrene α-, o-, m-, p-alkyl, Styrenic monomers such as nitro-, cyano-, amide-, ester-derivatives and vinylnaphthalene; vinyl compounds such as ethyl vinyl ether and methyl vinyl ketone; dienes such as butadiene, 2,3-dimethylbutadiene, isoprene and chloroprene; (Meth) acrylic acid methyl, (meth) acrylic acid ethyl, (meth) acrylic acid-n-propyl, (meth) acrylic acid-i-propyl, (meth) acrylic acid-n-butyl, (meth) acrylic acid-sec -Butyl, (meth) acrylic acid-ter-butyl, (meth) acrylic Pentyl laurate, neopentyl (meth) acrylate, isoamyl (meth) acrylate, hexyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, lauryl (meth) acrylate, dodecyl (meth) acrylate, (meth ) Cyclopentyl acrylate, cyclohexyl (meth) acrylate, 2-methylcyclohexyl (meth) acrylate, dicyclohexyl (meth) acrylate, isobornyl (meth) acrylate, adamantyl (meth) acrylate, allyl (meth) acrylate, Promethyl (meth) acrylate, phenyl (meth) acrylate, naphthyl (meth) acrylate, anthracenyl (meth) acrylate, anthraninonyl (meth) acrylate, piperonyl (meth) acrylate, salicyl (meth) acrylate , (Meta) acrylic Acid furyl, furfuryl (meth) acrylate, tetrahydrofuryl (meth) acrylate, pyranyl (meth) acrylate, benzyl (meth) acrylate, phenethyl (meth) acrylate, cresyl (meth) acrylate, (meth) acrylic Acid-1,1,1-trifluoroethyl, perfluoroethyl (meth) acrylate, perfluoro-n-propyl (meth) acrylate, perfluoro-i-propyl (meth) acrylate, (meth) acryl Triphenylmethyl acid, cumyl (meth) acrylate, 3- (N, N-dimethylamino) propyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate (Meth) acrylic acid esters such as: diethyl citraconic acid, diethyl maleate, fumar Diethyl, and unsaturated dicarboxylic acid diester of itaconic acid diethyl, and the like.

  Moreover, you may use the (meth) acrylic acid ester compound which has two or more (meth) acryloyl groups in a molecule | numerator, and a well-known thing can be used. Examples thereof include ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, triethylene glycol di (meth) acrylate, polyethylene glycol di (meth) acrylate, 1,4-butanediol di (meth) acrylate, 1 , 6-hexanediol di (meth) acrylate, 1,9-nonanediol di (meth) acrylate, neopentyl glycol di (meth) acrylate, glycerin di (meth) acrylate, 2-hydroxy-3-acryloyloxypropyl ( Examples include (meth) acrylic acid esters of various glycols such as (meth) acrylate, trimethylolpropane tri (meth) acrylate, diallyl phthalate, diallyl terephthalate, diallyl succinate, triary Allyl compounds and oligomers thereof such as cyanurate and the like. Without being limited thereto, monomers and oligomers having radically polymerizable unsaturated groups can also be used, and non-reactive diluents can be used in combination as long as the characteristics are not impaired.

  Non-reactive diluents include organic solvents. These radically polymerizable monomers may be used alone or in combination of two or more. In general, styrene is preferably used. In order to more effectively suppress the volatilization of the radical polymerizable monomer, it is preferable to selectively use a radical polymerizable monomer having a higher boiling point.

  As the blending amount of the radical polymerizable monomer in the curable resin composition of the present invention, the suitable blending ratio varies depending on the use mode, the purpose of use, etc., but generally 20 parts per 100 parts by weight of unsaturated polyester or vinyl ester. It is in the range of ˜100 parts by weight. However, in open mold molding methods such as hand lay-up molding and spray-up molding, it is possible to reduce the volatility of the radical polymerizable monomer, to keep the curing shrinkage rate low, and to the resin that can not lower the molding workability. In order to do this, it is preferable to blend the radical polymerizable monomer in the range of 30 to 60 parts by weight per 100 parts by weight of the total of the unsaturated polyester and the (meth) acrylate oligomer.

  The curable resin composition of the present invention is a resin composition in which (A) component unsaturated polyester, (B) component (meth) acrylate oligomer, and (C) component radical polymerizable monomer are blended. The blending ratio of the component (A) / component (B) is usually 30/70 to 95/5 parts by weight, although the suitable blending ratio varies depending on the use mode, purpose of use and the like. In particular, in order to reduce the shrinkage rate and improve the surface smoothness, it is preferably blended at 70/30 to 95/5 parts by weight. Further, in order to further improve the hot water resistance and mechanical properties, it is preferably blended at 30/70 parts by weight to 70/30 parts by weight.

  If desired, a polymerization inhibitor is added to the curable resin composition of the present invention. As this polymerization inhibitor, those conventionally used for unsaturated polyester resins and vinyl ester resins, for example, hydroquinones such as hydroquinone, methylhydroquinone, trimethylhydroquinone, t-butylhydroquinone, catechol, t-butylcatechol, Examples include quinones such as P-benzoquinone, naphthoquinone, and tolquinone, and phenols such as 2,6-di-t-butyl-4-methylphenol, t-butyl-paracresol, and hydroquinone monomethyl ether.

  The curable resin composition of the present invention can be easily cured by room temperature curing or heat curing by adding a curing agent and a curing accelerator commonly used in ordinary unsaturated polyester resins and vinyl ester resins. Examples of the curing agent include methyl ethyl ketone peroxide, acetylacetone peroxide, cyclohexanone peroxide, t-butylperoxybenzoate, t-butylperoxypivalate, t-butylperoxy-2-ethylhexanoate, and benzoylperoxide. Organic peroxides such as oxide, dicumyl peroxide, cumene hydroperoxide and the like can be mentioned.

  On the other hand, examples of curing accelerators include organic acid salts of cobalt such as cobalt naphthenate and cobalt octylate, organic acid salts such as calcium, potassium, barium, manganese and vanadium, N, N-dimethylaniline, N, Commonly used for unsaturated polyester resins such as N-diethylaniline, N, N-dimethyl-P-toluidine, N, N-dimethylacetoacetamide, acetylacetone, acetylbutyrolactone, methyl acetoacetate, ethyl acetoacetate, and vinyl ester resins What is being done is mentioned.

A resin composite composition can be obtained by using the curable resin composition of the present invention in combination with a fiber reinforcing material or a filler / aggregate. By molding and curing these resin composite compositions, an FRP laminate coated with a gel coat and having improved surface smoothness can be produced.
Examples of the fiber reinforcing material used in combination include organic or inorganic and synthetic or natural fiber reinforcing materials such as glass fiber, carbon fiber, polyester fiber, aramid fiber, and vinylon fiber. As for the shape, chops, chopped strand mats, continuous strand mats, rovings, roving cloths, cloths such as plain weave, satin weave, twill weave, woven fabrics, braids, three-dimensional woven fabrics, braids, and the like can be used. The amount of the fiber reinforcing material used is 10 to 200 parts by weight with respect to 100 parts by weight of the curable resin composition.

  Examples of the filler used in combination include calcium carbonate, aluminum hydroxide, fly ash, barium sulfate, talc, clay, glass powder, and wood powder. Furthermore, glass microballoons, saran resin microballoons, and acrylonitrile. And hollow fillers such as microballoons and shirasu balloons. Examples of aggregates include general aggregates such as quartz sand, crushed stone, and gravel, and synthetic aggregates synthesized from incinerated ash, lightweight aggregates, and the like. For mortar use, those having a particle size of about 5 mm or less are preferred. The amount of filler / aggregate used is 10 to 500 parts by weight per 100 parts by weight of the curable resin composition.

Further, when a resin composition for lamination is used, a thixotropic agent or the like is added to prevent the resin from dripping. Specific examples of the thixotropic agent include anhydrous fine powder silica, asbestos, clay and the like. As the thixotropic agent, specifically, polyethylene glycol, glycerin, polyhydroxycarboxylic acid amide, organic quaternary ammonium salt, BYK-R-605 (trade name; manufactured by Big Chemie Japan Co., Ltd.), etc. Is mentioned.
Furthermore, various additives such as a pigment, a release agent, an antioxidant, an ultraviolet absorber, an impregnation agent, and an antifoaming agent can be blended if necessary within a range that does not impair the object of the present invention. Further, if necessary, a thermoplastic resin such as polystyrene, polyvinyl acetate, polybutadiene, styrene-vinyl acetate copolymer, and saturated polyester can be appropriately blended for suppressing shrinkage.

  Applications in which the curable resin composition and the resin composite composition of the present invention are used include FRPs that require surface smoothness such as boats, ships, housing equipment (tubs, septic tanks, water-related products, etc.), automobile vehicle parts, etc. It is very suitable for the use of laminated molded products. Also, there are uses for cured products such as resin concrete and resin mortar. Specific products include pipe products, manholes, water collection masses, lids and other water and sewage-related materials, and information and communication related boxes. Is mentioned. Other applications include gel coating, paints, adhesives, decorative plates, tank containers, electrical and electronic parts, civil engineering materials, and molding materials such as BMC (Bulk Molding Compound) and SMC (Sheet Molding Compound). It is done.

  Methods for molding products for the above applications include hand lay-up molding, spray-up molding, and filament winding molding, resin injection molding and resin transfer molding, and vacuum assist resin injection (VARI) molding. Closed molding methods such as a resin injection vacuum molding method, a pultrusion molding method, a vacuum molding method, a pressure molding method, a compression molding method, an injection molding method, a casting method, and a spray method can be applied.

Next, the present invention will be described in more detail than examples, but the present invention is not limited to these examples.
<Resin synthesis>
<Synthesis of unsaturated polyester resin>

(Synthesis Example 1)
A 5-liter flask equipped with a stirrer, distillation condenser, thermometer, and nitrogen inlet tube was charged with 1820 g of dicyclopentadiene and 250 g of water, and exothermic reaction of 1321 g of maleic anhydride from 60 ° C. was conducted while stirring under a nitrogen stream. In addition, the reaction was carried out in four portions, followed by reaction at 130 ° C. for 2 hours to synthesize dicyclopentadiene maleate and dicyclopentadiene fumarate, and subsequently charged with 82 g of benzyl alcohol and 70 g of maleic anhydride, The mixture was allowed to react for 1 hour while paying attention to heat generation at 100 ° C., and further charged with 302 g of propylene glycol and 457 g of dipropylene glycol. When it reaches 5 mgKOH / g, it is cooled and unsaturated poly 4000 g of ester was obtained. As a result of measuring the molecular weight of this polyester by GPC, the weight average molecular weight in terms of polystyrene was 1890, and as a result of measuring the hydroxyl value, it was 10.5 mgKOH / g.
Next, 0.50 g of hydroquinone was added to 4000 g of this unsaturated polyester, and dissolved in 1000 g of styrene to prepare an unsaturated polyester resin (PE-1). The viscosity (25 ° C.) of this resin (PE-1) was 16.2 dPa · s.

(Synthesis Example 2)
In the same manner as in Synthesis Example 1, 1731 g of dicyclopentadiene and 236 g of water were charged, and 1258 g of maleic anhydride was added in four portions while being heated and stirred under a nitrogen stream while paying attention to an exothermic reaction. The mixture was reacted at 2 ° C. for 2 hours to synthesize dicyclopentadiene fumarate and dicyclopentadiene fumarate, and further charged with 113 g of benzyl alcohol and 102 g of maleic anhydride, and subjected to esterification at 100 ° C. while paying attention to heat generation. Propylene glycol (148 g) and dipropylene glycol (707 g) were charged, and esterification was carried out according to the same procedure. When the acid value reached 28.9 mgKOH / g, the mixture was cooled to obtain 4000 g of unsaturated polyester. As a result of measuring the molecular weight of this polyester by GPC, the polystyrene-reduced molecular weight was 2120 as a weight average molecular weight, and as a result of measuring the hydroxyl value, it was 11.1 mgKOH / g.
Next, 0.50 g of hydroquinone was added to 4000 g of this unsaturated polyester and dissolved in 1000 g of styrene to prepare an unsaturated polyester resin (PE-2) having a viscosity (25 ° C.) of 13.3 dPa · s.

(Synthesis Example 3)
In the same manner as in Synthesis Example 1, 1820 g of dicyclopentadiene and 248 g of water were charged, and 1322 g of maleic anhydride was added in 4 portions while paying attention to exothermic reaction while heating and stirring under a nitrogen stream. Then, dicyclopentadiene fumarate and dicyclopentadiene fumarate were synthesized by reacting at 2 ° C. for 2 hours. Further, 162 g of benzyl alcohol and 147 g of maleic anhydride were added, and the esterification reaction was carried out at 100 ° C. while paying attention to heat generation. 616 g of propylene glycol was charged, and esterification was carried out according to the same procedure. When the acid value reached 25.2 mgKOH / g, the mixture was cooled to obtain 4000 g of unsaturated polyester. As a result of measuring the molecular weight of this polyester by GPC, the molecular weight in terms of polystyrene was a weight average molecular weight of 1880, and as a result of measuring the hydroxyl value, it was 9.9 mgKOH / g.
Next, 0.50 g of hydroquinone was added to 4000 g of this unsaturated polyester, and dissolved in 1000 g of styrene to prepare an unsaturated polyester resin (PE-3) having a viscosity (25 ° C.) of 17.6 dPa · s.

(Synthesis Example 4)
In the same manner as in Synthesis Example 1, 1645 g of dicyclopentadiene and 225 g of water were charged, and 1195 g of maleic anhydride was added in four portions while being heated and stirred under a nitrogen stream while paying attention to an exothermic reaction. Then, dicyclopentadiene fumarate and dicyclopentadiene fumarate were synthesized by reacting at 2 ° C. for 2 hours. Further, 146 g of benzyl alcohol and 133 g of maleic anhydride were added, and the esterification reaction was performed at 100 ° C. while paying attention to heat generation. Dipropylene glycol (945 g) was charged and subjected to esterification reaction according to the same procedure. When the acid value reached 23.7 mgKOH / g, the mixture was cooled to obtain 4000 g of unsaturated polyester. As a result of measuring the molecular weight of this polyester by GPC, the molecular weight in terms of polystyrene was a weight average molecular weight of 1970, and as a result of measuring the hydroxyl value, it was 16.8 mgKOH / g. Next, 0.50 g of hydroquinone was added to 4000 g of this unsaturated polyester and dissolved in 1000 g of styrene to prepare an unsaturated polyester resin (PE-4) having a viscosity (25 ° C.) of 10.0 dPa · s.

<Synthesis of general-purpose unsaturated polyester resin (comparative synthesis example)>
(Synthesis Example 5)
In the same manner as in Synthesis Example 1, 2007 g of dicyclopentadiene and 274 g of water were charged, and 1420 g of maleic anhydride was added in four portions while being heated and stirred under a nitrogen stream while paying attention to an exothermic reaction. The reaction was carried out at 2 ° C. for 2 hours to synthesize dicyclopentadiene fumarate and dicyclopentadiene fumarate, further charged with 573 g of propylene glycol, and the esterification reaction was carried out in the same procedure
When the acid value reached 26.4 mgKOH / g, the mixture was cooled to obtain 4000 g of unsaturated polyester. As a result of measuring the molecular weight of this polyester by GPC, the weight average molecular weight in terms of polystyrene was 1310, and as a result of measuring the hydroxyl value, it was 12.9 mgKOH / g.
Next, 0.50 g of hydroquinone was added to 4000 g of this unsaturated polyester and dissolved in 1000 g of styrene to prepare an unsaturated polyester resin (PE-5) having a viscosity (25 ° C.) of 18.3 dPa · s.

(Synthesis Example 6)
In the same manner as in Synthesis Example 1, 1337 g of maleic anhydride and 1047 g of benzyl alcohol were added, and the esterification reaction was performed at 100 ° C. while paying attention to heat generation. Further, 1150 g of propylene glycol and 861 g of phthalic anhydride were added. The esterification reaction was performed, and when the acid value reached 25.0 mgKOH / g, the mixture was cooled to obtain 4000 g of unsaturated polyester. As a result of measuring the molecular weight of this polyester by GPC, the weight average molecular weight in terms of polystyrene was 1710, and as a result of measuring the hydroxyl value, it was 49.5 mgKOH / g.
Next, 0.50 g of hydroquinone was added to 4000 g of this unsaturated polyester and dissolved in 1000 g of styrene to prepare an unsaturated polyester resin (PE-6) having a viscosity (25 ° C.) of 5.4 dPa · s.

(Synthesis Example 7)
In the same manner as in Synthesis Example 1, 1472 g of propylene glycol, 1637 g of phthalic anhydride, and 723 g of maleic anhydride were charged and subjected to esterification to obtain 3500 g of an unsaturated polyester having an acid value of 38.5 mgKOH / g and a weight average molecular weight of 3200. . As a result of measuring the molecular weight of this polyester by GPC, the polystyrene-reduced molecular weight was 3200 in terms of weight average molecular weight, and the hydroxyl value was measured to be 45.2 mgKOH / g.
Hydroquinone 0.50 g was added to 3500 g of this unsaturated polyester and dissolved in 1500 g of styrene to prepare an unsaturated polyester resin (PE-7) having a viscosity (25 ° C.) of 14.2 dPa · s.

(Synthesis Example 8)
In the same manner as in Synthesis Example 1, 2077 g of propylene glycol, 899 g of phthalic anhydride, and 1388 g of maleic anhydride were charged in the one-step reaction method, and the esterification reaction was carried out to obtain an acid value of 32.5 mgKOH / g and a weight average molecular weight of 1610. 4000 g of polyester was obtained. As a result of measuring the molecular weight of this polyester by GPC, the molecular weight in terms of polystyrene was a weight average molecular weight of 1610, and the hydroxyl value was measured to be 117.1 mgKOH / g.
To 4000 g of this unsaturated polyester, 0.50 g of hydroquinone was added and dissolved in 1000 g of styrene to prepare an unsaturated polyester resin (PE-8) having a viscosity (25 ° C.) of 28.0 dPa · s.

(Synthesis Example 9)
In the same one-step reaction method as in Synthesis Example 1, 1825 g of dicyclopentadiene and 250 g of water were charged, and 1321 g of maleic anhydride was added in 4 portions from 60 ° C. while being heated and stirred under a nitrogen stream while paying attention to the exothermic reaction. Then, the reaction was continued for 2 hours at 130 ° C. to synthesize dicyclopentadiene maleate and dicyclopentadiene fumarate. Subsequently, 77 g of benzyl alcohol and 70 g of maleic anhydride were added, and 1 hour while paying attention to heat generation at 100 ° C. Further, 302 g of propylene glycol and 457 g of dipropylene glycol were added, the temperature was gradually raised from 100 ° C., and esterification was conducted at 205 ° C. according to a standard procedure, and the mixture was cooled when the acid value reached 55.7 mgKOH / g. 4000 g of unsaturated polyester was obtained. As a result of measuring the molecular weight of this polyester by GPC, the molecular weight in terms of polystyrene was 930 in terms of weight average molecular weight, and as a result of measuring the hydroxyl value, it was 23.8 mgKOH / g.
Next, 0.50 g of hydroquinone was added to 4000 g of this unsaturated polyester and dissolved in 1000 g of styrene to prepare an unsaturated polyester resin (PE-9) having a viscosity (25 ° C.) of 8.5 dPa · s.

<Synthesis of (meth) acrylate oligomer>
(Synthesis Example 10)
A 2 liter flask equipped with a stirrer, condenser, thermometer and dry air inlet tube was charged with 2754 g of bisphenol A epoxy resin {AER 2603: Asahi Kasei Epoxy Co., Ltd., epoxy equivalent 186.2}, and a dry air atmosphere The mixture was heated while stirring at 90 ° C., and a solution of 1.2 g of methylhydroquinone dissolved in 404 g of methacrylic acid was added, and the catalyst 2,4,6-tris (dimethylaminomethyl) phenol (sequol) was further added at 110 ° C. TDMP) 10 g dissolved in 869 g of methacrylic acid was first reacted at 110 ° C., and then esterified at 130 ° C. according to a standard procedure, and cooled when the acid value reached 9.5 mg KOH / g. 4000 g of vinyl ester having a molecular weight of 860 was obtained. Hydroquinone 0.50 g was added and dissolved in 1000 g of styrene to prepare a vinyl ester resin (VE-1) having a viscosity (25 ° C.) of 13.1 dPa · s.

(Synthesis Example 11)
In the same manner as in Synthesis Example 11, 1000 g of styrene, 0.8 g of methylhydroquinone, and 1828 g of 4,4′-diphenylmethane diisocyanate were charged, the temperature was increased while stirring in a dry air atmosphere, and 2-hydroxypropyl methacrylate was obtained at 60 ° C. Charge 2211 g in portions while paying attention to heat generation, add 3.0 g of dibutyltin dilaurate as a catalyst at 70 ° C., gradually raise the temperature from 65 ° C., and conduct urethanation reaction at 75 ° C. according to a standard procedure. Then, the infrared absorption spectrum was measured to confirm that the absorption peak of the isocyanate group at 2100 to 2200 cm ⁻¹ disappeared, and then the reaction was stopped by cooling. A urethane methacrylate resin (UMA-1) having a solid weight average molecular weight of 760 and a viscosity (25 ° C.) of 19.2 dPa · s was obtained.

<Comparative synthesis example of vinyl ester resin>
(Synthesis Example 12)
In the same manner as in Synthesis Example 8, 2338 g of a bisphenol A epoxy resin {AER 2603: Asahi Kasei Epoxy Co., Ltd., epoxy equivalent 186.2}, 473 g of bisphenol A, and 0.9 g of triethylamine were added and stirred in a dry air atmosphere. The temperature was raised, the reaction was carried out at 135 ° C. to 145 ° C. for 1 hour, followed by charging at 90 ° C. with 1.2 g of methylhydroquinone dissolved in 241 g of methacrylic acid, and at 110 ° C., the catalyst 2,4,6-Tris ( A solution of 10 g of dimethylaminomethyl) phenol (sequol TDMP) dissolved in 482 g of methacrylic acid is gradually heated from 110 ° C. and subjected to an esterification reaction at 130 ° C. according to a standard procedure, resulting in an acid value of 11.8 mgKOH / g. When cooled, 3500 g of vinyl ester having a weight average molecular weight of 2050 was obtained. It was. 0.50 g of hydroquinone was added and dissolved in 1500 g of styrene to prepare a vinyl ester resin (VE-2) having a viscosity (25 ° C.) of 20.1 dPa · s.

(Synthesis Example 13)
In the same manner as in Synthesis Example 8, 2068 g of a cycloaliphatic epoxy resin [Celoxide 3000: manufactured by Daicel Chemical Industries, Ltd., epoxy equivalent 90.2] was charged, and the temperature was raised while stirring in a dry air atmosphere, and 90 ° C. A solution prepared by dissolving 1.2 g of methylhydroquinone in 657 g of methacrylic acid and further dissolving 10 g of catalyst 2,4,6-tris (dimethylaminomethyl) phenol (sequol TDMP) in 1314 g of methacrylic acid at 110 ° C. The temperature was gradually raised from 110 ° C. and an esterification reaction was carried out at 130 ° C. according to a standard procedure. When the acid value reached 15.3 mg KOH / g, the mixture was cooled to obtain 4000 g of vinyl ester having a weight average molecular weight of 480. It was. Hydroquinone 0.50 g was added and dissolved in 1000 g of styrene to prepare a vinyl ester resin (VE-3) having a viscosity (25 ° C.) of 10.2 dPa · s.

<Synthesis result>
Table 1 shows the results of synthesizing the resins of each synthesis example and comparative synthesis example and the liquid properties of the obtained curable resin composition. Each characteristic value was measured by the following method.
(1) Acid value and viscosity The acid value and viscosity of the unsaturated polyester, vinyl ester resin and urethane methacrylate resin obtained by synthesis were measured according to the method of JIS K 6901.
(2) Weight average molecular weight The polystyrene equivalent weight average molecular weight was measured by gel permeation chromatography (GPC) of the synthesized resin.

(Examples 1-7, Comparative Examples 1-13)
<< Evaluation of resin for lamination >>
In the compounding ratio of the resins shown in Table 2 (Examples 1 to 7), Table 3 (Comparative Examples 1 to 7), and Table 4 (Comparative Examples 8 to 13), Synthesis Examples 1 to 10 and Comparative Synthesis Examples 1 to 4 Resin modification and evaluation were carried out by combining the unsaturated polyester resin and the methacrylate resin by the following method. The criteria for the above workability evaluation and cured product characteristic evaluation are shown in Table 5.

<Adjustment of laminating resin>
500 parts by weight of the resin obtained by further mixing 500 parts by weight of the resin obtained by synthesis and 10 parts by weight of the silica-based thixotropic agent (Nippon Aerology Co., Ltd .: Aerology 200). , 4.0 parts by weight of a 6% cobalt naphthenate solution, 0.50 parts by weight of dimethylaniline, and 0.15 parts by weight of tertiary butylcatechol are added, and styrene is added as necessary. The viscosity is 250 to 400 dPa · The resin for laminating s was prepared. The viscosity, thixotropy index, and room temperature curability (25 ° C.) of these resins (gelation time, minimum curing time, maximum exothermic temperature, addition of 1.0 wt% of 55 wt% methyl ethyl ketone peroxide solution) is the method of JIS K 6901 Measured according to

<Evaluation of FRP lamination workability>
(1) Styrene odor As an evaluation of workability at the time of FRP laminating work, 180 parts by weight of unsaturated polyester resin for laminating resin was mixed with 1.8 parts by weight of 55% by weight methyl ethyl ketone peroxide solution, and mixed uniformly. A resin is impregnated into a 450 g / m ² glass fiber mat (manufactured by Nitto Boseki Co., Ltd .: MC450-N) cut to a size of 30 cm × 30 cm, and two glass mats are stacked and laminated in a 23 ° C. atmosphere. Cured. The amount of styrene volatilization at the time of this lamination operation (23 ° C., no wind) was measured with a Kitagawa type detector tube. Measurement was performed 30 cm above the laminated surface.

(2) Solubility of glass fiber mat As an evaluation of workability at the time of FRP laminating work, solubility of the secondary binder of the glass fiber mat in the resin was measured. A 450 g / m ² glass fiber mat (manufactured by Central Glass Co., Ltd .: ECM450-198Y-CT-N / C) is cut into a strip of 3 cm × 20 cm, and the center of the glass fiber mat is placed on a horizontal table. , Clamp a 200g weight on one end, and fix the other end to the base. Put a load (weight) on the glass fiber mat. Set a non-contact displacement meter that measures the displacement (movement) of the weight. Displacement measurement is started, and 15 parts by weight of the liquid resin for lamination is sprayed uniformly and quickly on the center of the glass fiber mat, and at the same time the start switch of the displacement meter is pressed. The time from spraying the resin onto the glass fiber mat until the resin penetrates the mat and the mat is cut was measured at 23 ° C. Measurement was performed 5 times. The cut time was read from the displacement meter data. The faster the solubility of the glass fiber mat (the time that the mat can be cut) is, the faster the glass fiber mat is unwound during molding, the faster the familiarity with the mat mold, and the better the workability.

(3) Evaluation of temperature dependence of viscosity with resin that does not impart thixotropy The resin that does not contain only the silica-based thixotropy imparting agent (Nippon Aerology Co., Ltd .: Aerology 200) is prepared by adjusting the resin for lamination. did. The viscosity of this resin at 5 ° C. and 25 ° C. was measured. The viscosity of only the resin not added with the silica-based thixotropy imparting agent has a correlation with sprayability and the like, and the lower the viscosity, the lower the viscosity at a low temperature of 5 ° C., and the lower the temperature dependency. Throughout the year, including winter, operations such as resin spray and spray-up can be performed well.

<Preparation of test piece for evaluating physical properties of cured product>
A mold in which 500 parts by weight of an unsaturated polyester resin for lamination is mixed with 5.0 parts by weight of a 55% by weight methyl ethyl ketone peroxide solution and uniformly mixed to obtain a plate-like cured product having a thickness of 4 mm. The mixture was allowed to stand at 25 ° C. for 16 hours to be cured, and post-cured at 120 ° C. for 2 hours. A test piece was produced from this cured product by cutting according to JIS standards.

<Physical properties of cured product>
(1) Boiling resistance, heat distortion temperature About the said test piece, the continuous boiling test of 100 degreeC was performed according to the method of JISK6911, and the generation | occurrence | production time of the blister (swelling / crack) was measured. Furthermore, the heat distortion temperature was measured in accordance with JIS K 6911 method.
(2) Tensile strength, tensile elastic modulus, tensile elongation rate The test piece was subjected to a tensile test according to JIS K 7162 method, and the tensile strength, tensile elastic modulus, and tensile fracture elongation were measured.
(3) Volume shrinkage The specific gravity of the liquid resin for laminating resin and its cured product was measured according to the JIS method, and the volume shrinkage was measured from the numerical value. When the volume shrinkage is smaller, a product excellent in the appearance with less warp and deformation of the FRP molded product and further with a glass fiber pattern is obtained.

Since the curable resin composition of the present invention has a low viscosity and can reduce the content of radical polymerizable monomer (for example, styrene) blended in the curable resin composition, not only can the radical polymerizable monomer volatility be reduced. The curable resin composition has excellent FRP (fiber reinforced plastic) molding (lamination) workability, and also provides a cured molded article having excellent mechanical properties and hot water resistance. The surface smoothness can be improved. Accordingly, the curable resin composition of the present invention is used as a base material for FRP (fiber reinforced plastic) used in, for example, construction materials, transportation equipment, industrial equipment, etc., or for castings, paints, adhesives, resin concrete, decorative boards. It can be used widely and advantageously.

Claims (15)

(A) Unsaturated polyester having a weight average molecular weight in terms of polystyrene of 1000 to 3000 having an alkyl alcohol residue and a dicyclopentadiene residue having one or more phenyl groups at the molecular end, (B) ) A curable resin composition comprising a (meth) acrylate oligomer having an acryloyl group and a weight average molecular weight in terms of polystyrene of 500 to 2000 and (C) a radical polymerizable monomer. The unsaturated polyester of component (A) is represented by the general formula (1)
R ¹ OCOCH = CHCO [OR ² OCOR ³ CO] _n OR ² OCOCH
= CHCOOR ¹ (1)
(Where R ¹ is Φ—R ⁴ —, dicyclopentadienyl group, H or —R ² OH, R ² is a polyhydric alcohol residue, and R ³ is an α, β-unsaturated polycarboxylic acid. A saturated polyvalent carboxylic acid or an aromatic polyvalent carboxylic acid residue, R ⁴ represents an alkylene group having 1 to 4 carbon atoms, Φ represents a phenyl group, and n is 0 or a positive number.)
Indicated by
The curable resin composition according to claim 1, wherein the (meth) acrylate oligomer of component (B) is a vinyl ester and / or urethane (meth) acrylate. In the unsaturated polyester of component (A), the total amount of phenyl alcohol groups and dicyclopentadiene residues is 70 mol or more with respect to 100 mol of terminal groups, and each of the phenyl alcohol groups is 3 mol or more, and dicyclopentadiene residues The curable resin composition according to claim 1 or 2, which is an unsaturated polyester containing 50 mol or more. The (A) component unsaturated polyester is (i) an alkyl alcohol having at least one phenyl group, (b) an alcohol component comprising a polyhydric alcohol, and (c) dicyclopentadiene maleate and / or dicyclopentadiene fuma. The curable resin composition according to claim 1, wherein the curable resin composition is an unsaturated polyester obtained by an esterification reaction using an acid component comprising a rate. The curable resin composition according to any one of claims 1 to 4, wherein the component (B) used as the component (A) is an alkylene glycol or dialkylene glycol having 3 to 6 carbon atoms having a side chain. The curable resin composition according to claim 4, which is an unsaturated polyester resin obtained as described above. Unsaturation obtained by using an alcohol component in which (B) component used in component (A) is a C 3-6 alkylene glycol or dialkylene glycol having a side chain, consisting of propylene glycol or dipropylene glycol The curable resin composition according to claim 4, which is a polyester resin. (B) component (meth) acrylate oligomer is represented by the general formula (2)
[CH ₂ = CR ⁵ COO] _m R ⁶ (2)
(Wherein R ⁵ represents hydrogen or a methyl group, R ⁶ represents a residue of an aromatic or aliphatic epoxy compound or epoxy resin, or a compound represented by the general formula (3)
^{-R 7 OCO [NHR 8 NHCOOR 9} OCO] j NHR 8 NHCOOR 7 -
.... (3)
R ⁷ represents an alkylene group having 2 to 5 carbon atoms, R ⁸ represents an alkylene group, an aromatic or aliphatic hydrocarbon residue, R ⁹ represents a polyhydric alcohol residue, m Represents an integer of 2 or more, and j represents an integer of 0 to 5. )
The curable resin composition of Claim 1 or 2 shown by these. The blending ratio of the unsaturated polyester (A) and the (meth) acrylate oligomer (B) is (A) / (B) = 30/70 to 95/5 (weight ratio). The curable resin composition according to any one of the above. The blending amount of the radically polymerizable monomer of the component (C) is 20 to 100 parts by weight with respect to a total of 100 parts by weight of the unsaturated polyester of the component (A) and the (meth) acrylate oligomer of the component (B). The curable resin composition according to 1. (B) esterification using an alkyl alcohol having at least one phenyl group, (b) an alcohol component comprising a polyhydric alcohol, and (c) an acid component comprising dicyclopentadiene fumarate or dicyclopentadiene fumarate Unsaturated polyester having a weight average molecular weight in terms of polystyrene of 1000 to 3000 having an alkyl alcohol residue having at least one phenyl group and a dicyclopentadiene residue at the molecular end obtained by reaction, (B) molecule A method for producing a curable resin composition comprising, at the end, a (meth) acrylate oligomer having a (meth) acryloyl group and a weight average molecular weight in terms of polystyrene of 500 to 2000 and (C) a radically polymerizable monomer. . The radical curable resin composition which mix | blended the radical polymerization initiator with the curable resin composition of any one of Claims 1-9. A resin composite composition obtained by combining the curable resin composition according to claim 11 and a fiber reinforcing material and / or filler / aggregate. A laminated cured product obtained by molding and curing the radically curable resin composition or the resin composite composition according to claim 11 or 12. An FRP composite material obtained by curing the radically curable resin composition or the resin composite composition according to claim 11. A method for producing a molded body, comprising molding and curing the radically curable resin composition or the resin composite composition according to claim 11 or 12.