JPH04198209A - Dicyclopentadiene-modified unsaturated polyester composition and its use - Google Patents

Abstract

PURPOSE:To form a cured fiber-reinforced laminate of excellent surface smoothness by using a composition prepared by mixing a specified dicyclopentadiene- modified unsaturated polyester with a low-molecular-weight dicyclopentadiene- modified unsaturated polyester. CONSTITUTION:The title composition comprises (A) a dicyclopentadiene-modified unsaturated polyester of formula I (wherein R1 is a residue derived by removing the hydroxyl groups from a dihydric alcohol; R2 is a residue derived by removing the carboxyl groups from an unsaturated or saturated dibasic acid; and n is an integer of 1-100) obtained by reacting dicyclopentadiene maleate and/or fumarate with a mixture of a dihydric alcohol component containing at least 2wt.% dihydric alcohols having a bisphenol skeleton and/or a hydrogenated bisphenol skeleton with an unsaturated dibasic acid, a saturated dibasic acid or an acid anhydride thereof and (B) a low-molecular-weight dicyclopentadiene- modified unsaturated polyester of formula II (wherein R3 is a residue of a dihydric alcohol) obtained by reacting dicyclopentadiene maleate and/or fumarate with a dihydric alcohol.

Description

Detailed Description of the Invention [Field of Industrial Application] The present invention relates to a dicyclopentadiene-modified unsaturated polyester composition and its use, and the dicyclopentadiene-modified unsaturated polyester composition is free from radical In combination with a polymerizable monomer, it is possible to obtain a fiber-reinforced laminate cured product, especially a fiber-reinforced laminate cured product that has less fiber patterns, sink marks, and warpage on the gel coat surface of the fiber-reinforced cured laminate and has excellent surface smoothness. suitable for

[Conventional technology]

In general, unsaturated polyester resins or vinyl ester resins (hereinafter, to avoid confusion, types to which radically polymerizable monomers are added are referred to as unsaturated polyester resins or vinyl ester resins, and types to which radically polymerizable monomers are not added are referred to as unsaturated polyester resins). Fiber composite materials using resins (also known as vinyl esters) are easily released from the mold surface due to curing shrinkage of the resin, resulting in fiber patterns, sink marks, warpage, etc. occurring on the surface of the cured product, resulting in poor product quality. Reduces surface smoothness of appearance. As a method to improve this drawback, a dicyclopentadiene-modified unsaturated polyester resin is obtained by reacting dicyclopentadiene maleate and/or dicyclopentadiene fumarate with an aliphatic dihydric alcohol such as ethylene glycol or diethylene glycol. Although the method of using is widely used, it cannot be said that the effect of improving surface smoothness is sufficient.

Sheet molding compounds (SMC) or bulk molding compounds (BMC), which are thickened and heat-molded, are made with thermoplastic polymers (e.g., polystyrene, polyvinyl acetate) as low-shrinkage materials. Products with excellent smoothness can be obtained, but in laminated cured products made by hand lay-up molding or spray-up molding, SMC or BMC
As the viscosity cannot be increased, the compatibility between unsaturated polyester resin or vinyl ester resin and thermoplastic polymer is poor, and therefore, even if a thermoplastic polymer is added, the thermoplastic polymer separates in a relatively short period of time. , products with excellent surface smoothness cannot be obtained, and secondary processing (polishing and polishing) takes time. Even if a thermoplastic polymer that is relatively compatible with unsaturated polyester resin or vinyl ester resin (e.g. polyvinyl acetate) is added and cured at room temperature by hand lay-up molding or spray-up molding, the resin will not harden. Heat generation alone does not provide a sufficient shrinkage reduction effect.

Therefore, a product with excellent surface smoothness cannot be obtained, and secondary processing takes time.

[Problem to be solved by the invention]

The present invention is a diode suitable for improving the surface smoothness of fiber-reinforced laminate cured products formed from fiber composite materials using unsaturated polyester resins or vinyl ester resins, which has been disadvantageous in conventional methods. A cyclopentadiene-modified unsaturated polyester composition, a curable dicyclopentadiene-modified unsaturated polyester resin composition obtained by blending this dicyclopentadiene-modified unsaturated polyester composition with a radically polymerizable monomer, and a curable dicyclopentadiene-modified unsaturated polyester resin composition using this composition. The purpose of the present invention is to provide a fiber-reinforced laminate cured product molded by the above method and a method for producing the same.

[Means to solve the problem]

As a result of intensive studies to solve the drawbacks of the prior art, the present inventors discovered that the present inventors have a dicyclopentadiemaleate group or a dicyclopentadiene fumarate group at the end of the molecule, and a bisphenol skeleton and/or a bisphenol skeleton in the intramolecular skeleton. A dicyclopentadiene-modified unsaturated polyester having a hydrogenated bisphenol skeleton (A'l) and a low molecular weight dicyclopentadiene-modified unsaturated polyester having a dicyclopentadiene maleate group or a dicyclopentadiene fumarate group at the molecular end [ It has been discovered that a composition containing B) effectively achieves the above object, and that a fiber-reinforced laminate cured product has excellent surface smoothness, leading to the present invention.

That is, the present invention provides at least 20 wt. General formula (1) obtained by reacting a mixture of a dihydric alcohol containing an unsaturated dibasic acid, a saturated dibasic acid, or an acid anhydride thereof [However, in the formula, R1 is divalent a/L, coal represents a residue obtained by removing a hydroxyl group from , R2 represents a residue obtained by removing a carboxyl group from an unsaturated dibasic acid or a saturated dibasic acid, and n is 1 to
Represents an integer of +00. ] dicyclopentadiene-modified unsaturated polyester [A]; (B) (a) dicyclopentadiene malate and/or
Or, the formula (2) obtained by reacting dicyclopentadiene fumarate and (b) dihydric alcohol [However, R3 represents a residue obtained by removing the hydroxyl group from the dihydric alcohol. ] It relates to a dicyclopentadiene-modified unsaturated polyester composition which is blended with a low molecular weight dicyclopentadiene-modified unsaturated polyester CB) represented by:

The present invention also relates to a curable dicyclopentadiene-modified unsaturated polyester resin composition, which is obtained by blending a radically polymerizable monomer into the dicyclopentadiene-modified unsaturated polyester composition.

Furthermore, the present invention relates to a fiber-reinforced laminate cured product comprising a cured product of a fiber-reinforced material containing the above-mentioned curable dicyclopentadiene-modified unsaturated polyester resin composition.

Furthermore, the present invention impregnates a fiber reinforcing material with the curable dicyclopentadiene-modified unsaturated polyester resin composition and cures it to produce a fiber-reinforced laminate cured product. 69] 1934-1
) relates to a method for producing a fiber-reinforced laminate cured product, characterized in that demolding is performed after confirming that the hardness value of the cured product is 80% or more of the fully cured hardness value of the cured product. .

Hereinafter, preferred embodiments will be explained to help understand the present invention.

First, the dicyclopentadiene-modified unsaturated polyester (A) represented by the general formula (1) of the present invention can be produced, for example, by the following method.

Maleic anhydride and water are reacted at 60 to 100°C to produce maleic acid, and maleic acid and dicyclopentadiene are then reacted at 120 to 140°C to produce dicyclopentadiene malate and/or dicyclopentadiene fumarate. After synthesizing the compound, a dihydric alcohol containing at least 20% by weight of a dihydric alcohol having a bisphenol skeleton and/or a hydrogenated bisphenol skeleton, i.e., a bisphenol skeleton and/or a hydrogenated bisphenol in a total amount of 100% by weight of the dihydric alcohol. A dihydric alcohol containing 20 to 100% by weight of a dihydric alcohol having a skeleton is subjected to an esterification reaction with an unsaturated dibasic acid, a saturated dibasic acid, or an acid anhydride thereof.

Below, dicyclopentadiene, maleic anhydride, water, and dihydric alcohol having a bisphenol skeleton are 2,2
A typical reaction formula for synthesizing dicyclopentadiene-modified unsaturated polyester [A] using -di(4-hydroxypropoxyphenyl)propane and phthalic anhydride is shown.

Dicyclopentadiene maleate and/or dicyclopentadiene fumarate, which are raw materials for producing the cyclopentadiene-modified polyester [A') used in the present invention, are as shown in formulas (1) and (2) above. Alternatively, the synthesis may be carried out by reacting maleic anhydride and water to produce maleic acid, and then reacting this maleic acid with dicyclopentadiene, or by directly reacting maleic acid and dicyclopentadiene. It may also be synthesized by Furthermore, it is also possible to synthesize dicyclopentadiene alcohol in combination with maleic anhydride, maleic acid, fumaric acid, or the like.

Examples of dihydric alcohols having a bisphenol skeleton or hydrogenated bisphenol skeleton include 2,2-di(4-hydroxypropoxyphenyl)propane and 2,2-di(4-di(4-hydroxypropoxyphenyl)propane).
Most commercially available dihydric alcohols such as -hydroxycyclohexyl)propane, di(4-hydroxypropoxyphenyl)methane, and di(4-hydroxycyclohexyl)propane can be used.

These dihydric alcohols may be used in combination.

Other two used in combination with dihydric alcohol having a bisphenol skeleton and/or hydrogenated bisphenol skeleton
Polyester resins such as ethylene glycol, propylene glycol, diethylene glycol, dipropylene glycol, neopentyl glycol, 1,3-butanediol, 1,4-butanediol, I,6-hexanediol, etc. Commercially available compounds used in can be used.

When a mixture of a dihydric alcohol having a bisphenol skeleton and/or a hydrogenated bisphenol skeleton and another dihydric alcohol is used as the dihydric alcohol, the content of the dihydric alcohol having a bisphenol skeleton and/or a hydrogenated bisphenol skeleton If it is less than 20% by weight based on 100% by weight of the mixture, even if the obtained dicyclopentadiene-modified unsaturated polyester resin is used to produce a fiber-reinforced laminate cured product, the fiber-reinforced laminate cured product with excellent surface smoothness will not be produced. I can't get it.

Unsaturated dibasic acids or their anhydrides include maleic anhydride, maleic acid, fumaric acid, itaconic anhydride, itaconic acid, citraconic acid, etc., all of which are commonly used in the synthesis of unsaturated polyesters. can.

Saturated dibasic acids or their acid anhydrides include phthalic anhydride, isophthalic acid, terephthalic acid, tetrahydrophthalic anhydride, methyltetrahydrophthalic anhydride, endomethylenetetrahydrophthalic anhydride, adipic acid, sebacic acid, het acid, and tetrabromide. Examples include phthalic anhydride.

Next, the low molecular weight dicyclopentadiene-modified unsaturated polyester CB) represented by the above-mentioned amount (2) of the present invention can be produced, for example, by the following method.

Maleic anhydride and water are reacted at 60 to 100°C to produce maleic acid, and maleic acid and dicyclopentadiene are then reacted at 120 to 140°C to produce dicyclopentadiene maleate and/or dicyclopentadiene fumale.
After synthesizing 1., dihydric alcohol is subjected to an esterification reaction.

A typical reaction formula for synthesizing dicyclopentadiene-modified unsaturated polyester [B) using dicyclopentadiene, maleic anhydride, water, and propylene glycol is shown below.

"Low molecular weight" in the low molecular weight dicyclopentadiene-modified unsaturated polyester ['B] means that the unsaturated polyester [B] is a combination of dicyclopentadiene maleate and/or dicyclopentadiene fumarate and dihydric alcohol. Since it is a reaction product, it theoretically becomes a non-repeating form as shown in general formula (2), and unless a dihydric alcohol with a particularly large molecular weight is used, unsaturated dibasic acids, saturated dibasic acids, or their A large amount (11
Since it has a lower molecular weight than the dicyclopentadiene-modified unsaturated polyester (A) having repeats such as
Unsaturated polyester [A] and unsaturated polyester [B
] is used to distinguish between.

Dicyclopentadiene maleate and/or dicyclopentadiene fumarate, which are raw materials for producing the low molecular weight dicyclopentadiene-modified polyester CB used in the present invention, are expressed by the formula (+) and formula (2) above. As shown, maleic acid may be synthesized by reacting maleic anhydride and water, and then this maleic acid and dicyclopentadiene may be reacted, or maleic acid and dicyclopentadiene may be synthesized. It may be synthesized by direct reaction. Furthermore, dicyclopentadiene alcohol and maleic anhydride,
It is also possible to synthesize by combining maleic acid, fumaric acid, etc.

Examples of dihydric alcohols include ethylene glycol, propylene glycol, diethylene glycol, dipropylene glycol, neopentyl glycol, 1.3-butanediol, 1.4-butanediol, 1.6-hexanediol, bisphenol skeleton or hydrogenated bisphenol. 2,2-di(
4-hydroxypropoxyphenyl)propane, 2,2
-di(4-hydroxycyclohexyl)propane, di(
4-hydroxypropoxyphenyl)methane, di(4-
Most commercially available dihydric alcohols such as hydroxycyclohexyl)propane can be used.

The dicyclopentadiene-modified unsaturated polyester composition of the present invention comprises a dicyclopentadiene-modified unsaturated polyester (A) and a low molecular weight dicyclopentadiene-modified unsaturated polyester [B] in a weight ratio of CA]/CBI (weight ratio )=90-20/10-80, preferably 70-30/
It can be adjusted by blending at a ratio of 30 to 70.

When the blending ratio of the unsaturated polyester CA) exceeds 90, workability tends to be poor unless a large amount of radically polymerizable monomer is blended, and as a result, the surface smoothness of the cured product tends to deteriorate. This tendency becomes particularly noticeable when the molecular weight of the unsaturated polyester [A) becomes large. On the other hand, if the blending ratio of the unsaturated polyester [A] is less than 20, the effect of improving surface smoothness is not sufficient.

This dicyclopentadiene-modified unsaturated polyester composition has a high viscosity and is insufficiently cured as it is, so it is usually used with a radically polymerizable monomer added thereto.

The curable dicyclopentadiene-modified unsaturated polyester resin composition of the present invention can be easily prepared by blending a radically polymerizable monomer with the dicyclopentadiene-modified unsaturated polyester composition.

In addition, dicyclopentadiene-modified unsaturated polyester (
A) and low molecular weight dicyclopentadiene-modified unsaturated polyester CB) are each blended with a radically polymerizable monomer to create a curable resin composition, and then these curable resin compositions are blended and cured. A dicyclopentadiene-modified unsaturated polyester resin composition may be prepared.

The radically polymerizable monomer used in the present invention includes:
Known and publicly used styrene, vinyl toluene, used in ordinary unsaturated polyester resins or vinyl ester resins,
Vinyl compounds such as α-methylstyrene, chlorostyrene, vinylnaphthalene, ethyl vinyl ether, methyl vinyl ketone, methyl acrylate, ethyl acrylate, methyl methacrylate, acrylonitrile, methacrylonitrile, and diallyl phthalate, diallyl fumarate, diallyl succinate, triallyl Vinyl monomers or vinyl oligomers that can be crosslinked with the dicyclopentadiene-modified unsaturated polyester composition, such as allyl compounds such as isocyanurate, can be used alone or in combination, but styrene is generally used.

The blending ratio of the dicyclopentadiene-modified unsaturated polyester composition and the radically polymerizable monomer is dicyclopentadiene-modified unsaturated polyester composition/radically polymerizable monomer (weight ratio) = 90-30/10-70, preferably 70-50/30-50.

When the blending ratio of the dicyclopentadiene-modified unsaturated polyester composition exceeds 90, molding workability is poor. Moreover, when the blending ratio of the dicyclopentadiene-modified unsaturated polyester composition is less than 30, the surface smoothness of the cured product decreases.

A polymerization inhibitor is usually added to the curable dicyclopentadiene-modified unsaturated polyester resin composition. Examples of the polymerization inhibitor used include known and publicly used polymerization inhibitors used in common unsaturated polyester resins or vinyl ester resins, such as hydroquinone, p-benzoquinone, methylhydroquinone, and catechol.

The curable dicyclopentadiene-modified unsaturated polyester resin composition of the present invention can be easily cured by adding a curing catalyst and a curing accelerator that are used for curing ordinary unsaturated polyester resins or vinyl ester resins. be able to.

Examples of the curing catalyst used include organic peroxides such as methyl ethyl ketone peroxide, t-butyl peroxybenzoate, benzoyl peroxide, dicumyl peroxide, and cumene hydroperoxide. The amount of curing catalyst used is preferably 0.5 to 3 parts by weight per 100 parts by weight of the dicyclopentadiene-modified unsaturated polyester resin composition.

Examples of the curing accelerator include cobalt naphthenate, cobalt octoate, dimethylaniline, diethylaniline, and acetylacetone.

The amount of curing accelerator used is [1
,01 to 3 parts by weight are preferred.

The curable dicyclopentadiene-modified unsaturated polyester resin composition of the present invention can be used to easily obtain a fiber-reinforced laminate cured product using fiber reinforcement in the same manner as ordinary unsaturated polyester resins or vinyl ester resins. can.

As fiber reinforcing agents, glass fiber, polyester fiber,
Chopped strand mats, rovings, etc. of fibers such as acrylic fibers, vinylon fibers, carbon fibers, polyamide fibers, steel fibers, silk fibers, wool fibers, cotton fibers, etc.
Any commercially available fibers such as roving cloth, woven, knitted, thread-like, and non-woven fabrics can be used.

Examples of methods for producing the fiber-reinforced laminate cured product of the present invention include open methods such as hand lay-up method, spray-up method, and filament winding method, and closed methods such as resin injection molding method and resin transfer molding method.

In the method for manufacturing a fiber-reinforced laminated cured product, the hardness value of the cured product in Barcol hardness measurement (JIS K 6911934-1) is 8% of the fully cured hardness value of the cured product.
It is necessary to perform demolding after reaching 0% or more, preferably 90% or more. If demolding is performed at less than 80%,
After demolding, curing progresses (curing shrinkage progresses) and fiber patterns tend to occur on the gel coat surface, resulting in poor surface smoothness.

Thus, a fiber-reinforced laminate cured product obtained from a curable dicyclopentadiene-modified polyester resin composition having a bisphenol skeleton and/or a hydrogenated bisphenol skeleton and a fiber reinforcing material exhibits excellent surface smoothness.

〔Example〕

EXAMPLES Next, examples will be shown to explain the present invention in more detail, but the scope of the present invention is not limited by these examples. In addition, unless otherwise specified, parts in Examples and Comparative Examples are parts by weight.

Synthesis of dicyclopentadiene-modified unsaturated polyester (A) Synthesis example 1 Dicyclopentadiene 760 was placed in a four-bottle flask equipped with a thermometer, stirring blade, inert gas introduction tube, and condenser.
2.2.
-1930 g of di(4-hydroxypropoxyphenyl)propane was charged and a dehydration condensation reaction was carried out in a conventional manner. The reaction was stopped when the acid value reached 18 ■KOH/g, and dicyclopentadiene-modified unsaturated polyester [A] was obtained. 0.5g of hydroquinone was added to this unsaturated polyester [A], and 1490g of styrene monomer was added.
The viscosity at 25°C is 40 poise and the acid value is 12.5.
(2) A resin composition (A)-(]) of KOH/g was obtained.

In addition, unsaturated polyester [A
) has a number average molecular weight of 1140 and a weight average molecular weight of 202.
It was 0.

Synthesis Example 2 In the same manner as Synthesis Example 1, 825 g of dicyclopentadiene
110 g of water and 560 g of maleic anhydride were charged and reacted, and then 420 g of phthalic anhydride and 2070 g of 2,2-di(4-hydroxypropoxyphenyl)propane were charged and reacted. The reaction was stopped when the acid value reached 15 ■KOH/g, and a dicyclopentadiene-modified unsaturated polyester (A) was obtained (number average molecular weight was 850,
Weight average molecular weight is 27110). Add 0.5 g of hydroquinone to this unsaturated polyester (A) and dissolve it in 1250 g of styrene monomer to obtain a resin composition with a viscosity of 40 poise at 25°C and an acid value of 13 KOH/g [A) -(
2) was obtained.

Synthesis Example 3 In the same manner as Synthesis Example 1, 310 g of dicyclopentadiene
85 g of water and 550 g of maleic anhydride were charged and reacted.

Next, 2,230 g of 2,2-di(4-hydroxycyclohexyl)propane and 560 g of phthalic anhydride were charged.
Dehydration condensation was carried out using a conventional method. Acid value is 19■KO
The reaction was stopped when H/g was reached, and a dicyclopentadiene-modified unsaturated polyester [A] was obtained (number average molecular weight: 920, weight average molecular weight: 3560). 0.5 g of hydroquinone was added to this unsaturated polyester [A] and dissolved in 2000 g of styrene monomer to obtain a resin composition [A)-(3) having a viscosity of 45 poise at 25°C.

Synthesis Example 4 In the same manner as Synthesis Example 1, 355 g of dicyclopentadiene
Then, 425 g of 2,2-di(4-hydroxypropoxyphenyl)propane I, 730 g of diethylene glycol, and 635 g of phthalic anhydride were charged and reacted. The reaction was stopped when the acid value reached 15 KOII/g, and a dicyclopentadiene-modified unsaturated polyester (A) was obtained (number average molecular weight: 1080, weight average molecular weight: 3900). 0.5 g of hydroquinone was added to this unsaturated polyester [A], and 15 g of styrene monomer (
1 (dissolved in l g, viscosity at 25°C is 21 poise,
Resin composition [A]-(4
) was obtained.

Synthesis Example 5 In the same manner as in Synthesis Example 1, dicyclopentadiene 2000
g, 270 g of water, and 1355 g of maleic anhydride were charged and reacted, and then 565 g of propylene glycol was charged and reacted. The reaction was stopped when the acid value reached 15 ■KOH/g, and a low molecular weight dicyclopentadiene-modified unsaturated polyester CB) was obtained. Hydroquinone 05g1 Styrene 1250
g was added and dissolved to obtain a resin composition [B]-(5) having an acid value of 11.2 ■KOH/g and a viscosity of 5.5 poise.

In addition, unsaturated polyester [B] measured by GPC
] has a number average molecular weight of 350 and a weight average molecular weight of I'10.
It was 0.

Synthesis Example 6 In the same manner as Synthesis Example 1, dicyclopentadiene 2020
After that, 270 g of water and 1325 g of maleic anhydride were charged and reacted, and then 480 g of ethylene glycol was charged and reacted. The reaction was stopped when the acid value reached 16.5 ■KOH/g, and a low molecular weight dicyclopentadiene-modified unsaturated polyester [B] was obtained (number average molecular weight: 340, weight average molecular weight: 96Q).

Hydroquinone 0.5 to this unsaturated polyester CB)
g, 1250 g of styrene was added and dissolved, and the acid value was 11.6.
■KOH/g 1 viscosity 4.5 poise resin composition [B
] -(6) was obtained.

Synthesis Example 7 In the same manner as in Synthesis Example 1, dicyclopentadiene 1890
g, 260 g of water, and 1275 g of maleic anhydride were charged and reacted, and then 760 g of diethylene glycol was charged and reacted. The reaction was stopped when the acid value reached 17.5 mmKOtl/g, and a low molecular weight dicyclopentadiene-modified unsaturated polyester [B] was obtained (number average molecular weight: 400, weight average molecular weight: 1080). Add and dissolve 0.5 g of nohydroquinone and 1250 g of styrene into this unsaturated polyester CB) to obtain an acid value of 13.1 KO.
H/g, viscosity 34 poise resin composition CB]-(7
) was obtained.

Example 1 Resin composition (Al-(1) 200 parts Resin composition (B3) 200 parts Styrene 95 parts 6% Cobalt naphthenate 2.5 parts and 55% methyl ethyl ketone peroxide 50 parts A curable dicyclopentadiene-modified unsaturated polyester resin composition was obtained.

Using this curable resin composition, apply gel coat resin to a thickness of about 0.3 mm on a glass plate that has been subjected to mold release treatment in advance, cure it and leave it at room temperature for 16 hours, then apply it on the cured gel coat resin surface. , 450 of size 35×35CIIr
g/n(glass chopped strand mat and 570
Using glass roving cloth of g/rrf, five layers were laminated in the order of mat, mat, roving cloth, mat, and roving cloth impregnated with a curable resin composition and cured. One day after the resin composition gelled, the Barcol hardness of the laminate (Its K 69+1934-1
) is 80% or more of the final hardness, then remove the mold, wait one day after removing the mold, cut a part of the laminate and heat it at 50°C.
I put it in the oven for 3 hours. The image clarity measuring machine (Suga Test Machine (Kikki ICM-IDP
) was evaluated. A laminate was made in the same manner, and 5 hours after the resin composition gelled, it was confirmed that the hardness was less than 80% of the final hardness, and the mold was demolded, and the surface condition was evaluated in the same manner.

Example 2 Resin composition (A: l-(2) 200 parts resin composition CB)-(6) 20 (1 part styrene 60 parts 6% cobalt naphthenate 2.5 parts), 55% methyl ethyl ketone par 4.5 parts of oxide was added and mixed, a laminate was produced in the same manner as in Example 1, and the surface condition was evaluated.

Example 3 Resin composition [A: l - (3) 2 parts resin composition CB) - (6) 2 [10 parts Styrene 70 parts 6% Cobalt naphthenate 2.5 parts were blended, 55% methyl ethyl ketone 45 parts of peroxide was added and mixed, a laminate was produced in the same manner as in Example 1, and the surface condition was evaluated.

Example 4 Resin composition [A)-(4) 200 parts Resin composition (B)-(7) 2 parts styrene
75 parts 2.5 parts of 6% cobalt naphthenate were blended, 4.5 parts of 55% methyl ethyl ketone peroxide was added and mixed, and Example 1
A laminate was prepared in the same manner as above, and the surface condition was evaluated.

Example 5 Resin composition (A) - (2) 200 parts Resin composition [B] - (7) 200 parts Styrene 70 parts 6% Cobalt naphthenate 2.5 parts were blended, 55% methyl ethyl ketone peroxide 45 A laminate was prepared in the same manner as in Example 1, and the surface condition was evaluated.

Comparative Example 1 959 g of dicyclopentadiene was prepared in the same manner as in Synthesis Example 1.
Then, 129 g of ethylene glycol, 770 g of diethylene glycol, and 774 g of phthalic anhydride were charged, and dehydration condensation was carried out using a conventional reaction method. acid value is 1
7■KO) I/'g to stop the reaction and hydroquinone 0.
5 g was added and dissolved in 1750 g of styrene monomer to obtain a resin composition having a viscosity of 5 poise at 25°C. 6% cobalt naphthenate to 400 parts of this resin composition 2.
0 parts and 4.4 parts of 55% methyl ethyl ketone peroxide were blended to obtain a curable resin composition. Hereinafter, a laminate was prepared in the same manner as in Example 1, and the surface condition was evaluated.

Comparative Example 2 Using a normal unsaturated polyester resin reactor, 85g of propylene glycol and 1110g of phthalic anhydride
and 735 g of maleic anhydride were charged and a dehydration condensation reaction was carried out in a conventional manner. Acid value: 30■KOII/g
Stop the reaction when the temperature reaches 100 ml, cool, add 0.3 g of hydroquinone and 12 Hg of styrene monomer, and dissolve.
A resin composition having an acid value of 21 ■KOH/g and a viscosity at 25°C of 16 poise was obtained. A curable resin composition was obtained by blending 40 parts of styrene monomer, 2.0 parts of 6% cobalt naphthenate, and 44 parts of 55% methyl ethyl ketone peroxide to 400 parts of this resin composition. Hereinafter, a laminate was produced in the same manner as in Example 1, and the surface condition was evaluated.

Example 6 Resin composition [A) - (2) 135 parts Resin composition [:B] - (7) 265 parts Styrene 55 parts 6% Cobalt naphthenate 2.2 parts were blended, and 55% methyl ethyl ketone peroxide 4.5 parts were added and mixed, a laminate was produced in the same manner as in Example 1, and the surface condition was evaluated.

Table 1 shows the results of the evaluation of the surface conditions of the laminates produced in Examples 1 to 6 and Comparative Examples 1 to 2.

In Table 1, the visual evaluation of the laminate is as follows: ◎Excellent smoothness, ○Excellent smoothness, △fair, and ×poor. The numbers in parentheses represent the smoothness of the laminate placed in an oven at 50°C for 3 hours. The closer the image clarity value is to 100%, the closer it is to a mirror surface, and the closer it is to 0%, the worse the surface condition is. The measurement of image clarity was 0.5 mm < I at an incident angle of 60 degrees.
I did it in a shape pattern.

〔Effect of the invention〕

According to the present invention, a dicyclopentadiene modified immobilizer having a dicyclopentadiene maleate group and/or a dicyclopentadiene fumarate group at the molecular terminal and a bisphenol skeleton and/or a hydrogenated bisphenol skeleton in the internal skeleton. A dicyclopentadiene-modified unsaturated polyester can be produced by blending a saturated polyester with a low molecular weight dicyclopentadiene-modified unsaturated polyester having a dicyclopentadiene maleate group and/or a dicyclopentadiene fumarate group at the molecular end. The composition can be easily obtained by changing the types and combinations of raw ingredients.
A wide variety of dicyclopentadiene-modified unsaturated polyester compositions can be prepared. In addition, when a resin composition formed by blending a radically polymerizable monomer with this dicyclopentadiene-modified unsaturated polyester composition is used in the production of a fiber-reinforced laminate cured product, the surface condition of the fiber-reinforced laminate cured product is significantly affected. It provides a fiber-reinforced laminated cured product with improved surface smoothness.

Patent applicant: Showa Kobunshi Co., Ltd.

Claims (4)

[Claims] (1) (A) A dihydric alcohol containing at least 20% by weight of (a) dicyclopentadiene malate and/or dicyclopentadiene fumarate and (b) a dihydric alcohol having a bisphenol skeleton and/or a hydrogenated bisphenol skeleton. obtained by reacting a mixture of with an unsaturated dibasic acid, a saturated dibasic acid, or an acid anhydride thereof,
General formula (1) ▲There are mathematical formulas, chemical formulas, tables, etc.▼ (1) [However, in the formula, R_1 represents a residue obtained by removing the hydroxyl group from a dihydric alcohol, and R_2 is an unsaturated dibasic acid or a saturated dibasic acid. Represents the residue obtained by removing the carboxyl group from , where n is 1 to
Represents an integer of 100. ] Dicyclopentadiene-modified unsaturated polyester [A] and [B] obtained by reacting (a) dicyclopentadiene malate and/or dicyclopentadiene fumarate, and (b) dihydric alcohol , General formula (2) ▲Mathematical formulas, chemical formulas, tables, etc.▼(2) [However, R_3 represents the residue obtained by removing the hydroxyl group from the dihydric alcohol. ] A dicyclopentadiene-modified unsaturated polyester composition comprising a low molecular weight dicyclopentadiene-modified unsaturated polyester [B] represented by: (2) A curable dicyclopentadiene-modified unsaturated polyester resin composition obtained by blending the dicyclopentadiene-modified unsaturated polyester composition according to claim (1) with a radically polymerizable monomer. (3) A fiber-reinforced laminate cured product comprising a cured fiber-reinforced material containing the curable dicyclopentadiene-modified unsaturated polyester resin composition according to claim (2). (4) When producing a fiber-reinforced laminate cured product by impregnating and curing the curable dicyclopentadiene-modified unsaturated polyester resin composition according to claim (2),
Fiber reinforcement characterized by demolding after confirming that the hardness value of the cured product is 80% or more of the fully cured hardness value of the cured product in Barcol hardness measurement (JISK6911934-1) A method for manufacturing a laminated cured product.