JPH01115954A - Unsaturated polyester resin composition - Google Patents

Abstract

PURPOSE:To obtain a resin composition having excellent compound viscosity characteristics before curing and giving a cured article having excellent surface characteristics and impact resistance, by compounding an unsaturated polyester resin with a specific modified hydrogenated block copolymer, a vinyl monomer and a hardener. CONSTITUTION:The objective composition is composed of (A) 10-90pts.wt. of an unsaturated polyester resin, (B) 2-70pts.wt. of a modified hydrogenated block copolymer produced by hydrogenating >=80% of aliphatic double bond originated from conjugated diene of a block copolymer composed of an aromatic vinyl compound and a conjugated diene compound and grafting 100pts.wt. of the resultant hydrogenated product with 0.01-20pts.wt. of an epoxy group- containing unsaturated compound (e.g., glycidyl methacrylate), (C) 10-80pts.wt. of a vinyl monomer and (D) 0.1-10pts.wt. (based on 100pts.wt. of the sum of A-C) of a hardener (e.g., organic peroxide). The composition can be produced by separately preparing the 1st mixture containing the components A and C and the 2nd mixture containing the components B and C, adding the component D and other additive to at least one of the mixtures and mixing the mixtures with each other.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention provides excellent performance in compound viscosity characteristics before curing, surface characteristics (surface smoothness, surface gloss) of molded products after curing, and impact resistance. The present invention relates to an unsaturated polyester resin composition which can be used as a sheet molding compound (SMG) or a bulk molding compound (BMC).

[Conventional technology]

In recent years, as the movement to reduce the weight of automobiles has become more active,
Attempts have been made to use unsaturated polyester resins in the exterior and structural parts of automobiles.

Generally, molded products using unsaturated polyester resin are
Since the molding shrinkage rate during curing is as high as 4 to 12%, thermoplastic resins such as polystyrene, polymethyl methacrylate, and polyvinyl acetate are usually blended as "low shrinkage agents."

However, even in these cases, phase separation may occur between the unsaturated polyester resin and the low-shrinkage agent after compounding, and undesirable surface characteristics such as warpage and waviness may still be induced in the molded product. I'm staying with the current situation. Therefore, in unsaturated polyester resin compositions, not only improvement of impact resistance but also surface properties and thickening properties after compounding tend to be emphasized, and improvement thereof has become an important issue.

For this reason, many attempts to improve these improvements have been proposed. For example, in JP-A-48-34289 and JP-A-49-30480, unsaturated styrene-butadiene block copolymers are added. Polyester resin compositions have been proposed. However, in these methods, the added styrene-butadiene block copolymer component and unsaturated polyester resin component undergo phase separation after compounding, resulting in a cured product with poor surface properties and impact resistance. is the current situation.

In an attempt to improve this drawback, Japanese Patent Application Laid-Open No. 52-1485
88 and JP-A-54-130653 propose unsaturated polyester resin compositions containing a styrene-butadiene block copolymer containing a carboxyl group or a salt thereof at the end of the molecular chain. However, even with these methods, the problem of phase separation between the rubber component and the unsaturated polyester resin component cannot be essentially solved, and the actual situation is that the surface properties and impact resistance have not been improved.

Under these circumstances, attempts to further improve these problems were made in Japanese Patent Laid-Open Nos. 56-115309 and 1987-1.
15310, the content of which is an unsaturated polyester resin characterized in that a modified block copolymer in which dicarboxylic acid Ml and/or its derivative group is bonded to a styrene-butadiene block copolymer is added. It is necessary for the composition. Also, for the same purpose, JP-A-58-
No. 8718 discloses a modified hydrogenated block copolymer in which a molecular unit containing a carboxylic acid group or a derivative group thereof is bonded to a hydrogenated block copolymer obtained by hydrogenating a styrene-butadiene block copolymer. A method of adding . However, although the use of these modified block copolymers has improved the problem of phase separation after compounding with the base unsaturated polyester component, the surface properties of the resulting cured product are still insufficient.
Furthermore, from a manufacturing standpoint, the handling viscosity is too high and the thickening properties are insufficient.

[Means for solving problems]

The present invention was made to solve the problems that could not be solved with the conventional techniques described above, and by using a specific modified hydrogenated block copolymer, it is possible to improve not only impact resistance but also surface smoothness and surface smoothness. This invention was made based on the discovery that a cured product of an unsaturated polyester resin composition having excellent gloss and dimensional stability can be obtained.

That is, the present invention comprises (a) an unsaturated polyester resin, (b) a polymer block A mainly composed of at least one vinyl aromatic compound, and a polymer block B mainly composed of at least one conjugated diene compound. To 100 parts by weight of a hydrogenated block copolymer obtained by hydrogenating a block copolymer consisting of and hydrogenating at least 80% of the aliphatic double bonds based on the conjugated diene compound in the copolymer,
Provided is an unsaturated polyester resin composition comprising a modified hydrogenated block copolymer grafted with 0.01 to 20 parts by weight of an epoxy group-containing unsaturated compound, (C) a vinyl monobase, and (d) a curing agent. It is something.

The present invention will be described in detail below.

In the present invention, the unsaturated polyester resin used as component (a) is obtained by a synthetic reaction of an α,β-unsaturated dibasic acid or a mixture of this and a saturated dibasic acid, and a polyhydric alcohol. Examples of the dibasic acid component include maleic acid, fumaric acid, itaconic acid, citraconic acid,
Mention may be made of mesaconic acid, chlorinated maleic acid, glutaconic acid or acid anhydrides thereof. In addition, examples of saturated dibasic acids include phthalic acid, halogenated phthalate, isophthalic acid, terephthalic acid, tetrahydrophthalic acid, hydrophthalic acid, endomethylenetetrahydrophthalic acid, succinic acid, adipic acid, glutaric acid, cepatic acid, pimelic acid, or These acid anhydrides can be mentioned. Furthermore, if necessary, a monobasic acid such as acrylic acid or methacrylic acid or a polybasic acid such as trimellitic acid, hemimellitic acid or trimesic acid can be used in combination with the above-mentioned two-base UQ as a modifying agent.

Polyhydric alcohols include ethylene glycol, diethylene glycol, triethylene glycol, polyethylene glycol, propylene glycol, dipropylene glycol, tripropylene glycol, polypropylene glycol, 1,3-butanediol, tetramethylene glycol, 1,6-hexanediol, neo Examples include pentyl glycol, 1,4-cyclohexane dimetatool, and ethylene oxide and/or propylene oxide adducts of hydrogenated bisphenol A. Further, if necessary, higher aliphatic alcohols such as amyl alcohol, hexyl alcohol, pentyl alcohol, and octyl alcohol, and polyhydric alcohols such as tetrahydrofurfuryl alcohol can be used in combination.

The method for producing the unsaturated polyester resin obtained from these components may be any known method.

Next, the modified hydrogenated block copolymer used as component (b) of the present invention is a hydrogenated block copolymer to which an epoxy group-containing unsaturated compound is grafted, and the hydrogenated block copolymer serving as the base thereof is obtained by hydrogenating a block copolymer consisting of a polymer block A mainly composed of at least one vinyl aromatic compound and a polymer block B mainly composed of at least one conjugated diene compound. For example, A-B, A-B-A, B-A-8
-A, (A B )4 Si, A B A-
It is a hydrogenated vinyl aromatic compound-conjugated diene compound block copolymer having a structure such as B-A. This hydrogenated block copolymer contains a vinyl aromatic compound in an amount of 5 to 95% by weight, preferably 10 to 80% by weight. is a homopolymer block of a vinyl aromatic compound or a copolymer block of a vinyl aromatic compound and a hydrogenated conjugated diene compound containing more than 50% by weight and preferably 70% by weight or more of a vinyl aromatic compound. structure, and furthermore, the polymer block mainly composed of a hydrogenated conjugated diene compound is a homopolymer block of a hydrogenated conjugated diene compound, or a polymer block mainly composed of a hydrogenated conjugated diene compound. %, preferably 70% by weight or more, of a copolymer block of a hydrogenated conjugated diene compound and a vinyl aromatic compound. In addition, the polymer block A mainly composed of these vinyl aromatic compounds and the polymer block B mainly composed of a hydrogenated conjugated diene compound are hydrogenated conjugated diene compounds in the molecular chains of each polymer block. Alternatively, the distribution of the vinyl aromatic compound may be random, highly birded (increasing or decreasing the heptamer component along the molecular chain), partially block-like, or any combination thereof, and the vinyl aromatic compound When there are two or more polymer blocks mainly composed of a compound and two or more polymer blocks mainly composed of the hydrogenated conjugated diene compound, each polymer block may have the same structure, or may have a different structure. It may be.

As the vinyl aromatic compound constituting the hydrogenated block copolymer, one or more types can be selected from, for example, styrene, α-methylstyrene, vinyltoluene, p-tert-butylstyrene, etc. Among them, styrene is preferable.

Further, examples of the conjugated diene compound before hydrogenation constituting the hydrogenated conjugated diene compound include butadiene, isoprene, 1,3-pentadiene, 2,3-dimethyl-
One or more types are selected from 1,3-butadiene and the like, and among them, butadiene, isoprene, and a combination thereof are preferred. The microstructure of a polymer block mainly composed of a conjugated diene compound before hydrogenation can be arbitrarily selected; for example, in a polybutadiene block, a 1,2-vinyl bond structure or a 20-vinyl bond structure is used. ~65%, preferably 25-45%.

Further, the number average molecular weight of the hydrogenated block copolymer used in the present invention having the above structure is 5,000 to i, ooo
, ooo, preferably 10,000 to aoo, oo
o, more preferably in the range of 30,000 to 500,000, and the molecule population distribution [ratio of weight average molecule i (Hw) to number average molecular weight (Hw) (Hw/)In)] is 10 or less . The molecular structure of Zarani hydrogenated block copolymer is
It may be linear, branched, radial, or any combination thereof.

These block copolymers may be produced by any method as long as they have the above-mentioned structure. For example, special public relations
According to the method described in Japanese Patent No. 23798, a vinyl aromatic compound (9) was prepared in an inert solvent using a lithium catalyst.
As a method for synthesizing a di-ene compound block copolymer and then producing a hydrogenated product of the vinyl aromatic compound-conjugated diene compound block copolymer, for example,
2-8704 and the method described in Japanese Patent Publication No. 43-6636 (9), the hydrogenated block copolymer produced by JQ exhibits excellent weather resistance and heat deterioration resistance. Hydrogenated block copolymers synthesized using titanium-based hydrogenation catalysts are most preferred; for example, JP-A-59
The modified hydrogenated block copolymer of the present invention is produced by hydrogenation in the presence of a titanium-based hydrogenation catalyst in an inert solvent by the method described in JP-A-133203 and JP-A-60-79005@. A hydrogenated block copolymer serving as a base can be synthesized. At that time, at least 80% of the aliphatic double bonds based on the conjugated diene compound of the vinyl aromatic compound-conjugated diene compound block copolymer are hydrogenated, and the polymer block mainly composed of the conjugated diene compound is transformed into an olefin. It is necessary to avoid converting the compound into a polymer block.

In addition, hydrogen of an aromatic double bond based on a vinyl aromatic compound copolymerized into a polymer block A mainly composed of a vinyl aromatic compound and, if necessary, a polymer block B mainly composed of a conjugated diene compound. Although there is no particular restriction on the addition rate, it is preferable that the hydrogenation rate is 20% or less. The amount of non-hydrogenated aliphatic double bonds contained in the hydrogenated block copolymer can be easily determined using an infrared spectrophotometer, nuclear magnetic resonance apparatus, or the like.

Next, as the epoxy group-containing unsaturated compound used in the synthesis of the modified hydrogenated block copolymer of the present invention, all compounds having an unsaturated group and an epoxy group in the molecule can be used, but preferred epoxy group-containing compounds can be used. Examples of the unsaturated compounds include compounds represented by the following general formulas (I> and (II)).

(In the formula, R represents hydrogen, a lower alkyl group, or a lower alkyl group substituted with a glycidyl ester group.) (In the formula, R represents hydrogen, a lower alkyl group, or a lower alkyl group substituted with a glycidyl ester group. ) Preferred specific examples include glycidyl acrylate, glycidyl methacrylate, glycidyl ethacrylate, glycidyl itaconate, allyl glycidyl ether, etc. Among them, preferred epoxy group-containing unsaturated compounds include glycidyl acrylate and glycidyl methacrylate. ,
Allyl glycidyl ether is mentioned.

In addition to these epoxy group-containing unsaturated compounds, maleic acid diglycidyl ester, maleic acid methylglycidyl ester, maleic acid ethylglycidyl ester, maleic acid isopropylglycidyl ester, maleic acid t
-butyl glycidyl ester, fumaric acid diglycidyl ester, fumaric acid methyl glycidyl ester, fumaric acid isopropyl glycidyl ester, itaconic acid diglycidyl ester, itaconic acid methyl glycidyl ester,
Epoxy group-containing unsaturated compounds such as isopropylglycidyl itaconate, diglycidyl 2-methyleneglutarate, and methylglycidyl 2-methyleneglutarate can also be suitably used.

These epoxy group-containing unsaturated compounds may be one or two types.
More than one species can be used.

In order to obtain the modified hydrogenated block copolymer of the present invention, the amount of the epoxy group-containing unsaturated compound used during graft modification is usually 0.02 to 100 parts by weight per 100 parts by weight of the hydrogenated block copolymer.
It can be suitably used in a range of 30 parts by weight.

The modified hydrogenated block copolymer of the present invention is obtained by grafting the above-mentioned epoxy group-containing unsaturated compound onto the hydrogenated block copolymer having the above structure in the presence or absence of an organic peroxide. The reaction can be carried out in either a molten state or a solution state.

In addition, the modified hydrogenated block copolymer obtained by this modification reaction is 0.0% per 100 parts of the hydrogenated block copolymer.
1 to 20 parts by weight, preferably 0.05 to 10 parts by weight, more preferably 0.1 to 5 parts by weight of the epoxy group-containing unsaturated compound is grafted, and the unreacted epoxy group-containing unsaturated compound is It may contain up to 29.99 parts by weight. Grafting amounts other than this will not give favorable results regarding the thickening properties and phase separation of the resulting unsaturated polyester resin composition after compounding, and in particular, if the grafting amount exceeds 20 parts by weight, the desired This gives a compound with a much higher viscosity than the viscosity at the time of molding, making it difficult to mold, which is undesirable.

Therefore, grafting amounts outside these ranges are not preferable because the resulting cured product will have non-uniformity in surface characteristics and physical properties.

Next, examples of organic peroxides that can be provided as needed in the graft reaction of this modified hydrogenated block copolymer include dicumyl peroxide and diter
tert-butyl peroxide, tert-butylcumyl peroxide, 2,5-dimethyl-2,5-di(tert)
t-butylperoxy)hexane, 2,5-dimethyl-
2,5-di(tert-butylperoxyhexine-3)
, n-butyl-4,4-bis(tert-butylperoxy)valerate, 1,1-bis(tert-butylperoxy)3.3.5-trimethylcyclohexane, and the like. You can choose one or more types.

In addition to these organic peroxides, radical initiators such as 2,3-dimethyl-2,3,diphenylbutane, 2,
3-diethyl-2,3-diphenylbutane, 2,3-dimethyl-2,3-di(p-methylphenyl)butane, 2
, 3-dimethyl-2°3-di(bromophenyl)butane or the like may be used for the graft reaction.

The above-mentioned organic peroxides and radical initiators that can be used in this graft reaction can be preferably used in an amount of usually 0.01 to 5 parts by weight per 100 parts by weight of the hydrogenated block copolymer.

Furthermore, unreacted epoxy group-containing unsaturated compounds may be completely removed from the modified hydrogenated block copolymer of the present invention, or
Alternatively, it may be left as is. The production method can be carried out by any known method. For example, when the modified hydrogenated block copolymer is obtained using a mixer such as an extruder, the modified hydrogenated block copolymer is produced using a vent extruder. While carrying out the reaction, the amount of unreacted epoxy group-containing unsaturated compounds remaining in the hydrogenated block copolymer may be controlled by forced venting. Furthermore, for example, an epoxy group-containing unsaturated compound can be grafted to the hydrogenated block copolymer in a state in which it is dissolved in a solvent or in a state in which it is in suspension.

When carrying out these graft reactions, it is also possible to coexist a vinyl monobase that is copolymerizable with the epoxy group-containing unsaturated compound, and naturally the modified hydrogenated block copolymer obtained here can be used as the base of the present invention. It can be suitably used as component (b).

As the copolymerizable vinyl monomer, for example, vinyl monomers such as styrene, acrylonitrile, acrylic ester, and methacrylic ester can be suitably used.

In addition, the amount of the grafted epoxy group-containing unsaturated compound in the modified hydrogenated block copolymer can be easily determined by a known method, specifically, using an infrared spectrophotometer, NM
It can be determined by instrumental analysis such as R, titration analysis of epoxy value, etc. Further, the remaining amount of the unreacted epoxy group-containing unsaturated compound contained in the modified hydrogenated block copolymer of the present invention can be easily measured by, for example, gas chromatography.

As mentioned above, the method for producing the modified hydrogenated block copolymer of the present invention is not particularly limited in the present invention. Production methods that include undesirable components or that significantly increase the melt viscosity and solution viscosity and deteriorate processability are not preferred. As an example of a preferable manufacturing method, for example, 1 in a vented extruder
Melt the above-mentioned hydrogenated block copolymer, epoxy group-containing unsaturated compound, vinyl monomer copolymerizable with the epoxy group-containing unsaturated compound, organic peroxide, etc. at a temperature of 50 to 350 ° C. There is a method of kneading and radical modification. At this time, a stabilizer may be added as necessary to prevent the formation of gel or the like. This stabilizer is
Known antioxidants include phenolic antioxidants, phosphorus antioxidants, and sulfur antioxidants, which can be used alone or in combination.

Next, the vinyl monomer used as component (C) in the present invention is a compound (unsaturated polyester resin composition).
acts as a crosslinking component. Examples of vinyl monomers include styrene, various substituted forms of styrene, such as α
-Methylstyrene, vinyltoluene, dimethylstyrene, trimethylstyrene, halogenated styrene, tert
- Vinyl aromatic compounds such as butylstyrene, styrene sulfonate, aminostyrene, p-benzylstyrene, p-phenoxystyrene, acrylic acid or methacrylic acid and methyl alcohol, ethyl alcohol, propyl alcohol, octyl alcohol, hexanol, tetrahydrofuryl Esters with aliphatic alcohols such as furyl alcohol, ethylene glycol, propylene glycol, etc., acrylic or methacrylic acid derivatives such as 2-aminoethyl-methacrylate, N,N-diethylamino-acrylate, N,N-diethylamino-methacrylate, maleic acids, α, β-unsaturated dicarboxylic acids such as fumaric acid, crotonic acid, itaconic acid, etc., or their acid anhydrides, esters, amides, imides, etc., fumaric acid esters such as diethyl fumarate, dioctyl fumarate, etc. , various vinyl monomers and vinylidene monomers, such as acrylonitrile, methacrylaterile,
Vinyl acetate, vinyl chloride, vinylidene chloride, vinylene carbonate, vinyl-2-chloroethyl ether, C8
-C18 alkyl vinyl ether, 08-C18 fatty acid vinyl ester, 2-vinylfuran, vinylphenol, vinylphenyldisiloxane, 2-vinylpyridine, 4-vinylpyridine, vinylvirol, vinylpyrrolidone, vinylsulfonic acid, vinylurethane , methylvinylketone-2-vinylquinoline, vinylcarbazole, and the like. Also used are conjugated diene compounds such as 1,3-butadiene, isoprene, piperylene, methylpentadiene, chloroprene, and alkoxy and cyano derivatives of conjugated dienes such as 2-methoxybutadiene and 1-cyanobutadiene. I can do it. Furthermore, polyfunctional crosslinkable vinyl monomer 1 such as diallyl maleate, diallyl phthalate, divinylbenzene, divinyl ether, neopentyl glycol diacrylate, diallyl cyanurate, triallyl cyanurate, diallylphenyl phosphate, 2.3
-Divinylpyridine, divinylsulfone, 2,5-divinyl-6-methylpyridine, etc. can also be used. Preferred examples of these vinyl monomers include styrene, vinyltoluene, α-methylstyrene, chlorostyrene, divinylbenzene, methyl methacrylate, methyl acrylate, diallyl phthalate, and triallyl cyanurate.

As the curing agent as the component (d>) used in the present invention, organic peroxides, organic hydroperoxides, and azo compounds can be used.

Some peroxides useful in this invention include dialkyl peroxides and diacyl peroxides. Alkyl peroxides have the general structure R-00-R-, where R and R' are the same or different first-
1 secondary or tertiary alkyl group, cycloalkyl group,
It is an aralkyl group or a heterocyclic group. Groups of peroxides suitable for use in the compositions of the invention include dicumyl peroxide, di-tert-butyl peroxide,
tert-butylcumyl peroxide and 2゜5-
Also included is dimethyl-2,5-bis(tert-butylperoxy)hexane.

Diacyl peroxide has the general structure RC(0)-00-
C(0)R″′, where R and R′ are the same or different alkyl, cycloalkyl, aralkyl, aryl or heterocyclic groups. Some suitable for use in the present invention Examples of diacyl peroxides include dilauroyl peroxide, dibenzoyl peroxide, diacyl peroxide, dibenzoyl peroxide, di(2,4-dichlorobenzoyl) peroxide, diisononanoyl peroxide and 2-methylpentanoyl. There is peroxide.Furthermore,
Other peroxides useful in the present invention include methyl ethyl ketone peroxide, cyclohexanone peroxide, and the like, along with particularly preferred peresters such as tert-butyl peroxide and tert-butyl perbenzoate.

Examples of hydroperoxides suitable for use in the present invention include, for example, tert-butyl hydroperoxide, cumyl hydroperoxide, 2,5-dimethyl-2,5-cybidroba-oxyhexane, p-
Mentha hydroperoxide and diisopropylbenzene hydroperoxide. Examples of azo compounds that can be used in the present invention include diazoaminobenzene, N,N-dichloroazodicarboxylic acid amide,
Azodicarboxylic acid diethyl ester, 1-cyano-1-
(tert-butylazo)cyclohexanone and azobis(isobutyronitrile).

The blending ratio of each component constituting the unsaturated polyester resin composition of the present invention is (a> component 10 to 90 parts by weight, preferably 20 to 80 parts by weight, more preferably 20 to 60 parts by weight, (b) ) component in 2 to 70 parts by weight, preferably 5 to 5 parts by weight.
It is composed of 0 parts by weight, more preferably 5 to 409 parts by weight, and 10 to 80 parts by weight, preferably 20 to 70 parts by weight of component (C), and the (d>component of the curing agent is )
~0.1 to 10 per 100 parts by weight of component (C)
Parts by weight, preferably 0.3 to 5 parts by weight, more preferably 0.5 to 3 parts by weight.

In addition, desired amounts of various organometallic compounds and the like can be added as curing accelerators, if necessary.

In addition to the above, it is also a practical aspect of the present invention that the composition of the present invention may contain the above-mentioned unmodified hydrogenated block copolymer and the above-mentioned block copolymer before hydrogenation in any ratio. Other additives such as thickeners, fiber reinforcing materials, inorganic fillers, low shrinkage agents, pigments, colorants, lubricants, mold release agents, etc. may be added as necessary. I can do it.

The above-mentioned thickener is 0.5 to 10 parts by weight, preferably 1 part by weight, per 100 parts by weight of the components (a) to (C) of the composition of the present invention.
-5 parts by weight can be suitably selected and used.

In addition, fiber reinforcement materials include glass, metal, silicate, asbestos,
It is selected from fibers such as cellulose, carbon, graphite, polyester, polyacrylic, polyamide, and polyolefin, and preferably glass fiber.

These fiber reinforcing materials may be used in an amount of 0 to 300 parts by weight, preferably 5 to 200 parts by weight, and more preferably 20 to 100 parts by weight per 100 parts by weight of components (a) to (C) of the composition of the present invention. It can be suitably used within the range.

Inorganic fillers that can be used in the composition of the present invention are inorganic particulate fillers, such as calcium carbonate, calcium silicate, silica, calcined clay, chalk, talc, limestone, anhydrous calcium sulfate, barium acid, It can be selected from asbestos, powdered glass, quartz, aluminum hydrate, aluminum oxide, antimony oxide, etc., provided that it is added in an amount of 50 to 800 parts per 100 parts by weight of components (a) to (C) of the composition of the present invention. It can be used in an amount of 100 to 400 parts by weight, more preferably 100 to 300 parts by weight. In addition, low shrinkage agents that can be used in the composition of the present invention include polystyrene, poly(meth),
T) Any homopolymer or copolymer can be selected from acrylate-based, polyvinyl acetate-based, polyvinyl chloride-based, polyethylene-based, polypropylene-based, polyamide-based, polycarbonate-based, and cellulose-based polymers, and the amount added is Composition (a) of the present invention
It can be used in an amount of 0 to 40 parts by weight, preferably 2 to 20 parts by weight, per 100 parts by weight of component (C).

A preferred method for producing the unsaturated polyester resin composition of the present invention is as follows.

That is, a first mixture containing an unsaturated polyester resin which is the component (a) of the present invention and a vinyl monomer which is the component (C), a modified hydrogenated block copolymer which is the component (b), and (
A second mixture containing a vinyl monomer as component C) is mixed, and at this time, either one or both of the first mixture and the second mixture is filled with a curing agent as component (d) and, if necessary, This manufacturing method involves mixing additives such as a fiber reinforcing agent, a thickening agent, a low shrinkage agent, and a mold release agent.

The unsaturated polyester resin composition of the present invention obtained by these methods can be molded into a cured product by a method such as compression molding or injection molding, preferably through an intermediate compound such as SMC or BMC.

〔Effect of the invention〕

By using a specific modified hydrogenated block copolymer as the component (b), the present invention improves the initial viscosity of the compound, and reduces the decrease in viscosity during heating, and improves surface properties, dimensional stability, and impact resistance. It is possible to provide an unsaturated polyester resin composition with excellent properties.

The unsaturated polyester resin composition of the present invention is particularly useful for automobile parts including automobile outer panels, transportation equipment such as boats, bathtubs,
It can be suitably used as a structural material for septic tanks, vanity tables, chairs, etc.

〔Example〕

EXAMPLES The present invention will be described in detail with reference to examples, but the present invention is not limited thereto.

Reference Example 1: Preparation of unsaturated polyester resin 0.7 mol of maleic anhydride, 1.4 mol of phthalic anhydride, 2.0 mol of propylene glycol, 0.0 mol of diethylene glycol.
A mixture consisting of 2 moles was heated to about 100 °C under a nitrogen stream, stirred, and heated to about 21 °C while removing condensed water from the system.
The temperature was gradually raised to 0° C., and an esterification reaction was carried out at this temperature to synthesize an unsaturated polyester resin with an oxidation level of 40. This unsaturated polyester resin was dissolved in styrene, and a solution having a solid content concentration of 65% by weight was used as the component (a-1>).

Also, 110.6 mol of isophthalic acid, 0.6 mol of phthalic anhydride
A mixture consisting of 1.4 moles of maleic anhydride and 2.6 moles of propylene glycol was subjected to an esterification reaction in the same manner as above to synthesize an unsaturated polyester resin with an oxidation level of 30. This unsaturated polyester resin was dissolved in styrene, and a solution with a solid content concentration of 65% by weight was used as the (a-2> component).

<Reference Example 2>: Preparation of modified hydrogenated block copolymer having the structure of hydrogenated polybutadiene-polystyrene-hydrogenated polybutadiene-polystyrene,
Bonded styrene matrix 18% by weight, 1,2-vinyl bond loss in polybutadiene part before hydrogenation 43%, number average molecular weight 5
7,000, a molecular weight distribution of 1°03, and a hydrogenation rate of 99%, a hydrogenated block copolymer was synthesized using a Ti-based hydrogenation catalyst described in JP-A-59-133203.

5.0 parts by weight of glycidyl methacrylate and 0.6 parts by weight of di-tert-butyl peroxide were mixed per 100 parts by weight of this hydrogenated block copolymer, and a 45#φ vented twin shaft was heated at 190°C. The modification reaction was carried out in an extruder while performing forced venting (degree of vacuum near 50 mmHg gauge pressure) using a vacuum pump. The obtained modified hydrogenated block copolymer was refluxed for 20 hours using a Soxhlet extractor using acetone, and titration analysis of the epoxy value revealed that 2.9 parts by weight of glycidyl methacrylate had been grafted.

Further, unreacted glycidyl methacrylate contained in this modified hydrogenated block copolymer was 0.8 parts by weight.

This product was dissolved in styrene as component (C), and a solution with a solid content concentration of 30% by weight was used as component (b-1>).

Next, it has a structure of (polystyrene-hydrogenated polybutadiene-)4-3i, and 130% by weight of bound styrene.
, the amount of 1,2-vinyl bonds in the polybutadiene moiety before hydrogenation is 60%, and the number average molecular weight is 93,000. Molecular weight distribution 1
．． 48, a hydrogenated block copolymer with a hydrogenation rate of 99% was synthesized using a Ti-based hydrogenation catalyst described in JP-A-59-133203. Per 100 parts of this hydrogenated block copolymer, 1.0 parts by weight of glycidyl methacrylate,
0.5 parts by weight of rt-butyl peroxide was mixed and subjected to forced venting using a vacuum pump in a 45 Nnφ vented twin-screw extruder set at 190°C (degree of vacuum: 75
The denaturation reaction was carried out under a pressure of 0 mmHg (gauge pressure). The obtained modified hydrogenated block copolymer was refluxed for 20 hours using a Soxhlet extractor using acetone, and titration analysis of the epoxy value revealed that 0.6 parts by weight of glycidyl methacrylate was grafted. Further, this modified hydrogenated block copolymer contained 0.05 parts by weight of unreacted glycidyl methacrylate. This product was dissolved in styrene as component (C), and a solution with a solid content concentration of 30% by weight was used as component (b-2).

Furthermore, polystyrene-hydrogenated polybutadiene-
Has a polystyrene structure, 130% by weight of bound styrene
, the amount of 1,2-vinyl bonds in the polybutadiene moiety before hydrogenation is 32%, and the number average molecular weight is 44,000. Molecular weight distribution 1
．． 05, a hydrogenated block copolymer with a hydrogenation rate of 99% was synthesized using a Ti-based hydrogenation catalyst described in JP-A-59-133203. 2.0% glycidyl methacrylate per 100 parts by weight of this hydrogenated block copolymer. O-shaped mouth, G-te
45# mixed with 0.5 parts by weight of rt-butyl peroxide and set at 190°C! Forced venting (degree of vacuum:
The denaturation reaction was carried out under a pressure of 750 mmHg (gauge pressure). The obtained modified hydrogenated block copolymer was refluxed for 20 hours using a Soxhlet extractor using acetone, and titration analysis of the epoxy value revealed that 1.4 parts by weight of glycidyl methacrylate had been grafted. Moreover, the modified hydrogenated block copolymer after extraction with acetone did not contain any unreacted glycidyl methacrylate.

This modified hydrogenated block copolymer containing no unreacted glycidyl methacrylate was dissolved in styrene as component (C), and a solution with a solid content concentration of 30% by weight was used as component (b-3>).

Examples 1 to 4, Examples 1 to 3 Styrene solution of unsaturated polyester resin as component (a) synthesized in Reference Example, styrene solution of modified hydrogenated block copolymer as component (b), component (d) tert-butyl peroxybenzoate, zinc stearate, calcium carbonate and magnesium oxide were blended in the composition shown in Table 1,
A compound before curing was obtained.

This compound was aged in an oven at 40°C for 48 hours, and the viscosity of the aged compound at 23°C and the viscosity of this aged compound at 70°C were measured using a Brookfield viscometer (BT type).

The results are listed in Table 1.

In the comparative example, a styrene solution of the corresponding unreacted hydrogenated block copolymer was used instead of the styrene solution of the modified hydrogenated block copolymer as component (b).

These results revealed that the unsaturated polyester resin composition of the present invention had a higher compound viscosity at 70° C. than the comparative example, and was characterized by less decrease in viscosity upon heating.

Applications 5-8 Comparisons 4-6 Each of the basic formulations of Examples 1-4 and Comparative Examples 1-3 contained 10 glass fibers (PPG-3198; manufactured by PPG).
0 parts were blended to prepare SMC, and the mixture was aged at 40°C for 48 hours. Thereafter, it was pressure-molded at 140° C. under conditions of 85 to 9/- to obtain a cured unsaturated polyester resin composition.

Table 2 shows the results of measuring the physical properties of each molded product.

From this result, the unsaturated polyester resin composition of the present invention has no surface smoothness such as "large undulations" or "small undulations" and has a surface gloss of 60% or more, which is excellent. The surface properties were shown. Furthermore, the shrinkage rate during molding was negative (expansion), and it was found that it is highly effective as a low-shrinkage agent. On the other hand, it was revealed that the unsaturated polyester resin composition using the unmodified hydrogenated block copolymer shown in the comparative example was poor in the balance of surface smoothness, surface gloss, and low shrinkage.

(Margin below)

Claims (1)

[Claims] 1. (a) an unsaturated polyester resin; (b) a polymer block A mainly composed of at least one vinyl aromatic compound and a polymer mainly composed of at least one conjugated diene compound; 100 parts by weight of a hydrogenated block copolymer obtained by hydrogenating a block copolymer consisting of block B and hydrogenating at least 80% of the aliphatic double bonds based on the conjugated diene compound in the copolymer. To,
An unsaturated polyester resin composition comprising a modified hydrogenated block copolymer grafted with 0.01 to 20 parts by weight of an epoxy group-containing unsaturated compound, (c) a vinyl monomer, and (d) a curing agent.