JPH0333746B2 - - Google Patents

Description

[Detailed description of the invention]

(Industrial Application Field) The present invention is a sheet molding compound that exhibits excellent performance in compound viscosity characteristics before curing, surface characteristics (surface smoothness, surface gloss), and impact resistance of molded products after curing. (SMC) also relates to unsaturated polyester resin compositions which can also be used as bulk molding compounds (BMC). (Prior Art and its Problems) In recent years, as the movement toward weight reduction of automobiles has become more active, attempts have been made to use unsaturated polyester resins for outer panel parts and structural parts of automobiles. In general, molded products using unsaturated polyester resins have a mold shrinkage rate of 4 to 12% during curing, so thermoplastic resins such as polystyrene, polymethyl methacrylate, and polyvinyl acetate are usually used. It is formulated as a "low shrinkage agent". However, even in this case, phase separation may occur between the unsaturated polyester resin and the low-shrinkage agent after compounding, and warping or warping may occur even if the molded product is formed.
The current situation is that undesirable surface characteristics such as waviness are still being induced. Therefore, in unsaturated polyester resin compositions, in addition to improving impact resistance, there is a tendency to emphasize these surface properties and thickening properties after compounding, and improving them has become an important issue. There is. For this reason, many attempts to improve these properties have been proposed. For example, JP-A-48-34289 and JP-A-49-30480 propose a method of adding a styrene-butadiene block copolymer. has been done. 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. This is the actual situation. In an attempt to improve this drawback, JP-A-52-
No. 148588 and Japanese Unexamined Patent Publication No. 130653/1988 propose a method of adding 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 component cannot be essentially solved, and the reality is that the surface properties and impact resistance have not been improved. Under these circumstances, furthermore,
Attempts to improve this drawback have been proposed in JP-A-56-115309 and JP-A-56-115310. It is characterized by adding a modified block copolymer to which groups are bonded. Furthermore, for the same purpose, JP-A-58-8718 discloses that a molecular unit containing a carboxylic acid group or its derivative group is added to a hydrogenated block copolymer obtained by hydrogenating a styrene-butadiene block copolymer. A method has been proposed in which a modified block copolymer with which is bonded is added. However, although the above-mentioned problem of phase separation after compounding with the unsaturated polyester component has been improved by using these modified block copolymers, the surface properties of the cured products obtained are still insufficient, and further manufacturing From the above viewpoints, the handling viscosity was too high and the thickening properties were still insufficient. (Means for Solving the Problems) The present invention was made to solve the above-mentioned problems under the conventional technology, and by using specific components, surface smoothness, surface gloss, and size can be improved. It has been discovered that a cured composition of an unsaturated polyester resin composition with excellent stability can be obtained, and it has also been discovered that the composition is a practically useful composition. 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. Hydrogenating a block copolymer consisting of
A modified hydrogen block in which a molecular unit containing a carboxylic acid group or a derivative group thereof is bonded to a hydrogenated block copolymer in which at least 80% of the aliphatic double bonds based on a conjugated diene compound in the copolymer are hydrogenated. Copolymer (c) 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, in which a carboxylic acid group is added. The present invention provides an unsaturated polyester resin composition comprising: (d) a modified block copolymer bonded with molecular units containing or derivative groups thereof; (d) a vinyl monomer; (e) a curing agent. The present invention will be described in detail below. The unsaturated polyester resin used as component (a) in the present invention is obtained by a condensation reaction between an α,β-unsaturated dibasic acid or a mixture of this and a saturated dibasic acid and a polyhydric alcohol. be. Examples of this dibasic acid component include maleic acid, fumaric acid,
Mention may be made of itaconic acid, citraconic acid, mesaconic acid, chlorinated maleic acid, glutaconic acid or acid anhydrides thereof. In addition, saturated dibasic acids include phthalic acid, halogenated phthalic acid, isophthalic acid, terephthalic acid, tetrahydrophthalic acid, hettic acid, endomethylenetetrahydrophthalic acid,
Mention may be made of succinic acid, adipic acid, glutaric acid, sebacic acid, pimelic acid or acid anhydrides thereof. Also, if necessary, acrylic acid,
Monobasic acids such as methacrylic acid and polybasic acids such as trimellitic acid, hemimelittic acid and trimesic acid can also be used in combination with the dibasic acids mentioned above as modifiers. 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, neopentyl glycol, 1,4-cyclohexanedimethanol, hydrogenated bisphenol A, bisphenol A
Examples include ethylene oxide and/or propylene oxide adducts. Further, if necessary, higher aliphatic alcohols such as amyl alcohol, hexyl alcohol, pentyl alcohol, octyl alcohol, etc., monohydric alcohols such as tetrahydrofurfuryl alcohol, polyhydric alcohols such as glycerin, pentaerythritol, trimethylolethane, sorbitol, etc. It can also be used in combination with alcohol. Next, the modified hydrogenated block copolymer used as component (b) of the present invention comprises a polymer block A mainly composed of at least one vinyl aromatic compound,
A block copolymer consisting of a polymer block B mainly composed of at least one conjugated diene compound is hydrogenated, and at least 80% of the aliphatic double bonds based on the conjugated diene compound in the copolymer are hydrogenated. This is a modified block copolymer (hereinafter abbreviated as "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. Here, the hydrogenated block copolymer is, for example,
A-B, A-B-A, B-A-B-A, (A-B
(- ₄ Si, A-B-A-B-A, etc.) This hydrogenated block copolymer is a vinyl aromatic compound-conjugated diene compound block copolymer having a structure such as A-B-A-B-A. A polymer block A containing 5 to 60% by weight, preferably 10 to 40% by weight of a group compound, and further referring to the block structure, is a polymer block A mainly composed of vinyl aromatic compounds.
is a vinyl aromatic compound polymer block or
Preferably more than 50% by weight of vinyl aromatic compounds
It has a structure of a copolymer block of a vinyl aromatic compound containing 70% by weight or more and a hydrogenated conjugated diene compound, and further has a polymer block B mainly composed of a hydrogenated conjugated diene compound. is a hydrogenated conjugated diene compound polymer block, or a conjugate of a hydrogenated conjugated diene compound containing more than 50% by weight, preferably 70% by weight or more, and a vinyl aromatic compound. It has a polymer block structure. In addition, polymer block A mainly composed of these vinyl aromatic compounds and polymer block B mainly composed of hydrogenated conjugated diene compounds are composed of hydrogenated conjugated diene in the molecular chain of each polymer block. The distribution of the compound or vinyl aromatic compound may be random, tapered (monomer component increases or decreases along the molecular chain), partially block-like, or any combination thereof, and the vinyl aromatic compound In the case where there are two or more polymer blocks mainly consisting of a hydrogenated conjugated diene compound and two or more polymer blocks mainly consisting of a hydrogenated conjugated diene compound, each block may have the same structure or may have a different structure. good. As the vinyl aromatic compound constituting the hydrogenated block copolymer, one or more kinds are 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, the 1,2-vinyl bond structure is 10
~80%, preferably 25-65%. The number average molecular weight of the hydrogenated block copolymer is
The range is 5,000 to 1,000,000, preferably 10,000 to 800,000, more preferably 30,000 to 300,000, and the molecular weight distribution (ratio of weight average molecular weight to number average molecular weight) is 10.
It is as follows. The molecular structure of the hydrogenated block copolymer provided in the present invention may be linear, branched, radial, or any combination thereof. It doesn't matter if it can be obtained by any method. For example, by the method described in Special Publication No. 40-23798,
A vinyl aromatic compound-conjugated diene compound block copolymer is synthesized in an inert solvent using a lithium catalyst or the like, and then the method described in, for example, Japanese Patent Publication No. 42-8704 or Japanese Patent Application Laid-open No. 133203-1983. can be synthesized by hydrogenation in an inert solvent in the presence of a hydrogenation catalyst. In this case, 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 morphologically olefinic. The compound can be converted into polymer block B. In addition, regarding the hydrogenation rate of aromatic double bonds based on the vinyl aromatic compound copolymerized into block A mainly consisting of a vinyl aromatic compound and, if necessary, polymer block B mainly consisting of a conjugated diene compound. Although there is no particular restriction, it is preferable that the hydrogenation rate be 20% or less. The amount of unhydrogenated aliphatic double bonds contained in the hydrogenated block copolymer can be easily determined using an infrared spectrophotometer, nuclear magnetic resonance apparatus, or the like. The modified hydrogenated block copolymer bonded with molecular units containing carboxylic acid groups or derivative groups thereof used as component (b) is a hydrogenated block copolymer having the above-mentioned structure with α,β-unsaturation. Carboxylic acid or its anhydride, ester, etc. (hereinafter referred to as
(abbreviated as α,β-unsaturated carboxylic acids) in the presence or absence of an organic peroxide, and the reaction may be carried out in either a molten state or a solution state. In addition, the modified hydrogenated block copolymer contains, per 100 parts by weight of the hydrogenated block copolymer,
Those to which 0.05 to 10 parts by weight of α,β-unsaturated carboxylic acids are added can be used as component (b) of the present invention. Addition amounts other than this do not give favorable results regarding the thickening properties and phase separation of the resulting unsaturated polyester resin composition after compounding. 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, addition amounts outside these ranges are not preferable because the resulting cured product will have non-uniformity in surface characteristics and physical properties. Here, examples of α,β-unsaturated carboxylic acids that can be used in the grafting reaction include maleic acid, maleic anhydride, fumaric acid, itaconic acid, acrylic acid, acrylic ester, crotolic acid, cis-4 -cyclohexene-1,2-dicarboxylic acid and its anhydride, endocys-bicyclo[2,2,1]-5-heptene-2,3-dicarboxylic acid and its anhydride, maleimide, etc. Among them, maleic anhydride is preferred. Examples of organic peroxides include dicumyl peroxide, di-tert-butyl peroxide, tert-butylcumyl peroxide, 2,5-dimethyl-2,5-di(tert-butylperoxy)hexane, and dicumyl peroxide. , 5-dimethyl-2,5-di(tert-butylperoxy)hexyne-3, n-butyl-4,4-bis(tert-butylperoxy)valerate, 1,1-bis(tert-butylperoxy)
-butylperoxy)3,3,5-trimethylcyclohexane, etc., and can be suitably selected from these. The method for producing the modified hydrogenated block copolymer is not particularly limited in the present invention, but the modified hydrogenated block copolymer obtained may have a structure deviating from the above-mentioned characteristics,
Production methods that include undesirable components such as gel or that significantly increase the melt viscosity and deteriorate processability are not preferred. An example of a preferred production method is to melt-knead the hydrogenated block copolymer, α,β-unsaturated carboxylic acids, and organic peroxide described above at a temperature of 150 to 350°C in an extruder, and then radically modify the copolymer. There is a way. The obtained modified hydrogenated block copolymer may be ionomerized with a monovalent or higher valent metal ion. Furthermore, in the modified hydrogenated block copolymer thus obtained, unreacted α,β-unsaturated carboxylic acids or derivatives thereof generally remain as unreacted substances; The object may be removed completely or left in place. Next, the modified block copolymer used as component (c) of the present invention consists of a polymer block A mainly composed of at least one vinyl aromatic compound and a polymer block A mainly composed of at least one conjugated diene compound. This is a modified block copolymer (hereinafter abbreviated as "modified block copolymer") in which a molecular unit containing a carboxylic acid group or its derivative group is bonded to a block copolymer consisting of a combined block B. Here, the block copolymer is, for example, A-
B, A-B-A, B-A-B-A, (A-B)-
₄ A vinyl aromatic compound-conjugated diene compound block copolymer having a structure such as Si, A-B-A-B-A, etc. Modification and hydrogenation of the modified hydrogenated block copolymer used as component (b) Any material can be used as the block copolymer as long as it satisfies the above-mentioned requirements. However, if the polymer block mainly composed of a conjugated diene compound is, for example, a polymer block mainly composed of butadiene, the 1,2-vinyl bonds may be 70% or less. The modified block copolymer bonded with a molecular unit containing a carboxylic acid group or its derivative group used as component (c) is a block copolymer having the above-mentioned structure combined with an α,β-unsaturated carboxylic acid or its derivative. It is obtained by grafting anhydrides, esters, etc. (hereinafter abbreviated as α,β-unsaturated carboxylic acids) in a molten or solution state with or without the use of a radical initiator. . Regarding its manufacturing method,
Although not particularly limited in the present invention, methods in which the obtained modified block copolymer contains undesirable components such as gel, or in which its fluidity is reduced and processability is deteriorated are not preferred, such as extrusion. A preferred method is to add additives such as antioxidants in a machine or the like and carry out the modification reaction under melt-mixing conditions that substantially do not generate radicals. The modified block copolymer that can be provided as component (c) of the present invention is a block copolymer.
Per 100 parts by weight, 0.05 to 10 parts by weight of α,β-unsaturated carboxylic acids are added. Addition 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. This gives a compound with a much higher viscosity than the viscosity at the time of preparation, making it difficult to mold, which is undesirable. Therefore, addition amounts outside these ranges are not preferable because the resulting cured product will have non-uniformity in surface characteristics and physical properties. Here, as the α,β-unsaturated carboxylic acids that can be used in the grafting reaction of the block copolymer, the α,β-unsaturated carboxylic acids used in the graft modification reaction of the hydrogenated block copolymer described above It can be arbitrarily selected from carboxylic acids, and among these, maleic anhydride is preferred. The obtained modified block copolymer may be ionomerized with a monovalent or higher valent metal ion, and further,
Unreacted α,β-unsaturated carboxylic acids may remain unreacted in the modified block copolymer or may be completely removed. The vinyl monomer used as component (d) in the present invention acts as a crosslinking component. Examples of vinyl monomers include styrene, various substituted products of styrene, such as α-methylstyrene, vinyltoluene, dimethylstyrene, trimethylstyrene, halogenated styrene, tert-butylstyrene, styrene sulfonate, aminostyrene, P-benzylstyrene,
Vinyl aromatic compounds such as P-phenoxystyrene, acrylic acid or methacrylic acid and aliphatic alcohols such as methyl alcohol, ethyl alcohol, propyl alcohol, octyl alcohol, hexanol, tetrahydrofurfuryl alcohol, ethylene glycol, propylene glycol, etc. esters, acrylic acid or methacrylic acid derivatives such as 2-aminoethyl-methacrylate, N,N-diethylamino-acrylate, N,N-diethylamino-methacrylate, α, such as maleic acid, fumaric acid, crotonic acid, itaconic acid, etc. β-unsaturated dicarboxylic acids or their anhydrides, esters, amides, imides, etc., fumaric acid esters such as diethyl- and dioctyl fumarate, as well as various vinyl and vinylidene monomers, such as acrylonitrile, methacrylonitrile, acetic acid. Vinyl, vinyl chloride, vinylidene chloride, vinylene carbonate, vinyl-2
-chloroethyl ether, _C8 - _C18 alkyl vinyl ether, vinyl ester of _C8 - _C18 fatty acid, 2-vinylfuran, vinylphenol, vinylphenyldisiloxane, 2-vinylpyridine,
4-vinylpyridine, vinylpyrrole, vinylpyrrolidone, vinylsulfonic acid, vinylurethane,
Examples include methylvinylketone-2-vinylquinoline and vinylcarbazole. Also, 1,3
- Conjugated diene compounds such as butadiene, isoprene, piperylene, methylpentadiene, chloroprene, and 2-methoxybutadiene and 1
Alkoxy- and cyano derivatives of conjugated dienes such as -cyanobutadiene can also be used. moreover,
Polyfunctional crosslinkable vinyl monomers 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:
Examples include styrene, vinyltoluene, α-methylstyrene, chlorostyrene, divinylbenzene, methyl methacrylate, methyl acrylate, diallyl phthalate, and triallyl cyanurate. The curing agent as component (e) used in the present invention is:
Organic peroxides, organic hydroperoxides and azo compounds can be used. Some peroxides useful in this invention include dialkyl peroxides and diacyl peroxides. Alkyl peroxide has the general structure R-OO-
R', where R and R' are the same or different primary, secondary or tertiary alkyl, cycloalkyl, aralkyl or heterocyclic groups. Groups of peroxides suitable for use in the present invention include dicumyl peroxide, di-tert-
Included are butyl peroxide, tert-butylcumyl peroxide and 2,5-dimethyl-2,5-bis(tert-butylperoxy)hexane. Diacyl peroxide has the general structure RC(O)
OOC(O)R', in which R and R' are the same or different alkyl groups, cycloalkyl groups,
It is an aralkyl group, an aryl group or a heterocyclic group. Examples of some diacyl peroxides suitable for use in the present invention include dilauroyl peroxide, dibenzoyl peroxide, dicetyl peroxide, didecanoyl peroxide, di-(2,4-dichlorobenzoyl) peroxide, There are diisononanoyl peroxide and 2-methylpentanoyl peroxide. Additionally, 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 peroctoate and tert-butyl perbenzoate. Examples of hydroperoxides suitable for use in the present invention include tert-butyl hydroperoxide, cumyl hydroperoxide, 2,5-
These include dimethyl-2,5-dihydroperoxyhexane, P-methane 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(iso butyronitrile). The blending ratio of each component constituting the composition of the present invention is 10 to 90 parts by weight, preferably 20 to 80 parts by weight of component (a) to 100 parts by weight of the total amount of components (a) to (d), More preferably 20 to 60 parts by weight, and the total amount of components (b) and (c) is 2 to 70 parts by weight, preferably 5 parts by weight.
It is necessary that the amount is 50 parts by weight, more preferably 5 to 40 parts by weight, and that component (b)/component (c) = 0.11 to 9 (weight ratio). If this ratio is less than 0.11, the initial viscosity of the compound will be low, the fluidity during heating will be high, and the glass fibers will be unevenly dispersed, making it impossible to obtain a homogeneous molded product. On the other hand, if the ratio exceeds 9, the initial viscosity of the compound will be too high and excessive shear will be applied during kneading, resulting in undesirable cutting of glass fibers, or damage to fillers and glass fibers during the coating impregnation process. Since surface wetting becomes insufficient, a molded article with improved surface properties cannot be obtained. Therefore, it is necessary to keep this ratio within the above range, and this results in a compound viscosity of around 400,000 to 600,000 poise for BMC.
In SMC, a cured product of an unsaturated polyester resin composition having excellent surface smoothness, surface gloss, dimensional stability, and impact resistance is obtained when molded under conditions of applying approximately 0 to 300,000 poise. Next, component (d) is 10 to 80 parts by weight, preferably 20 to 80 parts by weight.
In the range of 70 parts by weight. Further, the amount of the curing agent used in the present invention is 0.1 to 10 parts by weight, preferably 0.3 to 5 parts by weight, more preferably 0.5 to 3 parts by weight, based on the total of 100 parts by weight of components (a) to (d).
Parts by weight. Other additives such as thickeners, fiber reinforcing agents, inorganic fillers, low shrinkage agents, pigments, colorants, lubricants, mold release agents, etc. may be added to the composition of the present invention as necessary. Can be done. The thickeners used in the present work are oxides and/or hydroxides of metals from groups of the periodic table, such as magnesium, calcium,
Selected from strontium, barium and zinc oxides and hydroxides. Preferred are magnesium and/or calcium oxides or hydroxides. The above-mentioned thickener is added to components (a), (b), (c), and (d) of the composition of the present invention at 0.5 parts by weight per 100 parts by weight in total.
It is used in an amount of ~10 parts by weight, preferably 1 to 5 parts by weight. The fiber reinforcing agent used in the present invention includes glass, metal,
Silicate, asbestos, cellulose, carbon, graphite, polyester, polyacrylic, polyamide,
Selected from fibers such as polyolefin. Preferred is glass fiber. The above fiber reinforcing agent comprises component (a) of the composition of the present invention,
It is used in an amount of 5 to 300 parts by weight, preferably 20 to 200 parts by weight, and more preferably 20 to 100 parts by weight, based on a total of 100 parts by weight of components (b), (c), and (d). The filler used in the present invention is preferably an inorganic particulate filler, such as calcium carbonate, calcium silicate, silica, calcined clay, chalk, talc, limestone, anhydrous calcium sulfate, barium sulfate, asbestos,
Selected from powdered glass, quartz, aluminum hydrate, aluminum oxide, antimony oxide, etc. The above filler is component (a) of the composition of the present invention, and (b)
For a total of 100 parts by weight of component, component (c), component (d)
It is used in an amount of 50 to 800 parts by weight, preferably 100 to 400 parts by weight, and more preferably 100 to 300 parts by weight. Low shrinkage agents that can be used in the present invention include:
Polystyrene-based, poly(meth)acrylate-based,
It is selected from homopolymers or copolymers such as polyvinyl acetate-based, polyvinyl chloride-based, polyethylene-based, polypropylene-based, polyamide-based, polycarbonate-based and cellulose-based polymers.
The main copolymers include methyl methacrylate,
Examples include homopolymers of ethyl methacrylate, butyl methacrylate and ethyl acrylate, and copolymers of methyl methacrylate and acrylic acid and methacrylic acid and/or lower alkyl esters thereof. For example, lauroyl methacrylate, isobornyl methacrylate, acrylamide, hydroxyethyl methacrylate, styrene, 2-ethylhexyl methacrylate, acrylonitrile, methacrylic acid, methacrylamide,
Examples include copolymers of methyl methacrylate containing a small amount of one or more of methyloyl acrylamide and cetylstearyl methacrylate. Other useful copolymers include styrene-acrylonitrile, vinyl chloride-vinyl acetate, and the like. These low shrinkage agents are used in an amount of 0 to 40 parts by weight, preferably 2 to 40 parts by weight, based on a total of 100 parts by weight of components (a), (b), (c) and (d) of the composition of the present invention. It is used in amounts ranging from 20 parts by weight. In addition to the above, the composition of the present invention may also contain, for example, pigments, colorants, lubricants or mold release agents, stabilizers, silane coupling agents, flame retardants, and the like.
Specific examples of pigments include titanium oxide, carbon black, and phthalocyanine. Examples of lubricants or mold release agents include aluminum, calcium, magnesium, and zinc salts of stearic acid. Stabilizers include pallium, tin octoate, tris (nonylphenyl) phosphite, alkyl phenols such as BHT, quinones,
There are amines, etc. 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 as the component (a) of the present invention and a vinyl monomer as the component (d), a modified hydrogenated block copolymer as the component (b), and (c) The component modified block copolymer and
(d) A second mixture containing the vinyl monomer as the component is mixed, and at this time, either or both of the first mixture and the second mixture is mixed with a curing agent and, if necessary, a filler and fiber reinforcement. This manufacturing method involves mixing additives such as a thickener, a thickener, a low shrinkage agent, and a mold release agent. In particular, it is preferable to mix the filler into the second mixture. This method is preferred for suppressing phase separation between the modified hydrogenated block copolymer and the unsaturated polyester resin. The unsaturated polyester resin composition of the present invention described above 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. (Effects of the Invention) The present invention improves the initial viscosity of the compound by setting the component (b) and the component (c) at a specific blending ratio, and reduces the decrease in viscosity during heating, and improves surface properties and dimensions. It can provide an unsaturated polyester resin composition with excellent stability and impact resistance, and its fields of use include automobile parts, transportation equipment such as boats, construction equipment such as bathtubs and septic tanks, and other products such as chairs. Can be useful for industrial supplies. (Examples) In order to explain the present invention in more detail, Examples will be described, but the present invention is not limited thereto. (1) Preparation of unsaturated polyester resin as component (a) A mixture consisting of 0.7 mol of maleic anhydride, 1.4 mol of phthalic anhydride, 2.0 mol of propylene glycol, and 0.2 mol of diethylene glycol was heated to about 100°C under a nitrogen stream, While stirring and removing condensed water from the system, gradually raise the temperature to approximately 210°C.
An esterification reaction was carried out at this temperature to synthesize an unsaturated polyester resin with an oxidation rate 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 component (a-1). Furthermore, a mixture consisting of 0.6 mol of isophthalic acid, 0.6 mol of phthalic anhydride, 1.4 mol of maleic anhydride, and 2.6 mol of propylene glycol was subjected to an esterification reaction in the same manner as above, and 30 mol of oxidized
An unsaturated polyester resin was synthesized. This unsaturated polyester resin was dissolved in styrene, and a solution having a solid content concentration of 65% by weight was used as component (a-2). (2) Synthesis of modified hydrogenated block copolymer of component (b) Hydrogenated polybutadiene-polystyrene-
It has a hydrogenated polybutadiene-polystyrene structure, with a bound styrene content of 18% by weight, a 1,2-vinyl bond content of the polybutadiene portion before hydrogenation of 40%, a number average molecular weight of 56000, and a molecular weight distribution.
1.04, a hydrogenated block copolymer with a hydrogenation rate of 98% was synthesized using a Ti-based hydrogenation catalyst described in JP-A-59-133203. This hydrogenated block copolymer 100
Per part by weight, maleic anhydride 1 part by weight, 2,5
-Dimethyl-2,5-di(tert-butylperoxy)hexane was mixed with 0.1 part by weight, and a modification reaction was carried out in a 50 mm diameter twin screw extruder set at 250°C. The obtained modified hydrogenated block copolymer contained 0.75 parts by weight of maleic anhydride. This product was dissolved in styrene to obtain a solution (b-1) component with a solid content concentration of 30% by weight. Next, it has a (polystyrene-hydrogenated polybutadiene) - ₄ Si structure, the amount of bound styrene is 30% by weight, the amount of 1,2-vinyl bonds in the polybutadiene part before hydrogenation is 60%, and the number average molecular weight
93,000, a molecular weight distribution of 1.48, and a hydrogenation rate of 97%, a hydrogenated block copolymer was synthesized using a Ti-based hydrogenation catalyst described in JP-A-59-133203. Per 100 parts by weight of this hydrogen block copolymer, 0.5 parts by weight of maleic anhydride, 0.1 parts by weight of dicumyl peroxide, and 0.2 parts by weight of magnesium hydroxide are mixed,
The modification reaction was carried out using a 40 mm diameter single screw extruder at a temperature of 230°C. The obtained modified hydrogenated block copolymer had 0.16 parts by weight of maleic anhydride added thereto. This product was dissolved in styrene, and a solution having a solid content concentration of 30% by weight was used as component (b-2). Furthermore, it has a structure of polystyrene-hydrogenated polybutadiene-polystyrene, the amount of bound styrene is 30%, the amount of 1,2-vinyl bonds in the polybutadiene part before hydrogenation is 32%, the number average molecular weight is 44,000, the molecular weight distribution is 1.05, and the amount of bonded styrene is 30%. A hydrogenated block copolymer with an addition rate of 99% was synthesized using a hydrogenation catalyst described in JP-A-59-133203. Per 100 parts by weight of this hydrogenated block copolymer, 3.0 parts by weight of maleic anhydride and 0.3 parts by weight of n-butyl 4,4-bis(tert-butylperoxy)valerate were mixed.
The modification reaction was carried out at a temperature of 260°C using a mm-diameter twin-screw extruder. The obtained modified hydrogenated block copolymer had 2.1 parts by weight of maleic anhydride added thereto. This product was dissolved in styrene, and a solution with a solid content concentration of 30% by weight was used as component (b-3). (3) Synthesis of modified block copolymer of component (c) (polystyrene-polybutadiene) - has a structure of ₄ Si, the amount of bound styrene is 18% by weight, the amount of 1,2-vinyl bonds in the polybutadiene part is 42%, A block copolymer with a number average molecular weight of 75,000 and a molecular weight distribution of 1.34 was synthesized. Per 100 parts by weight of this block polymer, 1 part by weight of maleic anhydride, stabilizer
1.5 parts by weight were mixed and a modification reaction was carried out in a 50 mm diameter twin screw extruder set at 240°C. The obtained modified block copolymer contained 0.03 parts by weight of maleic anhydride. This product was dissolved in a styrene solution, and a solution with a solid content concentration of 30% by weight was prepared (c-
1) As a component. Next, it has a polystyrene-polybutadiene-polystyrene structure, with 40% by weight of bound styrene, 36% of 1,2-vinyl bonds in the polybutadiene part, number average molecular weight of 69,000, and molecular weight distribution of 1.05.
A block copolymer was synthesized. 2 parts by weight of maleic anhydride and 1.5 parts by weight of a stabilizer were mixed per 100 parts by weight of this block copolymer, and a modification reaction was carried out in a 30 mm diameter twin screw extruder set at 260°C. The obtained modified block copolymer contained 0.4 parts by weight of maleic anhydride. Dissolve this material in a styrene solution, and the solid content concentration is 30% by weight.
The solution was used as component (c-2). Furthermore, it has a polybutadiene-polystyrene-polybutadiene-polystyrene structure, with a bound styrene content of 20% by weight, a 1,2-vinyl bond in the polybutadiene portion of 12%, and a number average molecular weight.
A block copolymer with a molecular weight distribution of 83,000 and a molecular weight distribution of 1.04 was synthesized. 3 parts by weight of maleic anhydride and 1.5 parts by weight of a stabilizer were mixed per 100 parts by weight of this block copolymer, and a modification reaction was carried out in a 50 mm diameter twin screw extruder set at 250°C. The obtained modified block copolymer contained 0.7 parts by weight of maleic anhydride. This product was dissolved in a styrene solution to obtain a solution (c-3) component with a solid content concentration of 30% by weight. (4) Component (d) is styrene in which the above-mentioned components (a) to (c) are dissolved. (5) Tert-butyl peroxybenzoate as component (e) was used. Examples 1 to 4, Comparative Examples 1 to 2 Styrene solution of unsaturated polyester resin (a), styrene solution of modified hydrogenated block copolymer (b), styrene solution of block copolymer (c), tert-butyl Peroxybenzoate (e), zinc stearate, calcium carbonate, and magnesium oxide were blended according to the formulation shown in Table 1 to obtain a compound before curing. 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 Bruckfield viscometer HBT type.
The results are listed in Table 1. From these results, it was 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.

【table】

[Table] Examples 5 to 8, Comparative Examples 3 to 4 Glass fiber (PPG-3198; manufactured by PPG) was added to each of the basic formulations of Examples 1 to 4 and Comparative Examples 1 to 2.
SMC was prepared by blending 100 parts of the following, and the mixture was aged at 40°C for 48 hours. Thereafter, it was pressure-molded at 140°C and 85 kg/m ² 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 a surface smoothness with "large undulations".
And "small waviness" was not observed at all, and the surface gloss was 60% or more, indicating excellent surface properties. It was also found that the shrinkage rate during molding was negative (expansion), and that it had excellent effects as a low shrinkage rate. On the other hand, it has become clear that the unsaturated polyester resin composition of the present invention is poor in the balance of surface smoothness, surface gloss, and low shrinkage.

【table】

Claims (1)

[Scope of Claims] 1 (a) Unsaturated polyester resin (b) Polymer block A mainly composed of at least one vinyl aromatic compound and polymer block B mainly composed of at least one conjugated diene compound. Hydrogenating a block copolymer consisting of
A modified hydrogen block in which a molecular unit containing a carboxylic acid group or its derivative group is bonded to a hydrogenated block copolymer in which at least 80% of the aliphatic double bonds based on a conjugated diene compound in the copolymer are hydrogenated. Copolymer (c) 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, in which a carboxylic acid group is added. 1. An unsaturated polyester resin composition comprising: (d) a modified block copolymer to which molecular units containing or derivative groups thereof are bonded; (d) a vinyl monomer; (e) a curing agent.