AU628192B2 - Hardenable unsaturated polyester resin compositions - Google Patents

Description

-1-628192 COMMONWEALTH OF AUSTRALIA PATENT ACT 1952 COMPLETE SPECIFICATION (Original) FOR OFFICE USE o *o Int. Class Application Number: Lodged: Class Complete Specification Lodged: Accepted: Published: Priority: Related Art: Name of Applicant: Address of Applicant: Actual Inventor(s): Address for Service:

TAKEMOTO

KAISHA

YUSHI KABUSHIKI 2-5 Minato-Machi, Gamagori-shi, Aichi-ken, Japan Yuji TAKAYAMA Mitsuo KINOSHITA Shigeru IMAMURA Hirokazu MATSUEDA DAVIES COLLISON, Patent Attorneys, of 1 Little Collins Street, Melbourne, 3000.

Complete specification for the invention entitled: "Hardenable Unsaturated Polyester Resin Compositions" The following statement is a full description of this invention, including the best method of performing it know to us:- (A member of the firm of Davies Collison Cave for and on behalf of the applicant) 920702,EEDAT.035,A:\59012TAK.RES,1 -I ,=,No Y i I, -2- HARDENABLE UNSATURATED POLYESTER RESIN COMPOSITIONS 0 0 a 0 0 0 00-44O 04.

o 0 0 00 0 00c 0 04000 0 0 00 000 0 0 0 Or.O 40 Background of the Invention This invention relates to hardenable unsaturated polyester resin compositions.

Hardenable unsaturated polyester resin compositions are widely used not only as sheet molding compound (SMC) and bulk molding compound (BMC) but also for wet molding methods such as the so-called matched die method as well as the RIM method which is a method of injecting resin.

Thermosetting unsaturated polyester resins are known to have large molding shrinkage as they harden at the time of molding. In order to improve the accuracy in measurements as well as other physical characteristics such as impact strength of their molded products, it has been common practice to add thermoplastic high-molecular compounds to such unsaturated polyester compounds. If these compounds are simply mixed together to make a composition, however, the surface quality of its molded products becomes extremely poor and desired levels of improvement in reducing shrinkage and increasing impact strength can hardly be attained. Moreover, such compositions have poor workability in molding processes because they generally do not have sufficient compatibility and/or dispersibility.

According to a widely used conventional method, carboxyl groups are introduced into the molecules of high-molecular compounds to be added to thermosetting unsaturated polyester resins so as to combine these carboxyl 900713,csspe.001,hardrei.spe,2 i -3groups with the carboxyl end groups of the thermosetting unsaturated polyester resins through an oxide or hydroxide of an alkaline earth metal such as magnesium oxide. Some effects are observed in this case if one uses, as the high-molecular compound to be added, a copolymer of methacrylic acid or acrylic acid and methyl methacrylate, vinyl acetate or styrene. With compositions of this kind, however, one can hardly expect any improvement in physical characteristics of the type mentioned above for their molded products.

In order to improve the impact strength of molded products, one may think of diene polymers as the high-molecular compounds to be added. If such compounds are used in a similar manner, however, lustre spots become S" conspicuous on the surface of the molded products obtained from such comoositions. Such products are inferior also in other physical characteristics, showing no advantageous effects of introducing carboxyl groups into diene o. polymers. Although diene polymers with carboxyl groups in them are soluble in a styrene monomer which is a monomer component used for hardenable unsaturated polyester resin compositions, they separate into layers extremely quickly if there is in coexistence an alpha, beta-ethylenically unsaturated polyester or the like. This is probably because compatibility and/or t. .dispersibility is so poor between diene polymers with carboxyl groups and thermosetting unsaturated polyester resins that, even if magnesium oxide or the like is added to them, a large portion of them becomes separated before their combination through salification, thereby preventing improvement of the physical characteristics of molded products.

In order to improve compatibility and dispersibility with thermc setting unsaturated polyester resins, compositions containing block copolymers with polystyrene block have been considered (Japanese Patent Publications Tokkai 53-74592 and 60-99158). Although they do succeed to some extent in improving compatibility and dispersibility, molded products obtained from these compositions are inferior regarding molding shrinkage and in particular regarding impact strength because use is made of block copolymers depending 900713,csspe.OO1,hardresspe,3 -4on polystyrene which is basically not sufficiently tough.

Summary of the Invention It is therefore an object of the present invention to provide hardenable unsaturated polyester resin compositions which have sufficient compatibility and/or dispersibility as well as superior workability in molding processes and are capable of providing improved physical characteristics such as surface appearance, mold shrinkage and impact strength to their molded products.

The present invention is based on the discovery made by the present inventors that the aforementioned and other objects of the present invention are attained by compositions obtained by causing thermosetting unsaturated polyester resins to contain block copolymers having as segments polyester parts and liquid rubber parts.

Detailed Description of the Invention In summary, the present invention relates to hardenable unsaturated polyester resin compositions comprising block copolymer having as their constituent segments polyester blocks and liquid rubber block and unsaturated polyesters.

a o S. J The present invention provides a hardenable unsaturated polyester resin composition comprising S.0 a block copolymer having one or more polyester blocks formed by starting with carboxyl group or hydroxyl group in liquid rubber compound and 8 25 by alternate condensation thereof with organic dicarboxylic anhydride and 1,2-epoxide in the presence of a catalyst and liquid rubber compound block formed from monomers selected from the group consisting of butadiene, ,isoprene, chloroprene and 1,3-pentadiene as constituent segments thereof, and unsaturated polyester.

Preferred block copolymers are of the form X--Y)n where X is polybutadiene block or hydrogenated polybutadiene block, Y is polyester block having connected by ester linkage one or more -/47 z 920702,EEDAT.035,A:\59012TAK.RES,4 f v 4,s. a types of organic dicarboxylic anhydrides selected from the group consisting of phthalic anhydride, succinic anhydride, cyclohexane dicarboxylic anhydride, cyclohexene dicarboxylic anhydride and methylene cyclohexane dicarboxylic anhydride and one or more types of 1,2-epoxide selected from the group consisting of ethylene oxide, propylene oxide and butylene oxide, n is an integer equal to or greater than 1, and is formed by starting with carboxyl group or hydroxyl group in polybutadiene or hydrogenated polybutadiene and by alternate condensation of said organic dicarboxylic anhydride and said 1,2-epoxide therewith in the presence of a catalyst.

The aforementioned block copolymers of the present invention can be obtained stably in an industrially advantageous manner by starting with a liquid rubber compound having within its molecule one or more active hydrogen group such as hydroxyl group and carboxyl group and causing it to react alternawly with an organic dicarboxylic anhydride and 1,2-epoxide in the presence of a catalyst, thereby forming polyester chains by condensation through the active hydrogen groups of the liquid rubber compound.

Aternatively, they may be obtained by starting wi:h a liquid rubber comp-und-^F 0. having within its molecule one or more hydroxyl groups and fo polyester chains through the hydroxyl groups of the li er compound through o. sequential ring-opening ymeriation of epsilon-lactone in the presence of a catalyst. e-yester chains may also be connected to a liquid rubber 00 mpoud cither directly or indirectly by using a erosslinking agent.

0 What is impo:tant about the block copolymers of the present invention is that they have as their constituent segments both polyester block and liquid rubber block. The present invention, therefore, is not limited by the method of liquid rubbers production or their specific structure. For example, the active hydrogen groups in a liquid rubber compound may be either inside or at the end of a chain. They may be connected to a chain either directly or indirectly through any groups of atoms. As for the liquid rubber compounds which form -6segments, their stereoisomerism and structural isomerism according to their method of polymerization such as group polymerization, ion polymerization and living polymerization do not limit the scope of the present invention.

Examples of monomer diene compounds forming liquid rubber compounds include butadiene, isoprene, chloroprene and 1,3-pentadiene. Examples of liquid rubber compounds which can be used advantageously in the present invention include alpha, omega-1, 2-polybutadiene glycol (Nisso PB-G series produced by Nippon Soda, Inc.), alpha, omega-1, 2-polybutadiene dicarboxylic acid (Nisso PB-C series produced by Nippon Soda, Inc.), alpha, omega-1, 2polybutadiene glycol mono-malate (Nisso PB-GM series produced by Nippon Soda, Inc.), end carboxyl modified 1, 4-polybutadiene (Hycar CTB series produced by Ube Kosan, Inc. or B.F.Goodrich, Inc.), end hydroxyl group S modified 1,4-polybutadiene (Poly-bd R-45M or R-45HT produced by Idemitsu Sekiyu Kagaku, Inc. or Arco Chemical, Inc.) and those obtained by either ll partially or wholly hydrogenating the aforementioned compounds such as hydrogenated alpha, omega-1, 2-polybutadiene glycol (Nisso PB-GI series produced by Nippon Soda, Inc.) and hydrogenated alpha, omega-1, 2polybutadiene dicarboxylic acid (Nisso PB-CI series produced by Nippon Soda, Inc.). Also acceptable are compounds obtained by hydroxyalkyl esterification by addition of alkylene oxide to the carboxyl group of carboxy modified liquid i, rubber compound and compounds obtained by reaction between the epoxy group of epoxy modified liquid rubber compound and water, alcohol or monoatomic organic acid to open the ring of the epoxy group.

t t 4 L t Sl Examples of organic dicarboxylic anhydride used in the aforementioned examples of production processes include aliphatic dicarboxylic anhydrides such as succinic anhydride mneied a-hydride-and alkenyl succinic anhydride, aromatic dicarboxylic anhydrides such as phthalic anhydride and naphthalene dicarboxylic anhydride and alicyclic dicarboxylic anhydrides such as cyclohexane dicarboxylic anhydrides, cyclohexene dicarboxylic anhydride and end methylene cyclohexene dicarboxylic anhydrides. Examples of 1, 2-epoxides 0 -7in the same examples of production processes include ethylene oxide, propylene oxide and 1,2-butylene oxide. Examples of catalysts in still the same examples of production processes include lithium halides such as lithium chloride and lithium bromide and tetra-alkyl quaternary ammonium salts such as tetramethyl ammonium brormide, tributylmethyl ammonium bromide and tetrapropyl ammonium chloride.

Examples of cpsikn aliphatic lactone in the aforementioned ring polymerization of epsilon-aliphatic lactone for the formation of polyester chains in liquid rubber compounds include epsiion-caprolactone. ples of catalyst used for sequential ring-opening polymerization of silon-aliphatic 9 lactone to hydroxyl groups which exist as functional oups of liquid rubber compounds include anionic polymerization c ysts, coordination anionic polymerization catalysts and cationic ymerization catalysts, as described in b. a "Lectures on the Theories of ymerization Reactions, Vol.7, Ring-Opening Polymerization II" (pu 'shed by Kagaku Dojin) at page 108. In particular, titanate catal such as tetrabutyl titanate, tetrapropyl titanate and tetraethyl titanat nd tin catalysts such as dibutyltin oxide, tin octylate and stannous Q oioride. It goes without saying that none of the examples disclosed above is intended to limit the-seope-ef-4t-he-present-invention.

The idea which is basic to the present invention is to use block copolymers with polyesters combined to liquid rubber compounds as segments in order to improve .patibility and/or dispersibility of liquid rubber compounds with therm ding unsaturated polyester resins while retaining the original characteristics of these liquid rubber compounds. The polyester segments in these block copolymers can be selected appropriately in view of the type of thermosetting unsaturated polyester resin which is used together. In general, poly-(propylene glycol phthalate), poly-(ethylene glycol phthalate-succinate) and poly-(butylene glycol succinate) are considered for polyester segments because they are compatible and dispersible with relatively many kinds of thermosetting unsaturated polyester resins. In some situations, it is effective to 900713,csspe001,bardresLspe,7 2- P -8include unsaturated groups based on alpha, beta-ethylenically unsaturated dicarboxylic acid within the polyester segments.

Tests on compatibility and dispersibility with thermosetting unsaturated polyester resins will be described below. Even if compatibility and/or dispersibility of these resins with the block copolymers is not completely satisfactory, sufficient compatibility and/or dispersibility can be attained by making the terminal groups of the polyester blocks in the form of carboxylic acid and adding maganesium oxide, magnesium hydroxide or the like as a thickener. The terminal carboxylic acid group of the polyester blocks may be formed by the reaction of dicarboxylic acid anhydride with a terminal hydroxyl Sgroup of the polyester block. Examples of dicarboxylic acid anhydride which may preferably be used include succinic anhydride, phthalic anhydride and S their mixtures.

ao a If the terminal groups of the polyester segment chains are in the form of hydroxyl groups, a di-isocyanate such as methylene-di(4-phenyl isocyanate) may be used to sufficiently make up for the insufficiency in compatibility and/or a dispersibility.

a s a The ratio of polyester segments contained in the block copolymer also contributes to compatibility and dispersibility with thermosetting unsaturated polyester resins. In general, compatibility and dispersibility increase if the ratio of polyester segments is made higher. They decrease if the ratio is made lower.

a404sa In order to improve the impact strength and surface characteristics of the molded products, it is preferable to select polybutadiene or a polybutadienetype compound with copolymerization ratio of other monomers as low as possible as the liquid rubber compound in the block copolymer. In such a situation, the ratio of polyester segments within the block copolymer should be made as low as possible while compatibility and dispersibility with 9 0 0713,csspe.001,hardresLspe,8 |1 I 1 -9thermosetting unsaturated polyester resins are taken into consideration. If the main purpose is to improve the thermal strength of the molded products, or to lower the temperature-dependence of their shear and tensile strength while maintaining their surface characteristics, on the other hand, the ratio of polyester segments within the block copolymer should preferably be increased somewhat or unsaturated groups should additionally be mixed within the polyester segments. In general, the ratio of polyester segments within the block copolymer of the present invention should preferably be between 10 and weight The block copolymers of the present invention are generally used by making a 25-40% solution with a polymerizable monomer such as styrene monomer and a. mixing this solution at 20-50% with respect to thermosetting unsaturated I polyester resins. Depending on the kind of block copolymer, however, the ttoo aforementioned step of preparing a solution in a polymerizable monomer such S ,as styrene monomer may be omitted before it is added to thermosetting unsaturated polyester resins. In such a situation, an appropriate amount of polymerizable monomers may be added to the thermosetting unsaturated polyester resins before the block copolymer is added.

Examples of thermosetting unsaturated polyester resins which may be advantageously used in the present invention include not only condensation products of alpha, beta-ethylenically unsaturated dicarboxylic acid and glycols as well as modified unsaturated polyesters obtained by adding conjugated diene compounds to the unsaturated groups in these polyesters but also -novolac-type unsaturated polyesters and vinylester-type unsaturated polyesters.

The type of thermosetting unsaturated resins to be used, however, is not intended to limit the scope of the present invention. Polymerizable monomers such as styrene, methacrylates and diaryl phthalate may be considered as solvents for these resins. Styrene is usually used for this purpose. Those with the solid component adjusted to 60-65% are easy to use.

900713,c_sspe.001,hardresLspe,9 As explained above, styrene monomer is usually used as the solvent in the compositions embodying in the present invention but it may be replaced either wholly or partially by chlorostyrene monomer in order to make the molded products less flammable. In order to increase weather resistance of the molded products or to improve their surface lustre, a part of the styrene monomer may be replaced by methyl methacrylate. In addition to the above, many different kinds of polymerizable monomers can be included in the composition, depended upon the objects to be attained.

The simplest compositions embodying the present invention are mixtures of the aforementioned block copolymer and thermosetting unsaturated polyester resins. If the matched die method, the resin injection method (the RIM method), the hand lay-up method or the filament winding method is used for the molding, a small amount of curing catalyst or mold release agent may be .o appropriately added to such a simple composition. In such a situation, one or more known high-molecular compounds may also be added, if necessary. In addition to these so-called resins, premixed molding compositions such as SMC and BMC may contain calcium carbonate, etc. as a filler, oxides or hydroxides of alkaline earth metals and diisocyanates as thickener if necessary, metallic o soap as a mold release agent and glass fibers as a reinforcing agent. The mixing ratios and methods are not different from the case of known ,"Cr compositions.

In what follows, examples of block copolymers are described in order to more clearly explain the present invention but the present invention is not intended to be limited by these examples. Any modifications and variations based on the fundamental idea of the present invention as described above are intended to be included within the scope of this invention.

900713,csspe.00O1,hardresispe, -11 Examples Production: Example No. 1 Placed inside an autoclave were 52.3g (0.35 moles) of phthalic anhydride, 82.5g (0.825 moles) of succinic anhydride, and as catalysts 0.7g of lithium chloride and 715g (0.5 moles) of alpha, omega-1,2-polybutadiene glycol (Nisso PB- G1000 with average molecular weight of 1430 produced by Nippon Soda, Inc.).

After nitrogen gas was introduced into the reacting system, it was heated to 130oC with stirring. Next, 42.7g (0.74 moles) of propylene oxide was introduced over a period of one hour. The reaction was completed after two hours of aging at 130 and 890g of a yellowish transparent viscous liquid 0 product was obtained. The molecular weight of this polybutadiene-polyester o block copolymer thus obtained was 1786 (hereinafter always the calculated value) and the ratio of polyester blocks was 20.0 weight (hereinafter written simply as Its acid value was 27 and its hydroxyl value was 38.

Production: Example No. 2 Placed inside a flask were 800g (0.448 moles) of the block copolymer obtained Sin Example No.1 and 54.2g (0.54 moles) of succinic anhydride for a reaction at 120-125oC in a nitrogen gas flow for a period of two hours. After the contents were cooled to 500C, 214g of styrene monomer was added to prepare a styrene solution containing 80 weight of block copolymer. The acid value of this styrene solution containing the block copolymer was 50.7 and its hydroxyl S* value was 1.9. Polybutadiene-polyester block copolymer with carboxyl S* modified ends of polyester chains was obtained.

Production: Example No.3 Placed inside an autoclave were 165.5g (1.67 moles) of succinic anhydride, 105.2g (0.71 moles) of phthalic anhydride, 1430g (1 mole) of alpha, omega-1, 2-polybutadiene glycol (as used in Example No.1) and 0.6g of lithium chloride.

900713,c_sspe.001,hardresLspe,11 -12- After nitrogen gas was introduced into the reacting system, it was heated to 1030C with stirring. Next, 86.3g (1.49 moles) of propylene oxide was introduced over a period of 40 minutes at 125-1300C. The reaction was completed after two hours of aging at this temperature to obtain polybutadiene-polyester block copolymer. After this was cooled, 447g of styrene monomer was added to dissolve and dilute it and a styrene solution containing 80 weight of the aforementioned block copolymer was prepared.

The molecular weight of the polybutadiene-polyester block copolymer thus obtained was 1787 and the ratio of polyester blocks was 20%. The acid value of its styrene solution was 25.6 and its hydroxyl value was 26.3.

edaetien: ExampleNo.1 o, A mixture of 98g (1 mole) of maleic anhydride, 148g (1 mole) of phthali anhydride and 159.6g (2.1 moles) of propylene glycol was heated to within a nitrogen gas flow for a reaction. The condensation re ion was stopped when the acid value of the reacting system reache 0 to obtain unsaturated polyester. The numerical average molecu weight of this unsaturated polyester was 754 and its hydroxyl val was 89.3.

D 44 A mixture of 151g (0.2 moles) of the obt *ned unsaturated polyester and 300g I (0.1 mole) of alpha, omega-1, 2-poly tadiene glycol (Nisso PB-G3000 with numerical average molecular w eiht of 3000 produced by Nippon Soda, Inc.) was dissolved in 1000ml of ouene and then 50g (0.2 moles) of methylene-di(4phenyl isocyanate) was dded for a reaction at 500C for one hour with stirring.

Toluene was distil away under reduced pressure and a yellow viscous liquid product was o ained.

Wh as thus obtained as mainly a block copolymer with the hydroxyl oups in unsaturated polyester and alpha, omega-1, 2-polybutadiene glycol crosslinked together by methylene-di(4-phenyl isocyanate). Also included in part as by-product re c positions with unsaturated-plyesteos-er A Z? 007,3,c sspc.001,hardresLspe,12 S/x \C

~II:

O 0 0 00 o o o 00 a 40 9 0r 0404 0 o, a 1610 o 1I 13polybutadiene glycols crosslinked together. According to the present invention, such by-products may be either removed so that refined block ;ler is used or allowed to remain so that use is mad e mixture as a whole. The refined block copolymer h polyester segments on the average connected throu h ne bonds per polybutadiene segment and the ratio of polyester scgmcnts was Test No.1 Use was made of 33% styrene solutions of the block copolymers obtained in Examples Nos. 1 and 2 to test compatibility and/or dispersibility with the following thermosetting unsaturated polyester resins: Yupika 7507 (produced by Nippon, Yupika, Inc.), Polyset 9120, Polyset 9107, Polyset 2212 and Polyset 6200 (the last four produced by Hitachi Kasei, Inc.). Phase separation of about 10% was observed in 24 hours only in the combination of the block copolymer of Example No.2 and Polyset 9107. With the other combinations, no phase separation was observed even without a thickener.

Accordingly, it was anticipated that molded products with uniform surface lustre would be obtainable by many molding methods if aforementioned combinations were used. Thus, for each of the two kinds of block polymers, a liquid with 40 parts of 33% styrene solution, 60 parts of Yupika 7507, 1.5 parts of tertiary butyl perbenzoate and 3.0 parts of zinc stearate was prepared inside a Banbury mixer into which 200 parts of calcium carbonate powder were added and after the mixture became uniform, 60 parts of glass fibers of h inch in length were added. One minute later, the mixer was stopped and a premix was obtained. These premixes are based on the compositions of the present invention. Products formed therefrom at mold temperature of 145 were found to have uniform surface lustre. The molding shrinkage was 0.004% when use was made of the block copolymer of Example No.1 and 0.005% with the block copolymer of Example No.2. The Izod impact strength was 17.0 ft-lb/inch when use was made of the block copolymer of Example No.1 and 17.4 ft-

TR'\

r %07j13,c sspe.001,hardresi.spe,13 14' 0 14lb/inch with the block copolymer of Example No.2.

The premixture which is obtainable in the same way as described above except alpha, omega-1, 2-polybutadiene glycol (described in Example No.1) is substituted for the block copolymer is a known composition but the surface of its molded products was full of spots and cosmetically much inferior. Its Izod impact strength was 11.8 ft-lb/inch.

Testi.No A 33% styrene solution of the block copolymer obtained in Example No.3 was prepared. Uniformly mixed with 40 parts of this solution were 60 parts of Polyset 9120, 3 parts of zinc stearate, 1.5 prts of tertiary butyl perbenzoate, 140 parts of calcium carbonate powder and 0.3 parts of parabenzoquinone, and 2 parts of magnesium oxide was subsequently added to immediately produce a composition for SMC containing glass fibers of 1 inch in length. This composition which embodies the present invention was used to produce molded products with mold temperature of 1400C. Although some cloudiness was observed on the surface, the surface lustre was generally uniform and the molding shrinkage was 0.06%.

For comparison, use was made of a known composition for SMC obtained by the same method as described above except the block copolymer was substituted by alpha, omega-1, 2-polybutadiene glycol (described in Example No.l). The surface of its molded products was full of lustre spots and running designs were also observable. The molding shrinkage was In this situation, the dope stability was poor before the addition of magnesium oxide and phase separation was clearly observable. In this respect, too, it was clear that its industrial application is extremely difficult.

900713,csspe.001,hardresLspe,14 i*a--u1cucj.Lf uacltUL-clLeu roiyesr-er tKesin Uompositions The following statement is a full description of this invention, including the best method of performing it know to us:m.inum~ t Test No.3 Aft ft a a a §as a a Oftft a b a a..

a a ~ft 0 a 0 0~0 a Added into 500 parts each of 33% styrene solutions of the two block copolymers obtained in Examples Nos. 1 and 2 were 500 parts of Polylight PC- 670 (produced by Dai Nippon Ink, Inc.) as thermosetting unsaturated polyester resin. Into this were dissolved 60 parts of cobalt naphthenate to obtain a liquid with viscosity of 830 centipoise. As this liquid was directed into a resin injection mold (called RIM or RTM) with a glass mat, acetyl aceton peroxide was introduced into the mold by a pump such that its ratio in the mixture would be The liquid inlet of the mold had a diameter of 20mm and the mold temperature at the time was 25 oC. The mold temperature began to rise two hours later because of the heat of polymerization and a maximum temperature of 70oC was reached three hours later. The mold was opened three hourn; still later to take out the product. The product had a uniform exterior and there were no lustre spots. The surface was much smoother than that of a comparison product obtained in the same manner as described above except the block copolymer was not used. No glass fibers were observable from outside.

The block copolymer obtained in Example No.4 was directly use thout refinement to prepare a 33% styrene solution. A unifo r-ixture was made of 40 parts of this solution, 60 parts of Polyset 91 produced by Hitachi Kasei, Inc.) as thermosetting unsaturated eoyster resin and 1.5 parts of tertiary butyl perbenzoate. Into thi ere further added 140 parts of calcium carbonate powder and 5 par f MDI were added to this dope while stirring to produce a composii n for SMC having 27% of glass fibers of 1 inch in length. This position embodies the present invention and it was formed into aeet at 145oC. Because the MDI method of thickening was used, the urface of the molded product was yellowish brown but the lustre spots were a a o a aaa o 8~ a 04 a a o ~aa aft b~ a a a a m iiiiin.. i iil itn h ii -g shitm a ¢ige i 7 Ii., i'Q.VU iiiirt'ii ti 900713,csspe.001,hardresLspe,15 ii 1.

-16- 16.5 ft Ibinch.

By contract, the surface of a comparison product obtained b same method as described above except the block copolymer of present invention was substituted by unsaturated polyesterw i'grafted polystyrene (described in Example No.1 of Japanese ent Publication Tokkai 60-99158) was less strongly colo ut there were lustre spots and glass fibers to be observed.

Tisuggests that its molding shrinkage was large. Its Izod impact strength (with notch) was 12.0 ft-lb/inch.

Production: Example 0 00 Placed inside an autoclave were 52.3g (0.35 moles) of phthalic anhydride, 82.5g (0.825 moles) of succinic anhydride, 0.7g of lithium chloride as catalyst and o. 700g (0.5 moles) of hydrogenated alpha, omega-1, 2-polybutadiene glycol 0 G 0 0 o, (Nisso PB-GI1000 with average molecular weight of 1400 and iodine value of 0 6, produced by Nippon Soda, Inc.) and after nitrogen gas was introduced into the reacting system, the mixture was heated to 1300C with stirring. Next, 42.7g (0.74 moles) of propyene oxide was introduced over a period of one hour.

0000 After two hours of aging at 130oC, the reaction was completed to obtain 875g of a yellowish transparent viscous liquid product. The molecular weight of the hydrogenated polybutadiene-polyester block copolymer thus obtained was 1755.

The ratio of polyester segments was 20.2 weight its acid value was 28 and its hydroxyl value was 39.

Production: Example No.6 Placed inside a flask were 786g (0.448 moles) of the block copolymer obtained in Example No.5 and 54.2g (0.54 moles) of succinic anhydride for a reaction at 120-1250C in a nitrogen gas flow for a period of two hours. After the contents were cooled to 500C, 210g of styrene monomer was added to prepare a styrene solution containing 80 weight of block copolnyer. The acid value of 900713,csspe.001,hardresLspe,16 -17this styrene solution containing block copolymer was 51.5 and its hydroxyl value was 0.8. Hydrogenated polybutadiene-polyester block copolymer with carboxyl modified ends of polyester blocks was thus obtained.

Production: Example No.7 Placed inside an autoclave were 166.5g (1.67 moles) of succinic anhydride, 105.2g (0.71 moles) of phthalic anhydride, 1400g (1 mole) of hydrogenated alpha, omega-1, 2-polybutadiene glycol (as used in Example No.5) and 0.6g of lithium chloride and after nitrogen gas was introduced into the system, the mixture was heated to 1300C with stirring. Next, 86.3g (1.49 moles) of propylene oxide was introduced in over a period of 40 minutes at 125-130oC.

After two hours of aging at this temperature, the reaction was terminated to o obtain hydrated polybutadiene-polyester block copolymer. After this was 0 a cooled, it was dissolved and diluted by adding 439g of styrene monomer and a oo styrene solution containing 80 weig;ht of the aforementioned styrene solution i t was obtained. '"The molecular weight of the hydrogenated polybutadienepolyester block copolymer thus obtained is 1758. The ratio of polyester blocks was 20.4%. The acid value of its styrene solution was 26.0 and its hydroxyl value was 26.7.

Production: Example No.8, A mixture of 98g (1 mole) of maleic anhydride, 148g (1 mole) thalic anhydride and 159.6g (2.1 moles) of propylene glycol eated to 215oC in a gas of nitrogen flow for a reaction and the co ensation reaction was stopped when the acid value of the reacting em became 60 to obtain unsaturated polyester. The numerical e age molecular weight of this unsaturated polyester was 754 its hydroxyl value was 89.3.

ixture of 151g (0.2 moles) of the unsaturated polyester thus obtained and 300g (0-mele- hydge ted-ap ega-, 2-polybutadiene glycol (Nisso s Z 0713,csspe.001,hard)esi.spe,17 X is polybutadiene block or hydrogenated polybutadiene block, Y is polyester block having connected by ester linkage one or more Vuz. rr 920702,EEDAT.035,A:\59012TAK.RES,4 -18- PD G13000 series with numerical average molecular weight of 3000 and iodie value of 10, produced by Nippon Soda, Inc.) was dissolved in 1000ml of toluene. Next, 50g (0.2 moles of methylene-di (4-phenyl isocyanate) was ded for a reaction at 500C for one hour with stirring. Toluene was dis i ed away from the reacting system to obtain a yellow viscous liquid product.

What was thus obtained was mainly a block co pler with the hydroxyl groups in unsaturated polyester and hydrognated alpha, omega-1, 2polybutadiene glycol crosslinked to ger by methylene-di(4-phenyl isocyanate).

Also included in part as by-pr uct were compositions with unsaturated polyesters or hydrated ybutadiene glycols crosslinked together. According to the present inv tion, such by-products may be either removed so that Srefined blo copolymer is used or allowed to remain so that use is made of the iure as a whole. The refined block copolymer had two polyester egments on the average connected through urethane bonds per hydrated ne-ef polyester segments was Text Use was made of 33% styrene solutions of the block copolymers obtained in Examples Nos.5 and 6 to test compatibility and/or dispersibility with the following thermosetting unsaturated polyester resins: Yupika 7507 (produced by Nippoti Yupika, Inc.), Polyset 9120, Polyset 9107, Polyset 2212 and Polyset 6200 (the last four produced by Hitachi Kasei, Inc.). Phase separation of about 10% was observed in 24 hours only in the combination of the block copolymer of Example No.6 and Polyset 8107. With the other combinations, no phase separation was observed even without a thickener.

Accordingly, it was anticipated that molded products with uniform surface lustre would be obtainable by many molding methods if aforementioned combinations were used. Thus, for each of the two kinds of block polymers, a liquid with 40 parts of 33% styrene solution, 60 parts of Yupika 7507, 1.5 parts 900713,c-sspe.001,hardresLspe,18 end of a chain. They may be connected to a chain either directly or indirectly through any groups of atoms. As for the liquid rubber compounds which form 4 0713,c sspe.001,hardresLspe,5 j m 4 -19 of tertiary butyl perbenzoate and 3.0 parts of zinc stearate was prepared inside a Banbury mixer into which 200 parts of calcium carbonate powder were added and after the mixture became uniform, 60 parts of glass fibers of h inch in length were added. One minute later, the mixer was stopped and a premix was obtained. These premixes are based on the compositions of the present invention. Products formed therefrom at mold temperature of 1400C were found to have uniform surface lustre. The molding shrinkage was less than 0.004% when use was made of the block copolymer of Example No.5 and less than 0.005% with the block copolymer of Example No.6.

The premixture which is obtainable in the same way as described above except hydrogenated ilpha, omega-1, 2-polybutadiene glycol (described in Example S" No.l) is substituted for the block copolymer is a known composition but the

S

t surface of its molded products was full of spots and cosmetically much inferior.

o no Test No.6 A 33% styrene solution of the block copolymer obtained in Example No.7 was prepared. Uniformly mixed with 40 parts of this solution were 60 parts of Polyset 9120, 3 parts of zinc stearate, 1.5 parts of tertiary butyl perbenzoate, 140 parts of calcium carbonate powder and 0.3 parts of parabenzoquinone, and 2 parts of magnesium oxide was subsequently added to immediately produce 'f an SMC containing glass fibers of 1 inch in length. This composition which embodies the present invention was used to produce molded products with mold temperature of 1400C. Although some cloudiness was observed on the surface, the surface lustre was generally uniform and the molding shrinkage was 0.05%.

For comparison, use was made of an SMC obtained by the same method as described above except the block copolymer was substituted by hydrogenated alpha, omega-1, 2-polybutadiene glycol (described in Example No.5). The surface of its molded product was full of lustre spots and running designs were 900713,c-sspe.001,hardresispe,19 cyclohexane dicarboxylic anhydrides, cyclohexene dicarboxylic anhydride and end methylene cyclohexene dicarboxylic anhydrides. Examples of 1, 2-epoxides 0 Z O713,c_sspe.01,hardresspe,6 20 also observable. The molding shrinkage was In this situation, the dope stability was poor before the addition of magnesium oxide and phase separation was clearly observable. In this respect, too, it was clear that its industrial application is extremely difficult.

Test No.7 Added into 500 parts each of 33% styrene solutions of the two block copolymers obtained in Examples Nos.5 and 6 were 500 parts of Polylight PC- 670 (produced by Dai Nippon Ink, Inc.) as thermosetting unsaturated polyester resin. Into this were dissolved 60 parts of cobalt naphthenate to obtain a liquid with viscosity of 830 centipoise. As this liquid was directed into a resin a a injection mold (called RIM or RTM) with a glass mat, acetyl aceton peroxide was introduced into the mold by a pump such that its ratio in the mixture would be The liquid inlet of the mold had a diameter of 20mm and the mold temperature at the time was 25oC. The mold temperature began to rise two hours later because of the heat of polymerization and a maximum temperature of 700C was reached three hours still later. The mold was opened still three hours later to take out the product. The product had a 7uniform exterior and there were no lustre spots. The surface was much 4 esmoother that of a comparison product obtained in the same manner as described above except the block copolymer was not used. No glass fibers were observable from outside.

Test No.8 refinement to prepare a 33% styrene soluti t niform mixture was made of 40 parts of this solu l of Poluyset 9127 (produced by Hitachi Kasei, Inc.) as th setting unsaturated polyestepr resin and 1.5 parts of terti utyl perbenzoate. Into this were further added 140 part of calcium temperature powder C was r eached thre e dhoursded till later.is dThe thmold st t 4because they are compatible and dispersible with relatively many kinds of thermosetting unsaturated polyester resins. In some situations, it is effective to 900713,c_sspe.001,hardresLspe,7 I. II- -21- The results of these tests clearly indicate that the compositions according to the present invention provide sufficient compatibility and/or dispersibility as well as excellent workability, and are capable of improving the physical characteristics of molded products such as the surface characteristics and molding shrinkage.

0 0 0 0 0 004 PO 0 o* 0 Sa& o a o f 0 4 It 9 *t S c- A 1900713,csspe.0o1,hardresi.spe,26 f'ro

Claims (2)

1. 22- THE CLAIMS DEFINING THE INVENTION ARE AS FOLLOWS:- 1. A hardenable unsaturated polyester resin composition comprising a block copolymer having one or more polyester blocks formed by starting with carboxyl group or hydroxyl group in liquid rubber compound and by alternate condensation thereof with organic dicarboxylic anhydride and 1,2-epoxide in the presence of a catalyst and liquid rubber compound part formed from monomers selected from the group consisting of butadiene, isoprene, chloroprene and 1,3-pentadiene as constituent segments thereof, and unsaturated polyester. 2. A composition according to claim 1 for use as a sheet molding compound or bulk molding compound further comprising polymerizable monomer, a filler, a curing catalyst, a mold release agent and reinforcing fibers. 3. A composition according to claim 2 further comprising a thickener. S4. A composition according to any one of claims 1 to 3 wherein said liquid 20 rubber compound block is a polybutadiene-type compound block or a partially or completely hydrogenated polybutadiene-type compound block. r 5. A composition according to any one of claims 1 to 3 wherein said liquid rubber compound block includes a polyisoprene-type compound block or a partially or completely hydrogenated polyisoprene-type compound block. 6. A composition according to any one of claims 1 to 5 wherein said organic dicarboxylic anhydride includes one or more anhydrides selected from the group consisting of phthalic anhydride, succinic anhydride, cyclohexane dicarboxylic anhydride, cyclohexene dicarboxylic anhydride and end methylene cyclohexane dicarboxylic anhydride. 920702,EEDAT.035,A:\59012TAKRES,22 14 rmV -23- 7. A composition according to any one of claims 1 to 6 wherein said 1,2-epoxide includes one or more selected from the group consisting of ethylene oxide, propylene oxide and butylene oxide. 8. A composition according to any one of claims 1 to 7 wherein said polyester block is 10-60 weight percentage of said block copolymer. 9. A composition according to any one of claims 1 to 8 wherein said unsaturated polyester includes one or more selected from the group consisting of alpha, beta-ethylenically unsaturated polyester, novolac-type unsaturated polyester and vinyl ester-type unsaturated polyester. A composition as claimed in any one of claims 1 to 9, wherein said block copolymer is of the form X where X is polybutadiene block or hydrogenated polybutadiene block, Y is polyester block having connected by ester linkage one or more types of organic dicarboxylic anhydride selected from the group consisting of phthalic anhydride, succinic anhydride, cyclohexane dicarboxylic anhydride, S2 cyclohexene dicarboxylic anhydride and methylene cyclohexane dicarboxylic 20 anhydride and one or more types of 1,2-epoxide selected from the group o consisting of ethylene oxide, propylene oxide and butylene oxide, n is an integer equal to or greater than 1, and X-fY)n is formed by starting with carboxyl group or hydroxyl group in polybutadiene or "hydrogenated polybutadiene and by alternate condensation of said organic 25 dicarboxylic anhydride and said 1,2-epoxide therewith in the presence of a catalyst. t 11. A composition according to claim 10 wherein said polyester block has terminal carboxylic acid group formed by the reaction of succinic and/or phthalic anhydride with a terminal hydroxyl group of said polyester block. 12. A composition according to claim 10 or claim 11 wherein said 920702,EEDAT.035,AA\59012TAKRES,23 rlaccu nslue an autoclave were ioo.3g 1.o/ moles) or succinic annyarice,
2. 105.2g (0.71 moles) of phthalic anhydride, 1430g (1 mole) of alpha, omega-1, 2-polybutadiene glycol (as used in Example No.l) and 0.6g of lithium chloride. 900713,c_sspe.001,hardresLspe,11 ll- *aurrtr *A 24 unsaturated polyester includes one or more selected from the group consisting of alpha, beta-ethylenically unsaturated polyester. 13. A method of producing a hardenable unsaturated polyester resin composition comprising the steps of forming a block copolymer having both polyester block and liquid rubber compound block and mixing said block copolymer with an unsaturated polyester wherein said block copolymer of the form X- -Y)n where X is polybutadiene block or hydrogenated polybutadiene block, Y is polyester block having connected by ester linkage one or more types of organic dicarboxylic anhydride selected from the group consisting of phthalic anhydride, succinic anhydride, cyclohexane dicarboxylic anhydride, cyclohexene dicarboxylic anhydride and methylene cyclohexane dicarboxylic anhydride and one or more types of 1,2-epoxide selected from the group consisting of ethylene oxide, propylene oxide and butylene oxide, n is an integer equal to or greater than 1, and X-fY)n is formed by starting with carboxyl group or hydroxyl group in polybutadiene or hydrogenated polybutadiene and by alternate condensation of said organic dicarboxylic anhydride and said 1,2-epoxide therewith in the presence of a catalyst. a0 ao 14. A method according to claim 13 further comprising the step of adding vinyl monomers, a filler, a mold release agent and reinforcing fibers. 0 Qo a 15. A method according to claim 13 or claim 14 further comprising the step of adding a thickener. 16. A method according to any one of claims 13 to 15, wherein said block i a copolymer contained 10-60 wt% of said polyester block. 17. A method according to any one of claims 13 to 16, wherein said polyester block has terminal carboxylic acid group formed by the reaction of 920702,EEDAT.035,A:\59012TAK.RES,24 2^M7 I ~rur~ t j 25 succinic and/or phthalic anhydride with a terminal hydroxyl group of said polyester block. 18. A method according to any ine of claims 13 to 17, wherein said unsaturated polyester includes one or more selected from the group consisting of alpha, beta-ethylenically unsaturated polyester. 19. A hardenable unsaturated polyester resin composition as claimed in claim 1 substantially as hereinbefore described with reference to the Examples. 0 A method as claimed in claim 13 substantially as hereinbefore described with reference to the Examples. o f 0 0 000*00 0 00 0 Q oar 0 00 :o 0 0 0 00 o o o e OE oD o or 0 04f 0 eo a i o a 0 o Ur~ e 04 DATED this 2nd day of July, 1992. TAKEMOTO YUSHI KABUSHIKI KAISHA By Its Patent Attorneys DAVIES COLLISON CAVE 920702,EEDAT.35,A:\59I 2TAKRES,25 i