Classifications

• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
  • C08G81/00—Macromolecular compounds obtained by interreacting polymers in the absence of monomers, e.g. block polymers
  • C08G81/02—Macromolecular compounds obtained by interreacting polymers in the absence of monomers, e.g. block polymers at least one of the polymers being obtained by reactions involving only carbon-to-carbon unsaturated bonds
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
  • C08G81/00—Macromolecular compounds obtained by interreacting polymers in the absence of monomers, e.g. block polymers
  • C08G81/02—Macromolecular compounds obtained by interreacting polymers in the absence of monomers, e.g. block polymers at least one of the polymers being obtained by reactions involving only carbon-to-carbon unsaturated bonds
  • C08G81/024—Block or graft polymers containing sequences of polymers of C08C or C08F and of polymers of C08G
  • C08G81/027—Block or graft polymers containing sequences of polymers of C08C or C08F and of polymers of C08G containing polyester or polycarbonate sequences

Definitions

• the present invention relates to a process for producing a polyolefin-polyester graft copoly er which is effective as a compatibilizing agent for both of ingredients in a resin composition comprising an engineering plastic such as a polycarbonate and a polyolefin. More in particular, it relates to a method of preventing gel formation upon producing a graft copolymer of a polyester having specific intrinsic viscosity and concentration of terminal carboxyl group and a modified polyolefin containing epoxy or carboxyl groups.
• Aromatic polycarbonates have excellent impact resistance, heat resistance, rigidity and dimensional stability, but they involve a drawback of insufficient solvent resistance and moldability. For obtaining a composition of well-balanced mechanical properties while compensating these drawbacks, various studies have been made on blends with polyolefin. However, since the compatibility between a polyolefin and a polycarbonate is not so good, it has been attempted to add third ingredients for improving the compatibility.
• Japanese Patent Laid Open Sho 57-108151 discloses a butyl rubber
• Japanese Patent Laid Open Sho 57-108152 discloses an ethylene-propylene copolymer and/or ethylene-propylene-diene copolymer
• Japanese Patent Laid Open Sho 57-111351 discloses an isoprene rubber and/or methyl pentene polymer.
• none of the ingredients is sufficient as the compatibilizing agent for the polycarbonate resin and the polyolefin, and not only the impact resistance of the molding product is rapidly reduced but also there is a problem of surface peeling as the amount of the polyolefin is increased.
• the present inventors have previously proposed a process for producing a polyolefin-polyester graft copolymer that can be used as a satisfactory compatibilizing agent for a polycarbonate resin and a polyolefin by reacting from 15 to 85 parts by weight of a polyester having an intrinsic viscosity [ ] of 0.30 and 1.2 and a concentration of terminal carboxyl group of 15 to 200 meq/Kg, and from 85 to 15 parts by weight of a modified polyolefin containing 0.2 to 5 mol 1 of epoxy groups and having a weight average molecular weight of 8,000 to 140,000 in a twin screw extruder at 260 - 320°C (Japanese Patent Application Sho 63-25BB83).
• an object of the present invention to provide a process for stably producing a polyolefin-polyester graft copolymer which is a satisfactory compatibilizing agent for an engineering plastic such as a polycarbonate resin and a polyolefin, without clogging the extruder while preventing gel formation.
• T e present inventors have made earnest studies for attaining the foregoing object and, as a results, have found that it can be attained by the reaction while defining the intrinsic viscosity and the concentration of the terminal carboxyl group of a polyester and the functional group content and the molecular weight of a modified polyolefin to respective predetermined ranges and by adding water to the reaction system thereby accomplishing the present invention.
• a process for producing a polyolefin-polyester graft polymer according to the present invention resides in melt-kneading to react:
• the polyester used in the present invention is, generally, a thermoplastic resin comprising a saturated dicarboxylic acid and a saturated difunctional alcohol and there can be mentioned, for example, polyethylene terephthalate, polypropylene terephthalate, polytetra ethylene terephthalate (polybutylene terephthal te), polyhexa ethylene terephthalate, polycyclohexane-1 ,4-dimethylol terephthalate and polyneopentyl terephthalate.
• polyethylene terephthalate and polybutylene terephthalate are particularly preferred.
• the polyester has an intrinsic viscosity [ ⁇ ] of 0.5 to 1.8 and a concentration of terminal carboxyl group of 10 to 100 meq/Kg.
• the intrinsic viscosity [ ⁇ ] (dl/g) is determined from a solution viscosity measured in an o-chlorophenol solvent at 25°C. If the intrinsic viscosity [ ⁇ ] of the polyester is less than 0.50, the effect for improving the compatibility is insufficient. On the other hand, if it exceeds 1.8, the melt viscosity of the reaction product is increased to bring about a difficulty in fabrication. Meanwhile, if the concentration of the terminal carboxyl group is less than 10 meq/Kg, reactivity with the modified polypropylene is poor. On the other hand, if it exceeds 100 meq/Kg, the reactivity with the modified polypropylene is excessively high tending to form a gel.
• the intrinsic viscosity [ • * ] is from 0.50 to 1.0 and the concentration of the terminal carboxyl group is from 10 to 100 meq/Kg. If the intrinsic viscosity [ ⁇ ] exceeds 1.0, the melt viscosity of the graft polymer is increased to cause gelation.
• ttie tereptittvalic acid ingredient in the polyethylene terephthalate may be substituted with alkyl group, halogen group, etc., and the glycol ingredient may contain, in addition to ethylene glycol, up to about 50% by weight of other glycol, for example, 1,4-butylene glycol, propylene glycol, hexamethylene glycol, etc.
• the intrinsic viscosity i ⁇ ] is from 0.5 to 1.8 and the concentration of the terminal carboxyl group is from 10 to 100 meq/Kg.
• the terephthalic acid ingredient may be substituted with alkyl group, halogen group, etc.
• the glycol ingredient may contain, in addition to 1,4 butylene glycol, up to about 50% by weight of other glycol, for example ethylene glycol, propylene glycol and hexamethylene glycol.
• modified polyolefin used in the present invention is a polyolefin copolymerized with an unsaturated monomer having a functional group.
• the unsaturated monomer having the carboxyl group is an unsaturated carboxylic acid or anhydride thereof and it can include, for example, monocarboxylic acid such as acrylic acid or methacrylic acid, dicarboxylic acid such as maleic acid, humaric acid or itaconic acid, dicarboxylic acid anhydride such as maleic acid anhydride or itaconic acid anhydride, dicarboxylic acid and anhydride thereof being particularly preferred.
• monocarboxylic acid such as acrylic acid or methacrylic acid
• dicarboxylic acid such as maleic acid, humaric acid or itaconic acid
• dicarboxylic acid anhydride such as maleic acid anhydride or itaconic acid anhydride
• dicarboxylic acid and anhydride thereof being particularly preferred.
• the unsaturated monomer having epoxy group there can be mentioned glycidyl ester of metacrylic acid.
• olefins such as ethylene, propylene, butene-1 and pentene-1. These olefins may be used alone or as a mixture of two or more of them. Further, the olefins may be incorporated, as required, with less than 10% by weight of other copoly erizable monomers, for example, vinyl acetate, isoprene, chloroprene and butadiene.
• copolymers of glycidyl acrylate or methacrylate and ethylene are particularly preferred.
• the modified polyolefin containing carboxyl group of epoxy group may be any of block copolymer, graft copolymer, andom copolymer or intercopolymer.
• the weight average molecular weight of the modified polyolefin is from 8,000 to 140,000 and the content of the carboxyl group or epoxy group in the modified polyolefin is from 0.2 to 5 mol %.
• the weight average molecular weight was measured by a gel permeation chromatography (GPC) and converted as the not-modified polyolefin. Further, the carboxyl group content was determined based on the elemental analysis value. The epoxy group content was determined based on the analysis value for elemental oxygen. If the weight average molecular weight is less than 8,000, the effect of improving the compatibility is insufficient. On the other hand, if it exceeds 140,000, the melt viscosity is increased to worsen the moldability.
• the carboxyl group or the epoxy group is less than 0.2 mol %, reactivity with the polyester is poor in which graft copolymer is less formed. On the other hand, if it exceeds 5 mol %, melt viscosity of the reaction product is increased due to excess reaction with the polyester, tending to form gel-like material easily.
• both of them are dry blended and then melt-kneaded at 260 - 320 ⁇ C for 0.5 to 15 in.
• the melt-kneading is preferably conducted in an extruder, particularly, in a twin screw extruder. If the reaction temperature is lower than 260 C C, grafting is to sufficient. On the other hand, if it exceeds 320°C, excess reaction occurs to cause blocking in the extruder due to the gel formation. Also, the resin tends to be degraded easily.
• the blending amount of the polyester and the modified polyolefin is from 10 to 90 parts by weight, preferably, from 20 to 80 parts by weight for the former and from 90 to 10 parts by weight and, preferably, from 80 to 20 parts by weight for the latter. If the polyester is less than 10 parts by weight or greater than 90 parts by weight, the amount of the graft copolymer formed is reduced.
• the polyester and the modified polyolefin are reacted under melt-kneading, wherein from 0.05 to 2.0 parts by weight of water is added based on 100 parts by weight of the sum of the polyester and the modified polyolefin. If the addition amounts of the water is less than 0.05 parts by weight, gel formation can not be prevented sufficiently. If it exceeds 2.0 parts by weight, the molecular weight of the graft copolymer is too low to sufficiently attain the improving effect for the compatibility.
• water is continuously supplied to the inside of the extruder by means of a pump. Particularly, the addition of water to the downstream side of a kneading zone of the extruder is preferred.
• the thus obtained polyolefin-polyester graft copolymer is satisfactory as a compatibilizing agent for a polycarbonate resin and a polyolefin, and, generally, it is added at a ratio of 1 to 30 parts by weight based on 100 parts by weight of the sum for both of them.
• the intrinsic viscosity [ ⁇ ] and the concentration of the terminal carboxyl group of the polyester, and the carboxyl group or epoxy group content and the weight average molecular weight of the modified polyolefin used in the grafting reaction to respective specific ranges, and adding water upon grafting reaction, the grafting reaction can be controlled easily, and gel formation due to excess reaction can be prevented.
• the polyester chain portion in the graft copolymer is hydrolized to reduce the molecular weight.
• grafting ratio is not reduced.
• Intrinsic viscosity [7 : determined from a solution viscosity measured in an o-chlorophenol solvent at 25°C.
• Weight average molecular weight measured by 6PC method and determined as a polyethylene-converted valued.
• MFR determined at 280°C under the load of 2160 g or 216 Kg.
• Grafting rate was determined by isolating ingredients insoluble to both of m-cresol (100 ⁇ C) and xylene (100°C).
• water was added at a ratio shown in Table 1 based on 100 parts by weight of the sum of the polyethylene terethalate and a modified polyethylene to the down- stream side of the kneading zone in a twin screw extruder.
• the residence time in the extruder was about 1 min.
• a copolymer was produced and measured in the same manner as in Example 1 except for using, as a polyester, a mixture of 50% by weight of a polyethylene terephthalate having an intrinsic viscosity i- t m of 0.70 and a concentration of terminal carboxyl group of 35 meq/Kg, and 50% by weight of a polyethylene terephthalate having an intrinsic viscosity i-* ⁇ of 0.73 and a concentration of terminal carboxyl group of 60 meq/Kg.
• the results are also shown in Table 1.
• Copolymers were produced in the same manner as in Example 1 except for changing the ratio (by weight) of the polyethylene terephthalate and the modified polyethylene to 50/50 (in Example 10) and 80/20 (in Example 11). The results are also shown in Table 1.
• polyester having an intrinsic viscosity [ ⁇ & nd a concentration of terminal carboxyl group each within a predetermined range, and a modified polyolefin having carboxylic group and epoxy group contents and melt flow rate (MFR) each in a predetermined range are reacted, and since water is added, it is possible to prevent the gel formation due to excess reaction and prevent resin clogging of the extruder while maintaining satisfactory fluidity without reducing the grafting ratio.
• the 'polyolefin-polyester graft copolymer according to the present invention thus obtained is extremely effective as a compatibilizing agent for an engineering resin such as a polycarbonate resin and a polyolefin.

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• Chemical & Material Sciences (AREA)
• Health & Medical Sciences (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Medicinal Chemistry (AREA)
• Polymers & Plastics (AREA)
• Organic Chemistry (AREA)
• Other Resins Obtained By Reactions Not Involving Carbon-To-Carbon Unsaturated Bonds (AREA)
• Compositions Of Macromolecular Compounds (AREA)
• Polyesters Or Polycarbonates (AREA)

Applications Claiming Priority (4)

Publications (2)

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ID=26439708

Family Applications (1)

Country Status (5)

Citations (3)

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• 1989
  • 1989-12-14 JP JP1324268A patent/JPH0347843A/en active Pending
• 1990
  • 1990-04-11 AU AU54403/90A patent/AU5440390A/en not_active Abandoned
  • 1990-04-11 KR KR1019910701363A patent/KR920701313A/en not_active Withdrawn
  • 1990-04-11 WO PCT/US1990/001970 patent/WO1990012837A1/en not_active Ceased
  • 1990-04-11 EP EP19900906619 patent/EP0469038A4/en not_active Withdrawn

Patent Citations (3)

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