JPH0721101B2 - Thermoplastic resin composition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application] The present invention relates to a polyester-based thermoplastic resin composition,
More specifically, it relates to a polyester-based thermoplastic resin composition having excellent dimensional stability.

[Conventional technology]

A polyester-based resin, for example, an aromatic polyester resin such as polyethylene terephthalate or polybutylene terephthalate has excellent moldability and mechanical properties. Further, the polyether ester block copolymer exhibits various excellent properties such as heat resistance, cold resistance, toughness, chemical resistance, water resistance and oil resistance, and therefore its application as an engineering plastic is expanding.

However, since the polyester-based resin is crystalline, it is easily crystallized when it is melted by heating and then rapidly or gradually cooled when it is molded using a mold or is treated at a high temperature. When crystallizing, the flow direction, flow length, thickness, flow rate, etc. of the polyester resin are often different, and as a result, the speed of shrinkage due to crystallization of each part is different. Deformation such as "," twist, "blister" or "depression" occurs. The deformation of the polyester resin is
This is particularly remarkable in the polyester resin filled with glass fiber.

In order to improve the dimensional stability of the polyester-based resin as described above, a blend with an ABS resin, an aromatic vinyl-based copolymer such as polystyrene, has been proposed (for example, JP-A-56-161455).

However, the methods proposed so far have not yielded sufficiently satisfactory molded articles in terms of total balance of compatibility, physical properties, fluidity and the like. For example, ABS
A mere blend of resin and polyester has poor compatibility and cannot obtain mechanical properties, particularly sufficient weld strength.

[Problems to be Solved by the Invention]

It is an object of the present invention to provide a polyester-based thermoplastic resin composition having improved weld strength by improving the compatibility between the polyester-based resin and the aromatic vinyl-based resin and improving the dimensional stability. To do.

[Means for Solving the Problems]

The present invention relates to (a) a polyester resin: 100 parts by weight, and (b) an aromatic vinyl polymer having a reactive group: 5 to
An aromatic polycarbonate resin having a ratio of 50 parts by weight, (c) a phenolic end group represented by the following formula (I) and a non-phenolic end group represented by the following formula (II) is 1/19 or more. : 5 to 50 W% is blended with the thermoplastic resin composition.

(Here, R ₁ and R ₂ may be the same or different from each other, and each is a hydrogen atom or an alkyl group having 20 or less carbon atoms, which may be halogen-substituted).

As the polyester resin as the component (a) in the present invention, known resins can be used. In particular, aromatic polyester resins and polyetherester block copolymers can be used.

The aromatic polyester resin is a polyester having an aromatic ring in a polymer chain unit, and is an aromatic dicarboxylic acid and a diol (or an ester-forming derivative thereof).
It is a polycondensate or copolymer containing and as main components.

Here, as the aromatic dicarboxylic acid, terephthalic acid,
Isophthalic acid, orthophthalic acid, 1,5-naphthalenedicarboxylic acid, naphthalene-2,5-dicarboxylic acid, naphthalene-
2,6-dicarboxylic acid, biphenyl-3,3'-dicarboxylic acid, biphenyl-4,4'-dicarboxylic acid, diphenyl ether-4,4'-dicarboxylic acid, diphenylmethane-4,
4'-dicarboxylic acid, diphenylsulfone-4,4'-dicarboxylic acid, diphenylisopropylidene-4,4'-dicarboxylic acid, 1,2-bis (phenoxy) ethane-4,4'-
Dicarboxylic acid, anthracene-2,5-dicarboxylic acid, p-
Terphenylene-4,4'-dicarboxylic acid, pyridine-2,5
-Dicarboxylic acid and the like can be mentioned, and among them, terephthalic acid can be preferably used.

You may use these aromatic dicarboxylic acid in mixture of 2 or more types. If the amount is small, one or more of these aromatic dicarboxylic acids and one or more adipic acid, azelaic acid, dodecanedioic acid, sebacic acid, or other alicyclic dicarboxylic acid such as cyclohexanedicarboxylic acid may be mixed. Can be used. As the diol component, ethylene glycol, propylene glycol, butylene glycol, hexylene glycol, neopentyl glycol, 2-methylpropane-1,3-diol, dietrene glycol, triethylene glycol,
And the like, alicyclic diols such as cyclohexane-1,4-dimethanol, and the like, and mixtures thereof. If the amount is small, the molecular weight is 400 to 6,0.
One or more kinds of 00 long chain diols, that is, polyethylene glycol, poly-1,3-propylene glycol, polytetramethylene glycol and the like may be copolymerized. Specific aromatic polyester resins include polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polyethylene naphthalate, polybutylene naphthalate, polyethylene-1,2-bis (phenoxy) ethane-4,4'-diene. Examples thereof include carboxylate and polycyclohexanedimethanol terephthalate. Further, copolymerized polyesters such as polyethylene isophthalate / terephthalate, polybutylene terephthalate / isophthalate, polybutylene terephthalate / decane dicarxylate, etc. can also be used. Of these, polyethylene terephthalate and polybutylene terephthalate are preferable, and polybutylene terephthalate is particularly preferable.

Further, as the above polyether ester block copolymer (polyester elastomer), there is disclosed in JP-A-52-50
Known materials described in Japanese Patent No. 347 can be used. This polyetherester block copolymer is composed of (a) dicarboxylic acid component, (b) low molecular weight glycol component, and (c) polyoxyalkylene glycol component.

As the dicarboxylic acid used as (a) above, aromatic dicarboxylic acids are preferable. Particularly preferred aromatic dicarboxylic acid, terephthalic acid, isophthalic acid, naphthalene-1,5-dicarboxylic acid, naphthalene-2,6-dicarboxylic acid, naphthalene-2,7-dicarboxylic acid, bisphenyl-4,
4'-dicarboxylic acid, diphenylsulfone-4,4'-dicarboxylic acid, phenoxyethane-4,4'-dicarboxylic acid and the like can be mentioned. It is also possible to use aliphatic and cycloaliphatic dicarboxylic acids and their mixtures.

Examples of the low molecular weight glycol used as the above (b) include aliphatic glycols such as ethylene glycol, trimethylene glycol, tetramethylene glycol, and hexamethylene glycol, 4,4'-bis-β-hydroxyethoxybisphenol A, 4,4 ' Mention may be made of glycols having an aromatic group such as'-bis-β-hydroxyethoxydiphenyl sulfone and glycols having an alicyclic group such as cyclohexanedimethanol. Among these, preferred glycols include aliphatic glycols.

The above-mentioned component (c) is preferably an average molecular weight of 500 to
5,000 polyoxyalkylene glycols are used,
Examples thereof include polyoxyethylene glycol, polyoxypropylene glycol, polyoxytetramethylene glycol, polyoxypentamethylene glycol, polyoxyhexamethylene glycol and the like, or copolymers thereof.

Further, the polyether ester block copolymer used in the present invention includes known polyether imide ester block copolymers disclosed in JP-A-62-501365. Specific examples of preferred polyetherimide ester block copolymers include poly (propylene ether) diamine, butanediol dimethyl terephthalate, and copolymers produced from trimellitic anhydride using a titanate ester catalyst. .

The aromatic polyester resin and the polyether ester block copolymer may be contained in the resin composition of the present invention at a composition ratio (aromatic polyester resin / polyether ester block copolymer) of 9 to 0.1. desirable.

Next, the component (b), which is a characteristic part of the present invention, is an aromatic vinyl polymer containing an oxazonyl group or an epoxy group. Such a polymer can be obtained, for example, by copolymerizing (i) an oxazonyl group-containing unsaturated monomer or an epoxy group-containing unsaturated monomer and (ii) an aromatic vinyl compound.

The preferred oxazonyl group-containing unsaturated monomer (i) has the general formula: Where Z is a compound containing a polymerizable double bond. The preferred substituent Z is as follows.

In these formulas, R is a hydrogen atom or an alkyl group or an alkoxy group having 1 to 6 carbon atoms, for example, a methyl group, i- and n-propyl groups or a butyl group.

Particularly preferred compounds have the general formula: In the vinyl oxazoline represented by, R has the above-mentioned meaning and is preferably a hydrogen atom or a methyl group.
Further, as a preferable epoxy group-containing unsaturated monomer,
Glycidyl methacrylate, glycidyl acrylate,
Examples thereof include vinyl glycidyl ether, hydroxyalkyl (meth) acrylate glycidyl ether, polyalkylene glycol (meth) acrylate glycidyl ether, and glycidyl itaconate.

Further, as the aromatic vinyl compound (ii), styrene,
-Α-methylstyrene, p-methylstyrene, pt-butylstyrene and the like can be mentioned, and styrene and α-methylstyrene are particularly preferable.

The copolymerization amount of the (i) oxazonyl group-containing unsaturated monomer or the epoxy group-containing unsaturated monomer in the above copolymer is preferably 0.001 to 14% by weight, more preferably 0.01 to 5% by weight. It is a range. If the copolymerization amount is less than 0.001% by weight, the impact strength of the composition will be low, and if it exceeds 14% by weight, the copolymer will be easily gelated, and a molded product with a good surface condition will be obtained. I can't get it.

The polymer of the component (b) may further contain a vinyl cyanide monomer component such as acrylonitrile as a copolymerization component.

Further, with respect to 100 parts by weight of the total of the above-mentioned copolymerization components,
It is also possible to copolymerize 0 to 70 parts by weight of another copolymerizable monomer. Other copolymerizable monomers include methyl methacrylate, ethyl methacrylate, methacrylic acid-
Examples thereof include α, β-unsaturated carboxylic acid esters such as t-butyl and cyclohexyl methacrylate.

The polymer of the component (b) is, for example, an oxazolinyl group-containing or epoxy group-containing acrylonitrile-styrene copolymer, an oxazolinyl group-containing or epoxy group-containing AB.
It includes S resin (butadiene), oxazonyl-containing or epoxy group-containing graft copolymer in which acrylonitrile, oxazoline or epoxy and polystyrene are grafted to butadiene.

The method for producing the copolymer of the component (b) is not particularly limited, and bulk polymerization, solution polymerization, bulk-suspension polymerization, suspension polymerization,
A commonly known method such as emulsion polymerization is used. The method of charging the copolymerization components is not particularly limited, and may be collectively charged at the beginning, and in order to prevent uneven distribution of the composition distribution of the copolymer, that is, uneven distribution of the components due to the difference in the polymerization rate. Polymerization may be carried out while a part or all of the charged monomers are continuously charged or dividedly charged.

In the resin composition of the present invention, in addition to the components (a), (b) and (c) described above, an optional component (d) an aromatic or aliphatic vinyl copolymer and (e) an inorganic component. Fillers can also be added.

The aromatic or aliphatic vinyl-based copolymer is not particularly limited and may contain an aromatic or aliphatic vinyl monomer component, and may be a homopolymer or a copolymer. Aromatic vinyl polymers or copolymers are preferred. A preferred specific example is polystyrene (P
S), styrene / acrylonitrile copolymer (SAN), polymethylmethacrylate (PMMA), styrene / methylmethacrylate / acrylonitrile copolymer, α-methylstyrene / acrylonitrile copolymer, α-methylstyrene / styrene / acrylonitrile Vinyl-based polymers such as copolymers, α-methylstyrene / methyl methacrylate / acrylonitrile copolymers, p-methylstyrene / acrylonitrile copolymers, styrene / n-phenylmaleimide copolymers; methacrylic acid-butadiene-styrene. Examples include terpolymer (MBS) resin; ABS resin, AES resin; AAS resin; These may be used alone or in combination of two or more.

The aromatic or aliphatic vinyl polymer as the optional component (d) can be blended in an amount of 0 to 100 parts by weight, preferably 0 to 50 parts by weight, based on 100 parts by weight of the component (a).

Examples of the inorganic filler as the optional component (e) include glass fiber, glass flake, metal fiber, metal flake, carbon fiber, mica, clay and the like, which can be used as they are. This component (e) is the component (a)
0 to 85 parts by weight can be added to 100 parts by weight.

Further, depending on the purpose, pigments, dyes, heat stabilizers, antioxidants, ultraviolet absorbers, light stabilizers, lubricants, plasticizers, antistatic agents, flame retardants and the like can be added as appropriate.

As the polycarbonate resin of the component (c) in the present invention, the following aromatic polycarbonates can be used to obtain particularly preferable results.

That is, an aromatic polycarbonate having a ratio of the phenolic end group represented by the following formula (I) to the non-phenolic end group represented by the following formula (II) is 1/19, (R ₁ and R ₂ can be the same or different from each other and are each a hydrogen atom or an alkyl group having up to 20 carbon atoms and are optionally halogen substituted).

The terminal group ratio of the aromatic polycarbonate can be easily adjusted by preparing the aromatic polycarbonate by a transesterification method and changing the molar ratio of diphenyl carbonate as a raw material and diphenol (for example, bisphenol A) at that time. In the present invention, the aromatic polycarbonate has the formula (Each R is phenylene, halogen-substituted phenylene or C ₁
To C ₂₀ alkyl-substituted phenylene, and A and B mainly have a repeating unit represented by a hydrogen atom, a C ₁ -C ₁₂ hydrocarbon containing no aliphatic unsaturation or a cycloalkane group together with an adjacent carbon atom). . For example, when bisphenol A and diphenyl carbonate are transesterified, the terminal of the polycarbonate is a phenolic residue derived from bisphenol A or a phenyl group derived from diphenyl carbonate. Therefore, when the molar ratio of bisphenol A is increased during the transesterification reaction, the ratio of phenolic end groups in the produced polycarbonate increases. The aromatic polycarbonate may be branched. Such branched polycarbonates are obtained as branched thermoplastic random branched polycarbonates by reacting polyfunctional aromatic compounds with diphenol and / or carbonate precursors.

In the aromatic polycarbonates generally used in the past, particularly aromatic polycarbonate produced by the phosgene method, the ratio of the phenolic end groups to the non-phenolic end groups is 1/20 or less. That is, bisphenol A
Polycarbonate is produced by reacting phosgene with phosgene, but the polymer end is blocked with phenol (hydroxyl group reacts) by adding a small amount of phenol in the raw material or during the reaction.

The aromatic polycarbonate in the present invention exerts a great effect when the ratio of the phenolic terminal group is 1/19 or more, preferably 1/10 or more.

The OH group concentration of the phenolic end group is 3600 cm of FTIR.
It is determined by measuring the absorption intensity at ^-1 . The total terminal group concentration is calculated by determining the average molecular weight based on the IV (intrinsic viscosity) value measured with a methylene chloride solution. The Shnell equation was used when converting the IV value to the average molecular weight.

IV = 1.23 × 10 ⁻⁴ M ^0.23 where M is the viscosity average molecular weight The method for producing the thermoplastic resin composition according to the present invention is not particularly limited, and ordinary methods can be satisfactorily used. However, melt blending is generally preferred. Any melt-mixing method is applicable provided that it can process the molten viscous mass. The method is used in batch or continuous mode. In particular, an extruder, a Banbury mixer, a kneader, a roller and the like can be mentioned as examples.

〔Example〕

Hereinafter, the present invention will be described in more detail with reference to Examples.
The present invention is not limited to these. The following compounds were used in the examples.

Component (a) PBT ... Polybutylene terephthalate, trademark; Valox, manufactured by General Electric Co. Component (b) r-PS ... Polystyrene containing 5 wt% of oxazoline component, trademark; CX-RPS 1005, Nippon Shokubai Kagaku Kogyo ( Co., Ltd. r-AS · · vinyl oxazoline 5% by weight, styrene 70% by weight and acrylonitrile 25% by weight, a copolymer having a number average molecular weight of about 50,000, trademark: CX-RAS1005, a component manufactured by Nippon Shokubai Kagaku Kogyo Co., Ltd. (C) Polycarbonate obtained by polymerizing PC-A ... Bisphenol A by the phosgene method and end-capping with phenyl groups so that the ratio of phenolic end groups is 1/99 (Lexan; trademark, manufactured by General Electric Co., methylene chloride). Intrinsic viscosity at 25 ° C
0.50de / g) PC-B ··· obtained by transesterification of diphenyl carbonate and bisphenol A. (In methylene chloride
Intrinsic viscosity measured at 25 ° C is 0.50 de / g, and the ratio of phenolic end groups to non-phenolic end groups is about 1/1) Other components AS: Acrylonitrile / styrene copolymer, trademark;
Sanrex, Mitsubishi Monsanto Co., Ltd. glass fiber ... Conventional products <Examples 1 to 6 and Comparative Examples 1 to 3> Each component was mixed at a ratio shown in Table 1, and the temperature was 250 ° C. and the mold temperature was 60.
Under a condition of ° C, a double gate and a single gate were used to form a dumbbell for tensile test of ASTM D638. The double gate test piece was used for measuring the weld strength.

Tensile strength was measured according to ASTM D638.

As is clear from Table 1, all of the thermoplastic resin compositions of the present invention have excellent weld strength. On the other hand, in the comparative example containing no PC, it can be understood that the weld strength is significantly impaired.

[Advantages of the Invention] The thermoplastic resin composition according to the present invention has markedly improved weld strength because the compatibility of each component is significantly improved. Therefore, according to the present invention, the dimensional stability of the polyester resin can be improved without impairing the excellent properties inherent in the polyester resin.

Claims (1)

[Claims] 1. (a) Polyester resin: 100 parts by weight, (b) Reactive group-containing aromatic vinyl polymer: 5 to 60 parts by weight (c) Phenolic compound represented by the following formula (I) End groups,
Aromatic polycarbonate resin having a ratio with a non-phenolic terminal group represented by the following formula (II) of 1/19 or more: 5 to 50
And a thermoplastic resin composition. (Here, R ₁ and R ₂ may be the same or different from each other, and each is a hydrogen atom or an alkyl group having 20 or less carbon atoms, which may be halogen-substituted).