KR20070070686A - Polyester thermoplastic resin composition - Google Patents

Abstract

Provided is a polyester-based thermoplastic resin composition, which has excellent impact resistance, heat resistance, mechanical strength, chemical resistance and blow moldability, and low gloss. The polyester-based thermoplastic resin composition comprises: (A) 10-70 parts by weight of a polyester resin; (B) 10-60 parts by weight of a polycarbonate resin; (C) 5-50 parts by weight of a styrene rubbery copolymer; and (D) 5-20 parts by weight of an ethylene/alkyl (meth)acrylate copolymer. Preferably, the ethylene/alkyl (meth)acrylate copolymer has a melt index of 0.01-40g/10 min. at 190 deg.C under 2.16 kgf.

Description

Polyester Thermoplastic Resin Composition

The present invention relates to a thermoplastic resin composition having excellent mechanical strength, impact resistance and blow moldability, and more particularly, to a polyester resin, a polycarbonate resin, a styrene rubber copolymer, and an ethylene / alkyl (meth) acrylate. It relates to a thermoplastic resin composition.

In general, polyester resins have mechanical strength, electrical properties, and chemical resistance, so are widely used in automobiles, electrical / electronic parts, etc., but the glass transition temperature (Tg) is 40 to 60 ° C., which has low impact resistance at room temperature and low temperature. There is this. Therefore, alloys with rubber have been studied for applications in fields requiring impact resistance.

U.S. Patent Nos. 4,393,153, 4,180,494 and 4,034,013 add ethylene-propylene copolymers (EPR), ethylene-propylene-diene copolymers (EPDM), methacrylate-butadiene-styrene copolymers (MBS), and the like. Although a method of improving impact resistance has been proposed, these methods may improve impact resistance of a polyester resin, but have a disadvantage in that hollow moldability is deteriorated.

On the other hand, polycarbonate resin has excellent impact resistance and heat resistance but has a disadvantage of poor moldability, conventionally overcomes this through an alloy with acrylonitrile-butadiene-styrene (ABS). Polycarbonate / acrylonitrile-butadiene-styrene (PC / ABS) alloy resins have been widely used in electric / electronic and automotive applications in combination with the impact resistance and heat resistance of polycarbonate and the processability of acrylonitrile-butadiene-styrene. However, polycarbonate is expensive and has a disadvantage of requiring a large amount of polycarbonate in the alloy resin in order to obtain heat resistance.

Accordingly, many studies have been made to overcome the low impact resistance and the economical properties of the polyester resin and the hollow moldability of the alloy resin of EPR, EPDM, MBS, ABS and the like at room temperature and low temperature.

An object of the present invention is to maintain the mechanical strength, chemical resistance, etc. of the polyester-based resin, and to add a polycarbonate to compensate for the impact resistance, styrene-based rubber in order to compensate for the workability, in particular hollow moldability of the composite resin And an ethylene / alkyl (meth) acrylate polymer is added to provide a polyester-based thermoplastic resin composition which is excellent in mechanical strength, impact resistance, heat resistance and hollow moldability and has low glossiness.

The above and other objects of the present invention can be achieved by the present invention described in detail below.

One aspect of the present invention for achieving the above object is (A) 10 to 70 parts by weight of polyester resin, (B) 10 to 60 parts by weight of polycarbonate resin, (C) 5 to 50 parts by weight of styrenic rubber copolymer Part and (D) 5 to 20 parts by weight of the ethylene / alkyl (meth) acrylate copolymer.

Hereinafter, the detailed description of each component of the polyester-based thermoplastic resin composition of the present invention is as follows.

(A) polyester resin ( PEs )

The polyester resin according to the present invention is prepared by polymerizing dicarbonic acid and diol.

The dicarboxylic acid includes terephthalic acid, isophthalic acid, naphthalene dicarboxylic acid, diphenyl ether dicarboxylic acid, diphenyl dicarboxylic acid, diphenyl sulfone dicarboxylic acid, and the like.

Examples of the diol component include ethylene glycol, trimethylene glycol, tetramethylene glycol, hexamethylene glycol, neopentyl glycol, cyclohexane dimethylol, 2,2 bis (4-β hydroxy phenyl-phenyl) -propane, 4,4 Preference is given to using α, ω-diols such as -bis- (β-hydroxy epoxy) -diphenyl sulfone, diethylene glycol and the like.

The content of the polyester resin is preferably 10 to 70 parts by weight, more preferably 20 to 50 parts by weight. When the content of the polyester resin is less than 10 parts by weight, the mechanical strength is lowered, and if it is more than 70 parts by weight, the hollow moldability may be lowered.

(B) polycarbonate resin ( PC )

The polycarbonate resin according to the present invention can be prepared by reacting one of diphenols represented by the following formula with phosgene, halogen formate or diester carbonate.

Wherein, A is a cycloalkylidene, -S- or -SO ₂ of the C ₁ ~C ₅ alkylene, C ₂ ~C ₅ alkylidene, C ₅ ~C ₆ of a single bond - represents a.

Examples of the diphenol represented by Chemical Formula 1 include hydroquinone, resorcinol, 4,4'-dihydroxydiphenyl, 2,2-bis- (4-hydroxyphenyl) -propane, 2,4-bis- ( 4-hydroxyphenyl) -2-methylbutane, 1,1-bis- (4-hydroxyphenyl) -cyclohexane, 2,2-bis- (3-chloro-4-hydroxy phenyl) -propane, 2 And 2-bis- (3,5-dichloro-4-hydroxyphenyl) -propane and the like, among which 2,2-bis- (4-hydroxyphenyl) -propane and 2,2-bis- (3,5-dichloro-4-hydroxyphenyl) -propane, 1,1-bis- (4-hydroxyphenyl) -cyclohexane, etc. are preferable, and 2,2-bis- (especially called bisphenol-A is preferable. More preferably, 4-hydroxyphenyl) -propane is used.

The polycarbonate resin preferably has a weight average molecular weight of 10,000 to 200,000, more preferably 15,000 to 80,000.

In addition, a branched chain may be used as the polycarbonate resin. Preferably, the polycarbonate prepared by adding 0.05 to 2 mol% of a tri- or more polyfunctional compound based on the total amount of diphenols used for polymerization is good. Examples of the tri- or higher polyfunctional compound include those such as compounds having a trivalent or higher phenol group.

Homopolycarbonate and copolycarbonate may be used as the polycarbonate resin, and may be used as a blend form of copolycarbonate and polycarbonate, and the polycarbonate resin may be partially or entirely replaced by an ester precursor. Can be. Examples of the ester precursors include those such as aromatic polyester-carbonate resins obtained by polymerizing a bifunctional carboxylic acid.

The content of the polycarbonate resin is suitable 10 to 60 parts by weight, preferably 20 to 50 parts by weight. If the content is less than 10 parts by weight, the impact reinforcing effect is insignificant, and if it is more than 60 parts by weight, the hollowness may be reduced.

(C) Styrene series  Rubbery copolymer

The styrenic rubbery polymer according to the present invention contains a styrene monomer unit, and includes a styrene-butadiene block copolymer, a styrene-butadiene-ethylene-styrene block copolymer, an methyl acrylate butadiene styrene copolymer, an acrylonitrile-butadiene-styrene copolymer Copolymer, acrylonitrile-butylacrylate-styrene copolymer, etc. are preferable, especially the acrylonitrile-butadiene-styrene copolymer and rubber acrylonitrile-butylacrylate-styrene copolymer which are 30 to 60 weight% good. The styrenic rubbery polymers all have styrene units, providing excellent compatibility with the ethylene / alkyl (meth) acrylate copolymer (D) which is a branched styrenic copolymer.

The content of the styrene rubbery polymer is preferably 5 to 50 parts by weight, more preferably 10 to 40 parts by weight.

(D) ethylene / Alkyl (meth) acrylate  Copolymer

The ethylene / alkyl (meth) acrylate copolymer according to the present invention is represented by the following formula (2).

Wherein R ₁ is a hydrogen atom or a methyl group, R ₂ is a C ₁ to C ₁₂ alkyl group and is a hydrogen atom or methyl, ethyl, propyl, isopropyl, butyl, sec-butyl, t-butyl, isobutyl, isoamyl and a t-amyl group, m and n are degrees of polymerization, and the ratio of m and n is 300: 1 to 10:90.

The ethylene / alkyl (meth) acrylate copolymer is random, block, multiblock, graft copolymer, or a mixture thereof, and the content thereof is preferably in the range of 5 to 20 parts by weight, and is used in the range of 5 to 10 parts by weight. More preferably. It is because a hollow moldability will fall when it is less than 5 weight part, and heat resistance may fall when it exceeds 20 weight part.

The ethylene / alkyl (meth) acrylate copolymer preferably has a melt index of 0.01 to 40 g / 10 min at 190 ° C. and 2.16 kgf condition, and a melt index of 0.1 to 10 g / 10 min at 190 ° C. and 2.16 kgf condition. More preferred. If the melt index is less than 0.01 g / 10 minutes or more than 40 g / 10 minutes, the hollowness may not be uniformly mixed with (A), (B), and (C), thereby decreasing the hollowness.

The thermoplastic resin composition of the present invention contains a stabilizer and an antioxidant in addition to the (A) polyester resin, (B) polycarbonate resin, (C) styrene-based rubbery copolymer, and (D) ethylene / alkyl (meth) acrylate copolymer. , Lubricants, antibacterial agents, mold release agents, anti-dripping agents, dyes, pigments, inorganic additives, etc. can be added, each of the contents (A), (B), (C), (D) It is preferable that it is 0.1-5 weight% with respect to the whole.

The following examples and comparative examples are intended to illustrate the invention in detail and are not intended to limit the claims of the invention.

Example

(A) polyester resin, (B) polycarbonate resin, (C) styrene-based rubbery copolymer, (D) ethylene / alkyl (meth) acryl used in Examples 1 to 3 and Comparative Examples 1 to 3 below The specifications of the rate copolymer and (E) methacrylate-butadiene-styrene copolymer (MBS) are as follows.

(A) Polyester resin

TRE-DE2 manufactured by Wintech Polymer was used.

(B) polycarbonate resin

Panlite LW-1225 manufactured by Teijin was used.

(C) Styrene Rubber Copolymer

CHPC products manufactured by Cheil Industries with a rubber content of 40% were used.

(D) Ethylene / alkyl (meth) acrylate copolymer

EMA-1330 Grade was used among Elvaloy AC products manufactured by Dupont, USA.

(E) methacrylate-butadiene-styrene copolymer (MBS)

E-905 manufactured by MRC of Japan was used.

[Example 1-3]

The resin composition obtained by mixing according to the composition of each component shown in Table 1 was uniformly mixed for 3 to 10 minutes with a Henschel mixer, then introduced into a twin screw extruder, and extruded at an extrusion temperature of 250 ° C. and 250 rpm to prepare pellets.

From the pellets prepared by the above method, injection molding was carried out in a 10 Oz injection molding machine at an injection temperature of 250 ° C. and a mold temperature of 80 ° C. to prepare a physical specimen, and was evaluated after leaving for 40 hours at 23 ° C. and a relative humidity of 50%.

[ Comparative Examples 1 to 3]

Comparative Examples 1 to 3 were prepared in the same manner as in Examples 1 to 3 except that the composition of each component was changed as described in Table 1.

(Unit is by weight)

The physical properties of the specimens prepared as described above were evaluated in the following manner, and the measurement results are shown in Table 2.

(1) Tensile strength: Tensile strength was measured according to the ASTM D638 evaluation method. In particular, the higher the tensile strength value measured at 170 ° C, the better the hollowness formation.

(2) IZOD impact strength: Notched and measured in 1/8 ˝ IZOD specimen by the ASTM D256 evaluation method.

(3) Glossiness: The measurement angle was measured at 60 ° according to ASTM D523.

(4) Softening point: It measured by ISO R306 evaluation method.

From the results of Table 2, in Examples 1 to 3 using the ethylene / alkyl (meth) acrylate copolymer as the composition range of the present invention, the tensile strength at room temperature is not different as compared with Comparative Examples 1 to 3, but the heat resistance It can be seen that the tensile strength and impact strength at room temperature and low temperature are increased while maintaining the softening point without deterioration. In particular, the high temperature tensile strength is significantly increased, showing the excellent hollow formability compared to the conventional MBS, and the gloss is also reduced to show a low gloss property.

The present invention is prepared by combining the mechanical strength of the polyester resin, impact resistance and heat resistance of the polycarbonate resin, workability of the styrene-based rubbery copolymer, ethylene / alkyl (meth) acrylate copolymer, and hollow moldability, It has the effect of providing a polyester-based thermoplastic resin composition having excellent mechanical strength, impact resistance, heat resistance and hollow moldability at the same time.

Simple modifications or changes of the present invention can be easily carried out by those skilled in the art, and all such modifications or changes can be seen to be included in the scope of the present invention.

Claims (4)

(A) 10 to 70 parts by weight of polyester resin; (B) 10 to 60 parts by weight of a polycarbonate resin; (C) 5 to 50 parts by weight of the styrenic rubber copolymer; And (D) A thermoplastic resin composition comprising 5 to 20 parts by weight of an ethylene / alkyl (meth) acrylate copolymer. The method of claim 1, The polyester resin (A) is 20 to 50 parts by weight; The polycarbonate (B) resin is 20 to 50 parts by weight; The styrene rubbery copolymer (C) is 10 to 40 parts by weight; And The ethylene / alkyl (meth) acrylate copolymer (D) is composed of 5 to 10 parts by weight of a thermoplastic resin composition. The method according to claim 1 or 2, The thermoplastic resin composition, characterized in that the melt index of the ethylene / alkyl (meth) acrylate copolymer (D) is 0.01 to 40 g / 10 min at 190 ° C. and 2.16 kgf conditions. The method according to claim 1 or 2, The thermoplastic resin composition, characterized in that the melt index of the ethylene / alkyl (meth) acrylate copolymer (D) is 0.1 to 10 g / 10 min at 190 ° C. and 2.16 kgf conditions.