KR100242541B1 - Polyester-polycarbonate compounded resin composition - Google Patents

Abstract

The present invention relates to a mixed resin composition of polyester and polycarbonate, wherein the composition is (a) 90 to 96 parts by weight of a mixture of polybutylene terephthalate and polycarbonate in a 1: 1.5-3: 1 weight ratio, (b) 4-10 parts by weight of an acid-modified styrene-ethylenebutylene-styrene rubber, an acid-modified ethylene-propylene rubber, or a mixture thereof, as an impact modifier, and (c) the components (a) and (b) It is characterized by containing 0.06 to 5 parts by weight of a cyclic imino ether compound as a compatibilizer with respect to 100 parts by weight of the total amount (a + b), and excellent impact resistance can be obtained even with a small impact modifier compared to the previously proposed composition. It is possible to prevent the deterioration of moldability due to the addition of the impact resistant agent, and also to reduce the rubber component at low glass transition temperature, thereby improving mechanical strength such as heat deformation temperature, tensile strength, flexural elasticity, and the like. It is a.

Description

Polyester-Polycarbonate Mixed Resin Composition

The present invention relates to a polyester mixed resin composition, and more particularly, to a mixed resin composition of a polycarbonate resin and a polybutylene terephthalate resin having improved flow and impact properties.

In general, a mixed resin composition of a polybutylene terephthalate resin and a polycarbonate resin is a composition developed to complement the advantages and disadvantages of the polybutylene terephthalate resin and the polycarbonate resin. It is a well-known blended composition that is widely applied to a wide range of uses, such as electronics, everyday goods, sporting goods and the like.

The polybutylene terephthalate resin used in the preparation of the mixed composition is excellent in thermoplasticity and excellent in flowability compared to other resins at the time of molding, but the resin has a disadvantage of relatively poor impact resistance. , Polycarbonate resin has the advantage of excellent impact resistance characteristics, while the molecular structure is completely amorphous, plasticized by the shear force rather than heat during molding, and the stress received during molding in the orientation direction of the molecular chain or molding in the injection mold It remains intact and has very difficult molding.

The mixed composition of the two resins, which complements the disadvantages and disadvantages of the two resins, has excellent impact resistance and shows much improved moldability compared to the polycarbonate resin.

Representative methods of such compositions include the addition of vinyl-based polymers compatible with polybutylene terephthalate resins and polycarbonate resins in Japanese Patent Application Laid-Open No. 53-122926. A method of adding a polymer having a shell double structure has been proposed by US Pat. Nos. 4,180,494 and 4,654,400. However, the composition has an effect of improving impact resistance by the additives added, but the flowability decreases proportionately to the input amount, so that the effect of improving moldability is insignificant.

In summary, the present inventors judge that impact resistance and formability have inverse characteristics to each other, and to solve this problem, in order to derive a method of controlling flow and impact resistance more independently than conventional compositions. During the experiment, it was found that even if the existing acid-modified impact modifier alone or in combination with other impact modifiers, it is difficult to surpass the characteristics of currently commercialized products. In the present invention, even if the existing acid-modified impact modifier is used, it is effectively reacted with the carboxyl group bound to the dispersion modifier of the impact modifier or polybutylene terephthalate resin, so that the uniform compatibility of the mixed resin and the excellent compatibility of the impact modifier. It is possible to improve the excellent impact characteristics by reducing the amount of rubber components used to reduce the flowability, thereby deriving the characteristics showing very excellent moldability, thereby leading to the present invention.

Therefore, according to the present invention there is provided a mixed resin composition of polyester and polycarbonate containing the following components:

(a) 90 to 96 parts by weight of a mixture of polybutylene terephthalate and polycarbonate in a 1: 1.5 to 3: 1 weight ratio,

(b) 4 to 10 parts by weight of acid-modified impact modifier which is an acid-modified styrene-ethylenebutylene-styrene rubber, an acid-modified ethylene-propylene rubber or a mixture thereof as an impact modifier, and

(c) 0.06-5 weight part of cyclic imino ether compounds as a compatibilizer with respect to 100 weight part of total amounts (a + b) of the said component (a) and component (b).

Hereinafter, the present invention will be described in more detail.

In this composition, polybutylene terephthalate resin of the following structural formula (I) is used as polyester.

(Ⅰ)

The production of polybutylene terephthalate resin having such a structure can be prepared in the same manner as in a conventional polyester production method.

First, acid, glycol, catalyst and various stabilizers are added to the stainless steel reaction vessel equipped with the stirrer, and the low-molecular weight ester condensation by-products are removed out of the system while maintaining the temperature of the reaction tube at 200-230 ° C. The ester reaction proceeds, and the conversion rate of the ester reaction is terminated based on the time point when 95% or more of the theoretical flow rate of the low molecular weight ester by-product has been flowed out, and when the ester reaction is terminated, the temperature in the pipe is 250-260 ° C. While increasing, the pressure in the tube is reduced to 1 mmHg or less to induce polycondensation of the polyester.

Then, the polycondensation was carried out, and the reaction was stopped at a suitable stirring load. The vacuum was broken as nitrogen and the reactant was discharged to obtain a polyester base resin desired in the present invention. The acid component which can be used here can mainly use terephthalic acid or a lower alkyl ester alone, or a mixture with a small amount of isophthalic acid, orthophthalic acid or aliphatic carbonic acid, or a lower alkyl ester compound thereof, and a glycol component is mainly butylene glycol A mixture of single or other small amount of ethylene glycol, 1, 2- or 1, 3-propylene glycol, 1, 6-hexanediol, 1, 4-cyclohexane dimethanol, and the like can be used. The catalyst is mainly tetrabutyl titanate. It is common practice to use organic titanium compounds such as tetraisopropyl titanate and the like, and other organic tin compounds alone or a mixture of these and organic titanium compounds may be used, and alkali metals, antimony oxides and acetate compounds may also be used. Can be.

And when using an organic titanium compound, magnesium acetate can also be used as a cocatalyst.

In addition to these main components and catalysts, it is also possible to use subsidiary materials such as antioxidants, antistatic agents and various additives.

On the other hand, the viscosity of the polybutylene terephthalate used in the present invention is suitably those having an intrinsic viscosity of 0.7 to 2.0 (solvent: orthochlorophenol, 30 ° C.). The composition has a drawback in processability.

As the polycarbonate used as the mixed component with the polybutylene terephthalate resin, a general bisphenol A type polycarbonate resin was used.

In addition, the acid-modified impact modifier used in the present invention is a component having a carboxyl group in the molecular structure, styrene-ethylene butylene- styrene grafted acid, ethylene propylene rubber grafted acid, etc. The same effect can also be obtained with an acid anhydride structure formed by dehydration of two carboxylic acids.

In addition, the compatibilizer used simultaneously with such a polybutylene terephthalate resin, a polycarbonate resin, an impact modifier, and the like is a cyclic imino ether compound, and the structure thereof is represented by the following structural formula (II).

(Ⅱ)

In the formula (II), X is a divalent organic group that does not exhibit reactivity in the manufacturing process of the resin composition, and carbon number selected from ethylene, propylene, butylene, pentylene, hexamethylene, octamethylene, nonamethylene and decamethylene 2-10 aliphatic alkylene group, an arylene group selected from phenylene, naphthylene, biphenylene, and an alicyclic alkylene group selected from cyclohexylene and cyclohexanedimethylene,

A and B are nothing structures or alkylene groups, such as methylene, ethylene, propylene, butylene, and A and B may be same or different.

As the X in the compound of formula (II), phenylene which is similar to the benzene structure in the polyetherester block copolymer chain is most useful, and meta-substituents having a similar melting point range than para-substituents are particularly suitable. Moreover, as A and B, it is suitable that it is an ethylene group for the ease of reaction at the time of mixing.

When the mixed resin composition of the polybutylene terephthalate resin and the polycarbonate resin is prepared, the cyclic imino ether compatibilizer is used in an amount of about 0.06 to 5.0% by weight based on the total amount of the polybutyl terephthalate resin, the polycarbonate resin and the impact modifier. It is preferable.

If the cyclic imino ether compatibilizer is less than 0.05% by weight, it is difficult to obtain excellent impact resistance as in the conventional method, and in order to obtain high impact resistance, the content of the impact agent must be increased, resulting in a decrease in flowability. The moldability may be lowered, and when used in excess of 5.0% by weight, impact resistance and moldability may be improved, but this ideal amount does not need to be added because a proportional effect cannot be obtained with respect to the amount of the compatibilizer added.

In addition, the polycarbonate resin that can be used in the present invention is a polycarbonate resin of the conventional bisphenol A type, and is currently manufactured and supplied by many companies around the world, and the amount of the polycarbonate resin as described above is polybutylene terephthalate resin / poly The mixing ratio of carbonate resin may be mixed in a ratio of about 1: 1.5 to 3: 1. This ratio is a general mixing ratio. If the content of polycarbonate is less than this ratio, the impact resistance is lowered, and the content of polycarbonate is If it is large, there is a disadvantage in that the flowability is lowered and the moldability is poor.

In addition, the amount of impact modifier is 4 to 10% by weight relative to the total amount of polybutylene terephthalate resin, polycarbonate resin and impact modifier. If the% rule is exceeded, the impact resistance which is proportional to the content of the impact modifier to be added cannot be obtained, so it is not necessary to add it, and it may also cause the flowability to be lowered.

As described above, the cyclic imino ether compound that effectively reacts with the carboxyl group present in the acid-modifying impact modifier and the polybutylene terephthalate resin or the impact modifier in the polybutylene terephthalate resin and the polycarbonate resin mixture composition having excellent impact characteristics and moldability. When the mixed resin composition is prepared, it is possible to obtain excellent impact resistance as a small impact modifier compared to the existing proposed composition, thereby preventing the deterioration of the formability due to the addition of excessive impact resistant agent, and at the same time low glass transition temperature By reducing the rubber component of the, it is possible to obtain a mixed resin composition with improved mechanical strength, such as thermal deformation temperature, tensile strength, flexural modulus.

In addition, the mixed resin composition having such characteristics can be applied to the manufacture of large injection molding products requiring impact resistance such as automobile bumpers, automobile fenders, automobile front spoilers (also called air dams), and vehicle rear spoilers. It can also be applied to electrical and electronic applications requiring precision molding, such as fuse boxes and switch connectors.

Hereinafter, the present invention will be described in more detail with reference to Examples, but the present invention is not limited to the Examples.

Example 1

55 parts by weight of polybutylene terephthalate resin [SPESIN KP210 manufactured by Kolon, Korea] 38 parts by weight of polycarbonate resin (Iupilon S-2000, manufactured by Mitsubishi Gas Chemical Co., Ltd., Japan) 7 parts by weight of the mixed styrene-ethylenebutylene-styrene creton FG1901X were mixed well, and then introduced into the first inlet of the twin screw thermomelting kneader, and a cyclic imino ether compound as a compatibilizer was 1, 3-phenylene- Bis-2-oxazoline and tetrakis [methylene-3 (3,5-di-t-butyl-4-4-hydroxy-phenyl) propionate] methane (Sigma) Knox 1010) was introduced into the secondary inlet 1.0 parts by weight and 0.5 parts by weight with respect to 100 parts by weight of the total amount of polybutylene terephthalate, polycarbonate and impact modifier, respectively, the cylinder was 220 ° C in the rear, 260 ° C in the middle, and 265 ° C in the whole. And set to and extruded to prepare a mixed resin composition of polybutylene terephthalate and polycarbonate.

The mixed resin composition thus prepared was dried in a dehumidifying hot air dryer at 100 ° C. for 6 hours, and then a specimen for measuring physical properties was prepared in an injection molding machine having a clamping force of 150 tons. The tensile strength, flexural modulus, heat deformation temperature and impact strength were measured. The flowability was measured, and the flowability as a dried pellet was measured by the melt index, and the results are shown in Table 1 below. The measurement methods of various physical properties were measured according to ASTM shown below, and the units were as follows.

* Tensile strength: measured according to ASTM D638, unit is Kg / ㎠

* Flexural modulus: measured according to ASTM D790, unit is Kg / ㎠

* Heat distortion temperature: measured at 264psi according to ASTM D648, unit is ℃

* Impact strength: measured according to ASTM D256, unit is Kg · cm / cm

* Melt index: measured at 280 ° C with a load of 2160g according to ASTM D1238, and the unit was g / 10 min.

Examples 2 to 8 and Comparative Examples 1 to 11

In Example 1, polybutylene terephthalate resin, polycarbonate resin and impact resistant agent, and a compatibilizer and a heat resistant agent were added in the amount shown in Table 1 and was carried out in the same manner as in Example 1.

TABLE 1

※ PBT: Polybutylene terephthalate

PC: Polycarbonate

HIP: impact modifier

A: Styrene-ethylene butylene- styrene grafted with succinic acid

(Crayton FG1901X of the American shell company)

B: Ethylene Propylene Rubber Grafted with Maleic Anhydride

(VA1803 from Exxon)

C: methacrylate-butadiene-styrene rubber

D: Styrene-Butadiene-Styrene Rubber

E: ethylene-propylene rubber

CPL: compatibilizer (1, 3-phenylene-bis-2-oxazoline)

AOS: Heat Resistant (Iganox 1010, Shivagaigi, Switzerland)

※ PBT: Polybutylene terephthalate

PC: Polycarbonate

HIP: impact modifier

A: Styrene-ethylene butylene- styrene grafted with succinic acid

(Crayton FG1901X of the American shell company)

B: Ethylene Propylene Rubber Grafted with Maleic Anhydride

(VA1803 from Exxon)

C: methacrylate-butadiene-styrene rubber

D: Styrene-Butadiene-Styrene Rubber

E: ethylene-propylene rubber

CPL: compatibilizer (1, 3-phenylene-bis-2-oxazoline)

AOS: Heat Resistant (Iganox 1010, Shivagaigi, Switzerland)

Claims (2)

In the mixed resin composition of polyester and polycarbonate, (a) 90 to 96 parts by weight of a mixture of polybutylene terephthalate and polycarbonate in a 1: 1.5 to 3: 1 weight ratio, (b) 4 to 10 parts by weight of acid-modified impact modifier which is an acid-modified styrene-ethylenebutylene-styrene rubber, an acid-modified ethylene-propylene rubber or a mixture thereof as an impact modifier, and (c) A polyester-polycarbonate mixture comprising 0.06 to 5 parts by weight of a cyclic imino ether compound as a compatibilizing agent based on 100 parts by weight of the total amount (a + b) of the component (a) and the component (b). Resin composition. The polyester-polycarbonate mixed resin composition according to claim 1, wherein the cyclic imino ether compound is 1, 3-phenylene-bis-2-oxazoline.