JP2002012748A - Resin composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a resin composition improved in flowability without detriment to the transparency and impact resistance inherent in a polycarbonate resin. SOLUTION: The resin composition comprises a mixture of 95-5 pts.wt. polycarbonate resin and 5-95 pts.wt. polyester resins, wherein at least one of the polyester resins is a polyester resin (called a PCTG) containing a dicarboxylic acid polycondensation component comprising a terephthalic acid component and at least 40 mol% 1,4-cyclohexane dimethanol, with the PCTG accounting for at least 10 wt.% of the total polyester resin component.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a resin composition, and more particularly to a resin composition having excellent fluidity without impairing the transparency and impact resistance of a polycarbonate resin.

[0002]

2. Description of the Related Art Polycarbonate resins have excellent transparency and impact resistance.
Although it is used for various purposes such as sheets, films and molded products, it has a problem that the fluidity is low and the moldability is poor.

In order to solve this problem, it has been proposed to add a polyester resin to a polycarbonate resin (JP-B-36-014035, JP-B-58-0183).
91), however, this method has a problem in that the transparency or impact resistance of the polycarbonate resin is impaired.

An object of the present invention is to provide a resin composition which improves the flowability without impairing the transparency and impact resistance of a polycarbonate resin, with the object of solving the problems of the prior art.

[0005]

As a result of intensive studies to achieve the above object, the above problems can be solved by blending a specific polyester resin with a polycarbonate resin. In particular, by blending this resin, It has been found that the contribution to solving the problem that the transparency of the polycarbonate resin is impaired is great.

That is, in the resin composition according to the present invention, in a mixed resin comprising 95 to 5 parts by weight of a polycarbonate resin and 5 to 95 parts by weight of a polyester resin, at least one of the polyester resins contains terephthalic acid and terephthalic acid. A dicarboxylic acid-based polycondensation component comprising one or more terephthalic acid-based components selected from the group consisting of derivatives and a glycol-based polycondensation component containing 1,4-cyclohexanedimethanol in an amount of 40 mol% or more. The following general formula (I) obtained by condensation

Embedded image (PCTG) having a repeating unit represented by the following formula in its structure, wherein the weight ratio of the PCTG is 10% or more of the entire polyester resin component.

As the polycarbonate resin of the present invention, those produced from a bisphenol compound by a known method can be used, and different types may be used in combination.

The polyester resin of the present invention is obtained by polycondensing a glycol-based condensation component and a dicarboxylic acid-based component. Examples of the glycol component include ethylene glycol, propylene 1,2-glycol, propylene 1,1-glycol, and the like. 3-glycol, 1,4-butadiol, 2,3
And glycol components such as butadiol and hexane 1,6-diol. Examples of the dicarboxylic acid component include isophthalic acid, terephthalic acid, orthophthalic acid, and biphenyldicarboxylic acid. These glycols and dicarboxylic acids may be used alone or in combination of two or more glycols or carboxylic acids. Further, the obtained polyesters may be used alone or in combination.

In the present invention, it is necessary to use the above-mentioned PCTG as at least one kind of polyester resin, and it is necessary to use a resin in which the weight ratio of the PCTG is 10% or more of the entire polyester resin component.

In the above-mentioned PCTG, the terephthalic acid derivative includes, for example, dimethyl terephthalate, diethyl terephthalate and the like, among which dimethyl terephthalate is preferable. As the glycol-based condensation component, 1,
It is necessary to use 40 mol% or more of 4-cyclohexanedimethanol. That is, the ratio of 1,4-cyclohexanedimethanol in the entire glycol-based condensation component is 40%.
If it is less than mol%, transparency cannot be obtained, and it is necessary to be 40 mol% or more, and it is more desirable to be 50 mol% or more. In addition, 1,4-cyclohexanedimethanol has two types of isomers, cis-type and trans-type, and any of them may be used. Examples of the glycol-based condensation component used in combination with 1,4-cyclohexanedimethanol include ethylene glycol and propylene glycol.Ethylene glycol is well-balanced in physical properties, is widely industrially produced, and is inexpensive. Particularly preferred.
Of course, 100% 1,4-cyclohexanedimethanol may be used as the glycol-based condensation component.

In the present invention, the mixing weight ratio between the polycarbonate resin and the polyester resin is from 95/5 to 5 /
95, and the weight ratio of PCTG to the entire polyester resin must be 10% or more.

When the weight ratio of the polyester resin is less than 5%, the flowability of the polycarbonate resin is not improved. On the other hand, if the weight ratio of the polyester resin exceeds 95%, the impact resistance of the polycarbonate resin cannot be maintained.

When the weight ratio of PCTG to the total polyester resin is less than 10%, the transparency of the polycarbonate resin composition according to the present invention cannot be obtained. Note that this PCTG
May be 100%.

The resin composition of the present invention may contain various additives such as an antioxidant, a plasticizer, a modifier, a light stabilizer, an ultraviolet absorber, a filler, a fluorescent brightener, and an antistatic agent. You may mix. Further, the resin composition of the present invention can be easily formed into a desired shape such as a sheet or a film by a molding machine such as an extruder, a calender, and an injection.

[0015]

Next, specific embodiments of the present invention will be described.

First, the following raw materials were used in Examples and Comparative Examples. (Polycarbonate resin) "Iupilon E2000F" manufactured by Mitsubishi Engineering-Plastics Corporation (polyester resin) (1) "PA-280" manufactured by Mitsubishi Rayon Co. (polyester resin whose dicarboxylic acid component is terephthalic acid and whose glycol component is ethylene glycol) ( 2) Toray “1401” (glycol component is 1,4)
-Polyester resin which is butanediol) (3) "H3212" manufactured by Sehan (polyester resin whose dicarboxylic acid component is isophthalic acid and whose glycol component is ethylene glycol) (4) "PCTG5445" manufactured by Eastman Chemical Company
(Polyester resin having a ratio of 1,4-cyclohexanedimethanol of 50 mol%) (5) "PETG147" manufactured by Eastman Chemical Company
1 "(when the ratio of 1,4-cyclohexanedimethanol is 3
0 mol% polyester resin)

<Examples 1 to 5 and Comparative Examples 1 to 6> Each resin was mixed at a ratio shown in Table 1 using a tumbler mixer, and dried in an oven at 120 ° C. for 24 hours. Using an injection molding machine, 1 mm thick and 5
A plate having a size of 0x100 mm was prepared, and its transparency and impact resistance were evaluated. Furthermore, the fluidity was evaluated by the above-mentioned injection molding machine. These evaluation methods are as follows.

Transparency: The haze value of the plate obtained by the above method was measured according to the method of JIS K7105. Impact resistance: In the center of the plate surface obtained by the above method,
A tip with a 1/2 inch R tip was applied, a 1 kg weight was dropped on the opposite surface of the plate, and the height at which the plate was cracked was measured. Fluidity: An injection mold having a thickness of 3 mm and a size of 15 × 200 mm was prepared, the resin composition was injection-molded in the mold, and the length of the obtained rod was measured.

[0019]

[Table 1]

As is clear from Table 1, the resin compositions of Examples 1 to 5 of the present invention have low haze value, excellent transparency, good impact resistance, and good fluidity.

On the other hand, the resin compositions of Comparative Examples 1 to 6, which deviate from the scope of the present invention, were inferior in at least one of transparency, impact resistance and fluidity. That is, in Comparative Example 1 in which the polycarbonate resin was more than the preferred range of the present invention, the fluidity was poor. In Comparative Examples 2 and 3 where the polycarbonate resin was less than the preferred range, the impact resistance was poor. In Comparative Examples 4 and 5, in which PCTG was less than the preferred range or was not contained at all, the transparency was poor.
In the glycol-based polycondensation component of the polyester resin, 1,4
Comparative Example 6, in which the content of cyclohexanedimethanol was smaller than that of PCTG, was also inferior in transparency.

[0022]

As described above, the resin composition according to the present invention maintains the transparency and impact resistance of the polycarbonate resin by blending the specific polyester resin with the polycarbonate resin, and maintains the fluidity of the polycarbonate resin. Can be improved.

Claims (1)

[Claims] (1) 95 to 5 parts by weight of a polycarbonate resin;
In a mixed resin comprising 5 to 95 parts by weight of a polyester resin, at least one of the polyester resins is a dicarboxylic acid based on one or more terephthalic acid components selected from the group consisting of terephthalic acid and terephthalic acid derivatives. The following general formula (I) obtained by polycondensing a polycondensation component with a glycol-based polycondensation component containing 1,4-cyclohexanedimethanol in an amount of 40 mol% or more; A resin composition comprising a polyester resin (referred to as PCTG) having a repeating unit represented by the following formula in its structure, wherein the weight ratio of the PCTG is 10% or more of the entire polyester resin component.