JP2001040189A - Polyester resin composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an amorphous polyethylene terephthalate resin composition which is compatible with both transparency and tensile property, especially elongation at break. SOLUTION: This resin composition is composed of 1-30 wt.% of a graft copolymer (A) and 99-70 wt.% of an amorphous polyethylene terephthalate resin (B) which are obtained by polymerizing 15-60 pts.wt. of a mixture of monomers composed of 30-100 wt.% of an aromatic vinyl monomer, 70-0 wt.% of an alkyl (meth)acrylate and 0-20 wt.% of a vinyl monomer copolymerizable with them, to 40-85 pts.wt. of a butadiene copolymer composed of 30-100 wt.% of butadiene, 70-0 wt.% of an aromatic vinyl monomer, 10-0 wt.% of a vinyl monomer copolymerizable with them and 5-0 wt.% of a cross-linking monomer, and which have an average particle size of less than 0.1 μm and wherein the ratio of the particle size having 0.12 μm or more is not more than 10 wt.%.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a novel amorphous polyethylene terephthalate resin composition having excellent transparency and tensile properties.

[0002]

2. Description of the Related Art Amorphous polyethylene terephthalate resin has excellent transparency, mechanical properties and gas barrier properties, and is widely used in packaging materials such as bottles. In particular, recently, its use in sheets and films has been increasing due to its excellent transparency. However, the tensile properties of the amorphous polyethylene terephthalate resin, especially the elongation at break, are not sufficient as compared with other materials, for example, vinyl chloride and the like, and improvement is required. Conventionally, as a means for improving the impact resistance of an amorphous polyethylene terephthalate resin, many attempts have been made to improve the tensile properties by adding a rubbery polymer and a rubber-containing polymer to the amorphous polyethylene terephthalate resin. In particular, it is known that a core-shell polymer having a structure in which rubber-like polymer particles are surrounded by a glass-like polymer is effective in improving impact resistance.

[0003]

The method of adding a rubbery polymer and a rubber-containing polymer as described above is effective in improving the tensile properties, but the transparency is significantly impaired and the tensile properties and the transparent properties are deteriorated. It is not easy to balance gender. An object of the present invention is to provide an amorphous polyethylene terephthalate resin composition having improved tensile properties, particularly elongation at break, without impairing transparency.

[0004]

Means for Solving the Problems As a result of intensive studies conducted by the present inventors to achieve the above-mentioned object, the composition of the graft polymer and the amorphous polyethylene terephthalate-based resin has a specific average particle size, By using a graft polymer having a particle size distribution, it has been found that transparency and tensile properties, particularly elongation at break, can be simultaneously satisfied, and the present invention has been accomplished.

That is, the present invention relates to butadiene 30 to 100.
% By weight, 70 to 0% by weight of an aromatic vinyl monomer or an aromatic (meth) acrylate monomer, 10 to 0% by weight of a vinyl monomer copolymerizable therewith, and 5 to 0% by weight of a crosslinkable monomer % Of a butadiene copolymer, 30 to 100% by weight of an aromatic vinyl monomer, 70 to 0% by weight of an alkyl (meth) acrylate, and 0 to 100% by weight of a vinyl monomer copolymerizable therewith. Graft having an average particle size of 0.1 μm or less and a particle size of 0.12 μm or more obtained by polymerizing 15 to 60 parts by weight of a monomer mixture consisting of Copolymer (A) 1
It is a resin composition comprising about 30% by weight and 99 to 70% by weight of an amorphous polyethylene terephthalate resin (B).

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION The butadiene-based copolymer used in the graft copolymer (A) used in the present invention contains 30 to 100% by weight of butadiene and 70 to 0% of an aromatic vinyl monomer.
% By weight, 10 to 0% by weight of a vinyl monomer copolymerizable therewith, and 5 to 0% by weight of a crosslinkable monomer.

The aromatic vinyl monomer used for the butadiene copolymer is a compound having one vinylic double bond and one or more benzene nuclei in the same molecule, and specifically, styrene, 4-methoxy Styrene, 4-ethoxystyrene, 4-propoxystyrene, 4-butoxystyrene,
2-methylstyrene, 3-methylstyrene, 4-methylstyrene, 4-ethylstyrene, 2,5-dimethylstyrene, 2-chlorostyrene, 3-chlorostyrene, 4-
Chlorostyrene, 2,4-dichlorostyrene, 4-bromostyrene, 2,5-dichlorostyrene, α-methylstyrene and the like can be mentioned.

The aromatic (meth) acrylate monomer is an ester of (meth) acrylic acid and an aromatic compound having an alcoholic hydroxyl group, such as phenyl methacrylate. The use of these is preferable in terms of increasing the refractive index of the rubber particles, approaching the refractive index of the amorphous polyethylene terephthalate-based resin, and increasing the transparency.

As the copolymerizable vinyl monomer, (meth) acrylate is an ester compound of acrylic acid or methacrylic acid, specifically, methyl methacrylate, ethyl methacrylate, butyl methacrylate, methyl acrylate, (Meth) acrylic acid esters of alcohols having 1 to 8 carbon atoms such as ethyl acrylate and butyl acrylate, acrylonitrile, methacrylonitrile, vinylidene cyanate, vinyl cyanide compounds such as 1,2-dicyanoethylene, maleimide compounds, (Meth) acrylic acid and the like.

Examples of the crosslinkable monomer include, but are not limited to, divinylbenzene monoethylene glycol dimethacrylate and polyethylene glycol dimethacrylate. 5 crosslinking monomers
When used in excess of the weight%, impact strength is reduced, so that it is preferable to use in the range of 5 to 0% by weight.

The graft copolymer (A) used in the present invention is prepared by mixing 40 to 85 parts by weight of the butadiene copolymer obtained as described above with 30 to 100 parts of an aromatic vinyl monomer.
% By weight, 15 to 60 parts by weight of a monomer mixture comprising 70 to 0% by weight of an alkyl (meth) acrylate and 0 to 20% by weight of a vinyl monomer copolymerizable therewith. The particle size is 0.1 μm or less, and the ratio of particles having a particle size of 0.12 μm or more is 10% by weight or less. The method of charging the monomer mixture is not particularly limited, and a method such as continuous addition of one stage and addition of two stages is used.

(Meth) acrylic acid ester is an ester compound of acrylic acid or methacrylic acid, and specifically includes methyl methacrylate, ethyl methacrylate, butyl methacrylate, methyl acrylate, ethyl acrylate, butyl acrylate and the like. (Meth) acrylic acid esters of alcohols having 1 to 8 carbon atoms are exemplified. The aromatic vinyl compound is a compound having one vinylic double bond and one or more benzene nuclei in the same molecule, and specifically, styrene, 4-methoxystyrene, 4-ethoxystyrene, and 4-propoxystyrene. , 4-butoxystyrene,
2-methylstyrene, 3-methylstyrene, 4-methylstyrene, 4-ethylstyrene, 2,5-dimethylstyrene, 2-chlorostyrene, 3-chlorostyrene, 4-
Chlorostyrene, 2,4-dichlorostyrene, 4-bromostyrene, 2,5-dichlorostyrene, α-methylstyrene and the like can be mentioned.

Other copolymerizable components include acrylonitrile, methacrylonitrile, vinylidene cyanate, vinyl cyanide compounds such as 1,2-dicyanoethylene, maleimide compounds, (meth) acrylic acid and the like.

If the average particle diameter of the graft copolymer exceeds 0.1 μm, or if 10% by weight or more of particles having a particle diameter of 0.12 μm or more is contained, transparency is impaired. 1 μm or less and particle size of 0.12 μm
It is preferable that the ratio of particles having a particle size of m or more is 10% by weight or less.

The amorphous polyethylene terephthalate resin modified by the present invention has substantially no crystallinity, or has low transparency and good transparency.
% Mol or more of ethylene glycol;
A homopolymer, a copolymer or a mixture thereof obtained by polycondensation of a dicarboxylic acid whose terephthalic acid or its alkyl ester is 0% or more can be mentioned as the copolymer. Or a copolymer of isophthalic acid or halogenated terephthalic acid, or a copolymer of poly (alkylene glycol), specifically diethylene glycol, in a range of 50 mol% or less of the total diol, or And C3-C12 alkylene glycols, for example, those obtained by copolymerizing 1,4-cyclohexanedimethanol.

The graft copolymer (A) of the present invention can be obtained by emulsion polymerization, suspension polymerization, solution polymerization or the like, but emulsion polymerization is preferred. The emulsion polymerization is produced by a known emulsification method and polymerization sequence.

As a method for producing the resin composition of the present invention, the components (A) and (B) are each separately produced in advance and then mixed using a conventional blending method such as a Henschel mixer or a tumbler. Thereafter, a method of shaping with a device used for normal shaping such as a single-screw extruder or a twin-screw extruder Banbury mixer to form a resin composition can be adopted. Further, the resin composition of the present invention may be used as an ordinary additive such as an antioxidant, a heat stabilizer, a light resistance improver, an ultraviolet absorber, a lubricant, a plasticizer, a release agent, an antistatic agent, and a sliding agent. It is permissible to add a property improver, a colorant, and the like.

[0018]

The present invention will be described in detail with reference to the following examples.
In the Examples and Comparative Examples, various physical properties were evaluated by the following methods. Parts and% represent parts by weight and% by weight, respectively, unless otherwise specified.

Average particle size, particle size distribution The latex of the graft copolymer was measured with a particle size analyzer UPA manufactured by Microtrac.

Elongation at break Measured at room temperature (23 ° C.) according to ASTM D638. The test pieces were measured using a 1/8 "ASTM Type I dumbbell.

Transparency Measured according to ASTM D-1003. The test piece is 3mm
Thick injection molded products were used.

(Example 1) 200 parts of pure water, 1.5 parts of sodium oleate, 0.002 parts of ferrous sulfate, 0.005 parts of ethylenediaminetetraacetic acid · 2Na salt
Part, sodium formaldehyde sulfoxylate 0.2
Part, tripotassium phosphate 0.2 part, butadiene 60 parts, styrene 40 parts, divinylbenzene 1.0 part and diisopropylbenzene hydroperoxide 0.1 part are charged into a polymerization vessel equipped with a stirrer, and polymerized at 50 ° C. for 15 hours. A rubber latex (a) having a conversion of 99% and an average particle diameter of 0.08 μm was obtained.

180 parts of the above rubber latex (a) (60 parts of solid content), 200 parts of pure water, 0.002 parts of ferrous sulfate,
Ethylenediaminetetraacetic acid 2Na
0.004 parts of salt and 0.1 part of sodium formaldehyde sulfoxylate are mixed, and a mixture of 28 parts of styrene, 12 parts of methyl methacrylate and 0.2 part of cumene hydroperoxide is continuously added at 70 ° C., A latex of the graft copolymer was obtained. The obtained graft copolymer latex was coagulated with hydrochloric acid, heat-treated, washed, dehydrated and dried to obtain a powdery graft copolymer.

Amorphous polyethylene terephthalate resin
(Estar6 manufactured by Eastman Chemical Company)
763) 20 parts of the above graft copolymer was added to 80 parts and premixed, and a 40 mm single screw extruder manufactured by Tabata Machinery Co., Ltd.
The mixture was melt-kneaded at a set temperature of 220 ° C. to obtain pellets. After drying the obtained pellet at 70 ° C. for 5 hours or more, 160 t
Using an injection molding machine, cylinder temperature 240 ° C, mold temperature 4
1/8 "dumbbell at 0 ° C, 100mm x 100mm x 3
A flat plate specimen having a thickness of mm was obtained. Table 1 shows the particle size and particle size distribution of the obtained graft copolymer and the values of the light transmittance and elongation at break of the resin composition.

Example 2 200 parts of pure water, 8.0 parts of sodium oleate, 0.002 parts of ferrous sulfate, 0.005 parts of ethylenediaminetetraacetic acid · 2Na salt
Part, sodium formaldehyde sulfoxylate 0.2
Part, tripotassium phosphate 0.2 part, butadiene 60 parts, styrene 40 parts, divinylbenzene 1.0 part and diisopropylbenzene hydroperoxide 0.1 part are charged into a polymerization vessel equipped with a stirrer, and polymerized at 50 ° C. for 15 hours. A rubber latex (b) having a conversion of 99% and an average particle diameter of 0.05 μm was obtained.

180 parts of the above rubber latex (b) (solid content: 60 parts), 200 parts of pure water, 0.002 parts of ferrous sulfate,
Ethylenediaminetetraacetic acid 2Na
0.004 parts of salt and 0.1 part of sodium formaldehyde sulfoxylate are mixed, and a mixture of 28 parts of styrene, 12 parts of methyl methacrylate and 0.2 part of cumene hydroperoxide is continuously added at 70 ° C., A latex of the graft copolymer was obtained. The obtained graft copolymer latex was coagulated with hydrochloric acid, heat-treated, washed, dehydrated and dried to obtain a powdery graft copolymer. Example 1
Blended with amorphous polyethylene terephthalate resin,
A resin composition was obtained in the same manner. Table 1 shows the particle size, particle size distribution, light transmittance and elongation at break of the resin composition of the obtained graft copolymer.

Comparative Example 1 Rubber Latex (a) 180
Parts (solid content 60 parts), pure water 200 parts, ferrous sulfate 0.0
02 parts, 0.004 part of ethylenediaminetetraacetic acid.2Na salt, 0.1 part of sodium formaldehyde sulfoxylate and 2.3 parts of potassium chloride were mixed at 70 ° C., 28 parts of styrene, 12 parts of methyl methacrylate and A mixture of 0.2 parts of cumene hydroperoxide was continuously added to obtain a latex of a graft copolymer. The obtained graft copolymer latex was coagulated with hydrochloric acid, heat-treated, washed, dehydrated and dried to obtain a powdery graft copolymer.

Then, a resin composition was obtained in the same manner as in Example 1. Table 1 shows the particle size and particle size distribution of the obtained graft copolymer and the values of the light transmittance and elongation at break of the resin composition.
Shown in

Comparative Example 2 A graft copolymer was obtained in the same manner as in Comparative Example 1 except that 1.2 parts of potassium chloride was used.

Then, a resin composition was obtained in the same manner as in Example 1. Table 1 shows the particle size and particle size distribution of the obtained graft copolymer and the values of the light transmittance and elongation at break of the resin composition.
Shown in

(Comparative Example 3) Only an amorphous polyethylene terephthalate resin (Estar6763 manufactured by Eastman Chemical Co.) was dried at 70 ° C. for 5 hours or more, and a cylinder temperature of 240 was obtained using a 160-t injection molding machine.
1/8 "dumbbell at 100 ° C, mold temperature 40 ° C, 100mm ×
A flat test piece of 100 mm × (thickness) 3 mm was obtained. Table 1 shows the values of the light transmittance and elongation at break of the obtained molded article.

[0032]

[Table 1]

[0033]

According to the present invention, a resin composition having improved impact resistance without significantly impairing the optical properties of the amorphous polyethylene terephthalate resin is obtained and is industrially useful.

Claims (1)

[Claims] 1 to 30% by weight of butadiene, 70 to 0% by weight of an aromatic vinyl monomer or an aromatic (meth) acrylate monomer, and a vinyl monomer 1 copolymerizable therewith.
40 to 85 parts by weight of a butadiene copolymer comprising 0 to 0% by weight and 5 to 0% by weight of a crosslinkable monomer, 30 to 100% by weight of an aromatic vinyl monomer and 70 to 70% by weight of an alkyl (meth) acrylate Monomer mixture consisting of 0% by weight and 0 to 20% by weight of a vinyl monomer copolymerizable therewith
The average particle size obtained by polymerizing parts by weight is 0.1 μm or less, and the ratio of particles having a particle size of 0.12 μm or more is 10
1 to 30% by weight of a graft copolymer (A) of not more than 100% by weight and an amorphous polyethylene terephthalate-based resin (B) 99 to
A resin composition comprising 70% by weight.