JPS59149951A - Thermoplastic polyester resin composition - Google Patents

Abstract

PURPOSE:To provide the titled compsn. having excellent impact resistance and coatability, by blending a diene polymer, a polyfunctional epoxy compd. and a silane coupling agent with a specified thermoplastic polyester. CONSTITUTION:10-80pts.wt. diene polymer contg. 50-80wt% diene monomer such as acrylonitrile/butadiene copolymer, 0.1-8pts.wt. polyfunctional epoxy compd. such as bisphenol type epoxy resin and 0-5pts.wt. silane coupling agent such as tau-aminopropyltriethoxy silane are blended with 100pts.wt. thermoplastic polyester (e.g. polyethylene terephthalate) having an intrinsic viscosity of 0.5- 2.0dl/g prepared from a 2-4 C glycol and terephthalic acid (or ester).

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a thermoplastic polyester resin composition G that has extremely high impact resistance and excellent coating performance.

Thermoplastic polyester (hereinafter referred to as
Polyethylene terephthalate (hereinafter abbreviated as PET) and polybutylene terephthalate (hereinafter abbreviated as PBT) are representative of polyethylene terephthalate (hereinafter abbreviated as PBT), which are crystalline polymers with low water absorption and mechanical properties. Due to its excellent thermal properties, electrical properties, chemical resistance, etc., it is in the spotlight in all fields of molding materials. However, these PEs have drawbacks in impact resistance due to their crystallization behavior, and especially when notched, the impact strength is very low, and improvement thereof is strongly desired. Furthermore, PEs also has the disadvantage of poor paint adhesion when used for painting, such as exterior parts of automobiles. Therefore, attempts have been made to improve PEs by blending diene polymers with them, but it cannot be said that the improvement in impact resistance is sufficient to the extent that the decrease in thermal properties and rigidity is small.

In order to address these drawbacks, the inventors of the present invention have conducted extensive research and found that impact resistance is significantly improved by blending a polyfunctional epoxy compound as a third component into a mixture of thermoplastic polyester and diene polymer. It was discovered that the combined use of a silane camping agent has an auxiliary effect, leading to the completion of the present invention.

That is, the present invention provides thermoplastic PE51 formed from glycol having 2 to 4 carbon atoms and terephthalic acid or its ester.
00 parts by weight, 50 to 80% by weight of diene monomer
A thermoplastic polyester comprising 10 to 80 parts by weight of a diene polymer, 0.1 to 8 parts by weight of a polyfunctional epoxy compound, and 0 to 5 parts by weight of a silane coupling agent. A resin composition is provided.

The PEs used in the present invention are synthesized from terephthalic acid or its ester represented by PETS'PBT and glycol having 2 to 4 carbon atoms, and have an intrinsic viscosity [η] (phenol and tetrachloroethane). (measured at 30°C in a mixed solvent with a weight ratio of 6:4) is 0.5 to 2.0 d! /
g is usually used. If necessary, 40 mol% or less of each of the acid component and alcohol component can be added, for example, aliphatic dicarboxylic acids such as adipic acid and sebacic acid, alicyclic dicarboxylic acids such as cyclohexanedicarboxylic acid, isophthalic acid, etc. Aromatic dicarboxylic acids, alcohol components include aliphatic glycols such as ethylene glycol, 1,2-butanediol, 1,3-butanediol, 1,6-hexanediol, 1,4-cyclohexane dimetatool, etc. cycloaliphatic glycol, 4.4'
-You may substitute with aromatic glycols, such as hydroxyethyloxyphenylpropane.

Next, the diene polymer used in the present invention is a polymer containing 50 to 80% by weight, preferably 60 to 75% by weight of a diene monomer such as butadiene or isoprene. Styrene, α-
Methylstyrene, trimethylstyrene, vinyltoluene, divinylbenzene, methyl methacrylate, ethyl methacrylate, propyl methacrylate, acrylonitrile,
Examples include methacrylonitrile, and styrene, acrylonitrile, and methyl methacrylate are particularly preferred, and two or more of these may be copolymerized. The diene monomer and the monomer copolymerized therewith may be polymerized by random copolymerization, graft copolymerization, or block copolymerization, and these polymerization methods include emulsion polymerization, suspension polymerization, etc. Generally, many products produced by emulsion polymerization are readily available as commercial products.

The amount of these diene polymers to be used is usually 10 to 80 parts, preferably 30 to 60 parts, per 5100 parts by weight of PE (hereinafter referred to as parts), and if it is less than 10 parts, the impact resistance is insufficiently improved. If it exceeds 80 parts, the thermal properties and rigidity will deteriorate significantly, which is not preferable.

The polyfunctional epoxy compound used in the present invention is a compound containing two or more epoxy groups, such as known bisphenol type, novolak type, aliphatic type or alicyclic type epoxy compounds, etc. The amount used is PE
Usually 0.1 to 8 parts, preferably 2 to 5100 parts
There are 5 parts.

If it is less than 0.1 part, the impact resistance will not be improved enough, and if it exceeds 8 parts, gelation will occur within the system, resulting in poor processability, and conversely, the impact resistance will be lower than that of the appropriate amount used. There is a tendency to

The silane coupling agent used in the present invention includes:
Any of the conventionally known coupling agents such as aminosilane, epoxysilane, mercaptosilane, and vinylsilane can be used, such as γ-aminopropyltriethoxysilane, N-β-(aminoethyl)-T-aminopropyltri Methoxysilane, T-glycidoxypropyltrimethoxysilane, T-glycidoxypropyltriethoxysilane, γ-mercaptopropyltrimethoxysilane, vinyltriethoxysilane, vinyltris-2-methoxyethoxysilane, etc. In particular, aminosilane-based and epoxysilane-based coupling agents are preferred. The amount used is 0 to 5 parts, preferably 0.5 to 2 parts, based on 5100 parts of PE. If the amount exceeds 5 parts, the viscosity within the system increases significantly and molding processability is reduced, which is not preferable.

The composition of the present invention may optionally contain plasticizers, mold release agents, lubricants, heat stabilizers, antioxidants, ultraviolet absorbers, flame retardants, dyes and pigments, crystal nucleating agents, blowing agents, fillers, and reinforcing agents. Alternatively, other thermoplastic resins can be added.

To obtain the composition of the present invention, no special method is required; for example, PEs, a diene polymer, a polyfunctional epoxy compound, and a silane camping agent are mixed in a commonly used mixing machine such as a tumbler, blender, or mixer. Alternatively, a mixture of PEs, a polyfunctional epoxy compound, a silane coupling agent, and a diene polymer are simultaneously charged into an extruder from an inlet and melt-mixed using an extruder. One way to do this is to mix things up. The barrel temperature of the extruder at this time is 225 to 280°C, which can be easily obtained using a single-screw or two-wheeled extruder having a Dalmage or full-flight screw, but an extruder with high kneading properties is preferred.

The present invention will be explained in more detail below (Examples will be given).

In addition, all parts and percentages in the examples are based on one weight.

Example 1 777.5 parts of PB with intrinsic viscosity (η)=1.2, acrylonitrile-butadiene copolymer [hereinafter abbreviated as NBR].

Nisobol 0N-214 manufactured by Zeon ■, butadiene content 67%] 20 parts, bisphenol type epoxy resin (
Evicron 8501 manufactured by Dainippon Ink Chemical Industry tIll Epoxy equivalent 190) 2 parts, Epoxy silane camping agent C manufactured by Nippon Unicar ■ [IC Silane^-187) 0
．． After uniformly pre-mixing 5 parts, the thermoplastic polyester resin composition of the present invention was prepared by uniformly pre-mixing 5 parts and feeding it into a vented 40φ1 extruder equipped with a Dalmage screw heated to 250°C, and after plasticizing and kneading, cooling and pelletizing. I got it. The resulting composition exhibited high impact resistance and good paint adhesion.

Example 2 A thermoplastic polyester resin composition of the present invention was obtained in the same manner as in Example 1, except that the amounts of PBT and NBR used were changed to 62.5 parts and 35 parts, respectively. The resulting composition exhibited high impact resistance and good paint adhesion.

Example 3 A thermoplastic polyester resin composition of the present invention was obtained in exactly the same manner as in Example 1, except that the amounts of PBT and NBR used were changed to 87.5 parts and 10 parts, respectively. The resulting composition exhibited relatively good impact resistance and good paint adhesion.

Example 4 Styrene-butadiene-styrene block copolymer (hereinafter abbreviated as SBS) was used instead of NBR. Cariflex TR-1101 manufactured by Shell Chemical ■, butadiene content 70%
] A thermoplastic polyester resin composition of the present invention was obtained in exactly the same manner as in Example 1 except that the following was used. The resulting composition exhibited high impact resistance and good paint adhesion.

Example 5 Butadiene methyl methacrylate styrene graftomer (hereinafter abbreviated as MBS) was used instead of NBR. Kane Ace B-56 manufactured by Kanebuchi Chemical Industry ■, butadiene content 70%
] A thermoplastic polyester resin composition of the present invention was obtained in exactly the same manner as in Example 1 except that the following was used. The resulting composition exhibited high impact resistance and good paint adhesion.

Example 6 A thermoplastic polyester resin composition of the present invention was obtained in exactly the same manner as in Example 1, except that the amounts of PBT and bisphenol-type epoxy resin used were changed to 71 parts and 3.5 parts, respectively. The resulting composition exhibits high impact resistance,
Paint adhesion was also good.

Example 7 A thermoplastic polyester resin composition of the present invention was obtained in exactly the same manner as in Example 1, except that the amount of PBT used was changed to 73 parts and the epoxysilane coupling agent was omitted. The resulting composition exhibited high impact resistance and good paint adhesion.

Example 8 A thermoplastic polyester resin composition of the present invention was obtained in exactly the same manner as in Example 1 except that PET with [η)=1.1 was used instead of PBT. The resulting composition has high impact resistance i
The paint adhesion was also good.

Comparative Example 1 A thermoplastic polyester resin composition for comparison was obtained in exactly the same manner as in Example 1, except that the amount of PBT used was changed to 97.5 parts and NBR was omitted. The resulting composition had poor impact resistance and paint adhesion.

Comparative Example 2 A thermoplastic polyester resin composition for comparison was obtained in exactly the same manner as in Example 1, except that the bisphenol-type epoxy resin and the nigexysilane coupling agent were omitted. The resulting composition had poor impact resistance.

Comparative Example 3 A thermoplastic polyester resin composition for comparison was obtained in exactly the same manner as in Example 1, except that the amounts of PBT and NBR used were changed to 92.5 parts and 5 parts, respectively. The resulting composition had poor impact resistance and paint adhesion.

Comparative Example 4 A thermoplastic polyester resin composition for comparison was obtained in exactly the same manner as in Example 1, except that the amounts of PBT and NBR used were changed to 47.5 parts and 50 parts, respectively. The obtained composition showed high impact resistance, but the rigidity decreased significantly, and in the paint adhesion test, the test piece was deformed and sagged significantly at the baking temperature (140°C, 30 minutes), and the heat resistance was poor. It was inferior to

The measurement results of notched isot impact strength, tensile strength, and paint adhesion of test pieces obtained by injection molding the thermoplastic polyester resin compositions obtained in Examples 1 to 8 and Comparative Examples 1 to 4 are as follows. Shown in the table. In addition, as for the Izot impact strength test, Izot impact strength at 23℃ (test piece thickness 3fi and (im), -4Q℃
Izotsu impact strength (3-piece test piece thickness)
The paint adhesion test was conducted using Alkyra R as a paint.
- After applying the melamine resin base to a test piece with a thickness of 3 frames, the cured coating was baked at 140° C. for 30 minutes, and a cellophane tape peeling test was conducted on the cured coating.

Claims (1)

[Claims] Thermoplastic BoIJ ester 100 formed from glycol having 2 to 4 carbon atoms and terephthalic acid or other esters
Based on the parts by weight, 50 to 80 parts by weight of diene monomer, 10 to 80 parts by weight of diene polymer, 0.1 to 8 parts by weight of polyfunctional epoxy metal, and 17 parts by weight of silane-based adhesive agent. Impact resistance 4 characterized by containing 0 to 5 parts by weight
! Thermoplastic polyester resin composition with excellent t