JPH062865B2 - Polyester resin composition - Google Patents

Description

The present invention relates to a polyester resin composition, particularly a polyester resin which provides a molded article having a remarkably high impact resistance, a suitable flexural modulus and an excellent appearance and color tone. It relates to a composition.

[Prior Art] A method for improving the impact strength by adding an ethylene-α olefin copolymer obtained by grafting an α, β-unsaturated carboxylic acid to polyester is known.

[Problems to be solved by the invention]

As an industrial resin, improvement in impact resistance is further required as compared with the above conventional resins.

[Means for solving problems]

The constitution of the present invention for solving the above problems is a thermoplastic polyester resin composition in which 100 parts by weight of polyester is mixed with 1 to 120 parts by weight of a modified ethylene-α olefin copolymer and 0.05 to 5 parts by weight of an epoxy compound. Is.

However, the above-mentioned modified ethylene-α olefin copolymer is an α, β-unsaturated carboxylic acid ester compound represented by the following formula, or an ethylene grafted with the α, β-unsaturated carboxylic acid or its anhydride or its ester. −
It is an α-olefin copolymer.

(Here, n represents an integer of 0 to 4, m represents an integer of 1 to 10. R ¹ and R ² represent a hydrogen atom or an alkyl group, and R ³ represents a hydrogen atom, an alkyl group or a carboxyl group.) More specifically, the thermoplastic polyester used in the present invention is a polyalkylene terephthalate obtained by a polycondensation reaction of terephthalic acid, isophthalic acid or a dialkyl ester thereof and a fatty acid glycol, or a co-polymer mainly composed of polyalkylene terephthalate. Polyethylene terephthalate, polybutylene terephthalate, and the like are typical examples of the union.

Examples of the above-mentioned aliphatic glycols include ethylene glycol, 1,4-butanedinal, an ethylene glycol adduct of tetrabromobisphenol A, propylene glycol, tetramethynylene glycol, hexamethylene glycol, and the like. And other diols or polyhydric alcohols, for example, 30% by weight or less of cyclohexanediol, cyclohexanedimethanol, xylene glycol, 2,2-bis (4-hydroxyphenyl) based on aliphatic glycols
Propane, 2,2-bis (4-hydroxy-3,5-dibromophenyl) propane, 2,2-bis (4-hydroxyethoxyphenyl) propane, 2,2-bis (4-hydroxyethoxy-3,5- Dibromophenyl) propane,
Glycerin, pentaerythritol and the like may be mixed and used.

In addition to terephthalic acid or a dialkyl ester thereof, other dibasic acid, polyhydric hydrochloric acid or an alkyl ester thereof, for example, 30% by weight or less of terephthalic acid or a dialkyl ester thereof, phthalic acid, isophthalic acid,
You may mix and use naphthalene dicarboxylic acid, diphenyl dicarboxylic acid, adipic acid, sepasic acid, trimesic acid, those alkyl esters, etc.

The modified ethylene-α olefin copolymer is a copolymer of ethylene and α-olefin having 3 or more carbon atoms (hereinafter referred to as unmodified ethylene-α olefin copolymer).
And an α, β-unsaturated carboxylic acid ester compound or the α, β-unsaturated carboxylic acid ester compound and α, β
It is obtained by grafting with an unsaturated carboxylic acid or its anhydride or its ester.

The unmodified ethylene-α olefin copolymer, which is a raw material of the modified ethylene-α olefin copolymer, is, for example, a Ziegler-Natta-type catalyst, a vanadium oxytrichloride, a vanadium compound such as vanadium tetrachloride, and an organoaluminum compound. Used, ethylene 50 mol% or more,
Preferred is a copolymer of 80 to 95 mol% and 50 mol% or less, preferably 20 to 5 mol% of α-olefin having 3 or more carbon atoms.

As α-olefin having 3 or more carbon atoms, propylene,
Examples thereof include butene-1, hexane-1, decene-1, 4-methylbutene-1, 4-methylpentene-1, and the like, with propylene or butene-1 being preferred.

Suitable examples of such unmodified ethylene-α olefin copolymers include a series of resins marketed under the trademark of Toughmer by Mitsui Petrochemical Co., Ltd., such as Tuffmer A4085, A4090, A20090, and the like. A series (ethynylene-butene-1 copolymer), Tufmer P
Examples include Tuffmer P series (ethylene-propylene copolymer) such as 0280, P0480, P0680 and P0880.

As the α, β-unsaturated carboxylic acid of the α, β-unsaturated carboxylic acid ester compound to be grafted thereto, R ¹ and R ² are hydrogen atom, methyl group or ethyl group, and R ³ is hydrogen atom, methyl group, ethyl group. Compounds which are groups or carboxyl groups, such as acrylic acid, methacrylic acid, ethacrylic acid,
Maleic acid and fumaric acid can be mentioned, m is 2
6 is preferred. As the α, β-unsaturated carboxylic acid ester, a compound represented by the following formula using acrylic acid or methacrylic acid is particularly preferable.

The graft amount of the α, β-unsaturated carboxylic acid ester compound was 0.0 with respect to the unmodified ethylene-α olefin copolymer.
1 to 2.0% by weight, preferably 0.02 to 1.8% by weight
If the amount is too small, there is no effect, and if it is too large, it becomes a gas generating source and silver is generated on the surface.

In some cases, together with the α, β-unsaturated carboxylic acid ester compound, α, β-unsaturated carboxylic acid or its anhydride or acrylic acid as its ester, which is grafted onto the unmodified ethylene-α olefin copolymer, Examples thereof include methacrylic acid, ethacrylic acid, maleic acid, fumaric acid, and anhydrides or esters of these acids.

Of these, maleic anhydride is particularly preferable.

The amount of the α, β-unsaturated carboxylic acid or its anhydride or its ester to be grafted onto the unmodified ethylene-α olefin copolymer is 0.05 to 5% by weight based on the unmodified ethylene-α olefin copolymer. is there.

In addition to the α, β-unsaturated carboxylic acid ester compound, when α, β-unsaturated carboxylic acid or its anhydride or its ester is used in combination, physical properties such as Izod impact value and tensile elongation can be obtained as will be apparent from Examples described later. improves. However, too large amount is not preferable because it causes coloring when added to the polyester resin.

It is preferably in the range of 0.07 to 3% by weight.

The grafting is carried out according to a conventional method by adding the above α, β-unsaturated carboxylic acid ester compound or the α, β-unsaturated carboxylic acid or its anhydride or its ester to the ethylene-α olefin copolymer, and usually 150 to Melt kneading is performed at 300 ° C.

The method of grafting the two kinds of compounds may be a sequential method of first grafting one and then the other. A screw type extruder is often used for this melt-kneading. Of course, an organic peroxide such as α, α′-bis-t-butylperoxy-p-diisopropylbenzene was added to the unmodified ethylene-α olefin copolymer in an amount of 0. You may use about 001-0.05 weight%.

The modified ethylene-α olefin copolymer used in the present invention has a crystallinity (measured by an X-ray method according to the description of Journal of Polymer Science, Volume XVII (1955) pages 17 to 26) of 75% or less. , Preferably 1-35%
And the melt index (M
I, ASTM D1238 57T at 190 ° C Measurement unit g / 10
Min) is 0.01 to 50, preferably 0.02 to 30.

In order to prepare a modified ethylene-α olefin copolymer having such a crystallinity and a melt index, an unmodified ethylene-α olefin copolymer having a crystallinity and a melt index in the above range can be used. Good.

Examples of the bifunctional epoxy compound used in the present invention include bisepoxydicyclopentadienyl ether of ethylene glycol, aliphatic diepoxy compounds such as butadiene diepoxyside, bisphenol A diglycidyl ether, and diglycidyl ether of phthalic acid. Such an aromatic diefoxy compound, 3,4-epoxycyclohexylmethyl-3,4-epoxycyclohexanecarboxylate,
3,4-Epoxy-6-methylcyclohexylmethyl-
3,4-epoxy-6-methylcyclohexanecarboxylate, 2,3-epoxycyclohexylmethyl-3,4-epoxycyclohexanecarboxylate, 4- (3,4-
Epoxy-5-methylcyclohexyl) butyl-3,4
-Epoxycyclohexanecarboxylate, bis (3,
4-epoxycyclohexylmethyl) adipate, bis (3,4-epoxy-6-methylcyclohexylmethyl)
Adipate, 2- (3,4 epoxycyclohexyl-5,5-
Examples thereof include alicyclic diepoxy compounds such as spiro-3,4 epoxy) cyclohexane-metadioxane and halogen-containing diepoxy compounds such as tetrabromobisphenol A diglycidyl ether. Among these, bisphenol A diglycidyl Ether is particularly preferred. The amount of the bifunctional epoxy compound added is preferably 0.05 to 5 parts by weight, particularly 0.1 to 2 parts by weight, based on 100 parts by weight of the polyester resin. If the amount is too small, the effect will not be obtained. As a result, the temperature of the resin needs to be raised during molding, which causes thermal deterioration during molding.

As a method of blending the above-mentioned additives with polyester, the final molded article can be prepared by various means at any stage until just before molding. The simplest method is a method of dry blending the polyester and the additive, but this dry blended product may be melt-mixed and extruded to form a pellet. Alternatively, a master pellet prepared by kneading a predetermined amount or more of an addition part may be prepared and blended with a polyester pellet for dilution.

To obtain the final molded product, the blended product or pellet may be supplied to a molding machine for various properties such as injection, extrusion, blow, compression, and molded according to a conventional method, but in some cases, it may be added. It is also possible to add the product by a molding machine. The blending amount of the modified ethylene-α olefin copolymer is preferably 1 to 120 parts by weight with respect to 100 parts by weight of polyester.
If it is less than 1 part by weight, the improvement effect is not sufficient, and if it exceeds 120 parts by weight, the heat resistance deteriorates. Especially preferably 5
~ 100 parts by weight.

Further, the composition of the present invention, glass fiber, reinforcing agents such as carbon fibers, clay, silica, alumina, silica-alumina, glass beads, asbestos, graphite, fillers such as gypsum, dyes and pigments, stable Known additives such as agents and antistatic agents may be used in combination.

〔Example〕

 Hereinafter, the present invention will be specifically described with reference to examples.

The amounts "%" and "parts" of the components in the examples are all by weight.

[Production of modified ethylene-α olefin copolymer]

Example 1 Ethylene-butene-1 copolymer (crystallinity 20%, MI3,6, butene-1 content 14 mol%) 100
Part α, α'-bis-t-butylperoxy-p-diisopropylbenzene (dissolved in a small amount of anton) 0.05 part tetotahydrofurfuryl methacrylate (Mitsubishi Rayon, acrylic ester THF) 1 part After blending, the mixture was extruded at 200 ° C. using a 30φ twin-screw extruder (manufactured by Nakatani Machinery Co., Ltd.) and pelletized.

The crystallinity of the produced ethylene-butene-1 copolymer of methacrylic acid tetrahydrofurfuryl ester graft was 20% and MI 2.0.

After pulverizing a part of this pellet and extracting the powder reaction product with acetone, the tetrahydrofurfuryl methacrylate grafted was quantified by IR method and found to be 0.2% based on the ethylene-butene-1 copolymer.

Example 2 A maleic anhydride-grafted ethylene-butene-1 copolymer was obtained by the same method except that 1 part of tetrahydrofurfuryl methacrylate was replaced with 0.5 part of maleic anhydride in the components of Example 1 above. The amount of grafted maleic anhydride was 0.4% by weight, the crystallinity was 20%, and the MI was 1.9.

Example 3 Maleic Anhydride Grafted Ethylene-Butene-1 Copolymer of Example 2 10
0 part α, α′-bis-t-butylperoxy-p-diisopropylbenzene (dissolved in a small amount of acetone) 0.05
Parts tetrahydrofurfuryl methacrylate 1 part Raw materials of this composition were mixed, extruded and pelletized as in Example 1.

Ethylene-butene-grafted with these two kinds of functional groups
The crystallinity of the 1 copolymer was 20%, MI 2.2, the amount of maleic anhydride was 0.35%, and the amount of tetrahydrofurfuryl methacrylate was 0.17% (each relative to the ethylene-butene-1 copolymer).

Example 4 Maleic anhydride grafted ethylene-butene-of Example 2 above
1 copolymer 100 parts α, α'-bis-t-butylperoxy-p-diisopropylbenzene (dissolved in a small amount of acetone) 0.05 part α, β-unsaturated carboxylic acid compound represented by the following formula (Nippon Kayaku) KAYARAD TC-120) 1 part Raw materials of this composition were mixed, extruded and pelletized as in Example 1.

Ethylene-butene-grafted with these two kinds of functional groups
Crystallinity of 1 copolymer is 20%, MI 2.4, amount of maleic anhydride is 0.34%, amount of α, β-unsaturated carboxylic acid compound is 0.5% (relative to ethylene-butene-1 copolymer) It was.

Examples 1 to 3 and Comparative Examples 1 to 3 Polybutylene terephthalate ([η] -1.1) 100 parts and modified ethylene-α olefin copolymer 12 parts and 2
After blending 0.5 parts of bisphenol A diglycidyl ether (Mark EP17 manufactured by Atecka Argus), which is a functional epoxy compound, and kneading into pellets at a resin temperature of 250 ° C using a 40 mmφ extruder (manufactured by Isuzu Kako). Done. Using the pellet, a resin temperature of 270 ° C. and a mold temperature of 80 ° C. with a 3.60 Z injection molding machine (Toshiba IS75PN2).
Then, a test piece for measuring physical properties was prepared. The physical properties of the test piece were as shown below.

[Effects of the Invention] As described in detail above, the polyester composition of the present invention has superior impact resistance, tensile strength, tensile elongation, etc., as compared with conventional resin compositions.

Claims (1)

[Claims] 1. The following formula (I) is added to 100 parts by weight of polyester.
An ethylene-α-olefin copolymer grafted with an α, β-unsaturated carboxylic acid ester compound represented by and / or an α, β-unsaturated carboxylic acid ester compound represented by the following formula (I) and an α, β-unsaturated compound A polyester resin composition comprising 1 to 120 parts by weight of an ethylene-α-olefin copolymer grafted with a saturated carboxylic acid or an anhydride thereof or an ester thereof and 0.05 to 5 parts by weight of a bifunctional epoxy compound. (Here, n represents an integer of 0 to 4, m represents an integer of 1 to 10, R ¹ and R ² represent a hydrogen atom or an alkyl group, and R ³ represents a hydrogen atom, an alkyl group or a carboxylic acid group.)