JPS63258948A - Impact-resistant polyester resin composition - Google Patents

Abstract

PURPOSE:To obtain the titled composition outstanding in operational stability and releasability, good in gloss of the molded articles therefrom, by incorporating polyethylene terephthalate with a specific nucleating agent, each specific two kinds of copolymer, plasticizer, etc. CONSTITUTION:The objective composition can be obtained by incorporating 100pts.wt. of polyethylene terephthalate with (A) 0.05-10pts.wt. of one kind of substance selected from inorganic crystal nucleating agents with an average size <=50mu and organic compounds having metal salt of carboxyl group, (B) 3-30pts.wt. of a copolymer prepared by copolymerization between ethylene and alpha,beta-unsaturated dicarboxylic anhydride with the copolymerization ratio for said anhydride being such as to be 0.01-20mol.%, (C) 1-30pts.wt. of a second copolymer from 80-99wt.% of alpha-olefin, 1-20wt.% of glycidyl methacrylate and 0-19wt.% of vinyl acetate, (D) 0.3-10pts.wt. of an ester plasticizer and (E) 0-150pts.wt. of fibrous reinforcer.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a polyester resin composition that has good moldability and provides a molded article with excellent F4 impact strength and heat resistance. More specifically, the crystallization rate is high,
The present invention relates to an impact-resistant polyester resin composition that exhibits excellent mold releasability even at a mold temperature of about 120°C or less during injection molding, and provides molded products having excellent impact strength and high heat distortion temperature. .

(Prior Art) Polyethylene terephthalate has excellent mechanical properties, electrical properties, heat resistance, chemical resistance, etc., and is used in many industrial products as #3i fibers and films.

In this way, when used as fiber or film, 1
Normally, stretched products are used, but if the product is to be used for plastic purposes as an injection molded product, for example, it is not subjected to the above stretching process.
It is known that some problems occur in terms of molding and physical properties. In other words, since the crystallization rate at low temperatures is low, 1 the crystallization rate is insufficient at mold temperatures of about 120°C or lower, which are normally used when injection molding other plastics, and the resulting molded product has There is a difference in the degree of crystallinity inside the mold, which results in uneven mechanical properties, dimensional stability, and shape stability, making it extremely difficult to obtain a molded product that can withstand practical use.

As a conventional method to solve such problems.

Many methods have been proposed, such as using a high-temperature mold, adding a crystal nucleating agent or crystallization accelerator, and blending an ethylene terephthalate copolymer with excellent low-temperature crystallinity, all of which have proven to be quite effective. It recognized. Polyethylene terephthalate or compositions sufficiently crystallized in this way, especially those blended with fibrous reinforcing materials such as glass fiber, exhibit excellent mechanical properties and high heat distortion temperatures, and have established themselves as engineering plastics. It has arrived today.

However, a disadvantage of polyethylene terephthalate compositions or reinforced polyethylene terephthalate compositions blended with glass fiber, etc., is that they have low resistance (H-type strength, that is, poor toughness), and there is a strong desire to improve this. This is the current situation.

Various proposals have been made to solve the above problems, that is, to improve impact strength. For example, JP-A-51-144452, JP-A-52-3
No. 2045, JP 58-17148, JP 5B-17151 II, USP 4,284,
No. 540 and USP No. 4,461,871 disclose a copolymer 5 having a glycidyl group in polyester.
For example, it has been proposed that the fIi impact strength can be improved by blending an ethylene/vinyl acetate/glycidyl (meth)acrylate copolymer. However, olefin polymers are copolymerized with glycidyl (meth)acrylate.

In other words, when a polyolefin having an epoxy group is blended with polyethylene terephthalate (hereinafter abbreviated as PET), although the impact resistance strength is improved, the mold releasability from the mold during molding becomes extremely poor, and the low-temperature mold 1, for example, the metal Mold temperature 1
There is a problem in that the surface gloss is poor at temperatures below 20°C. An even bigger problem is that when a polyolefin having an epoxy group is blended with PUT and heated and kneaded in an extruder to produce pellets, some gel-like substances are generated, and in some cases, many gel bodies are formed. There is a problem that the plant cannot operate due to the generation of m.

(Problems to be Solved by the Invention) The purpose of the present invention is to solve the problems of the prior art as described above, and to provide a molded product with excellent operational stability, good gloss and mold releasability, and excellent impact strength. The object of the present invention is to obtain a polyethylene terephthalate resin composition.

(Means for solving the problems) As a result of conceptual research aimed at solving the various problems mentioned above, it has been found that all such problems can be completely solved by adding specific other constituents to PIET. This is what we discovered and arrived at the present invention.

That is, the present invention uses polyethylene terephthalate 100
For every 11 parts of ff, 0.05% of at least one of (a) an inorganic crystal nucleating agent with an average particle size of 50 μm or less, an organic compound having a metal salt of a carboxyl group, and a polymer compound having a metal salt of a carboxyl group. ~IO parts by weight, C port) In an ethylene copolymer obtained by copolymerizing ethylene, one or more α, β-unsaturated dicarboxylic acid anhydrides, and optionally further α, β-unsaturated carboxylic acid esters. , the copolymerization ratio of α,β-unsaturated dicarboxylic acid anhydride is 0.
01 to 20 mol%, 3 to 30 square parts, (c)
α-olefin 80-99% by weight, glycidyl methacrylate or glycidyl acrylate 1-20% by weight
and copolymer 1-1 consisting of 0-19% by weight of vinyl acetate
The present invention relates to an impact-resistant polyester resin composition containing 30 parts by weight of 1 (0.3 to 10 parts by weight of gradient ester plasticizer and (e) 0 to 150 parts by weight of fibrous reinforcing material).

The PUT used in the present invention is obtained by melt polymerization of terephthalic acid or its ester derivative and ethylene glycol, or by solid phase polymerization thereof, and its molecular weight is not particularly limited. Further, other copolymerization components may be copolymerized as necessary.

The inorganic compound used as component (a) of the present invention is as follows.

The effect as a crystal nucleating agent varies depending on the particle size, and if the average particle size exceeds about 50 μm, the effect decreases, so in general, inorganic compounds with an average particle size of 50 μm or less are useful.

Specific examples of inorganic compounds with an average particle size of 50μ or less used in the present invention include carbon blank, silica, calcium carbonate, synthetic silicic acid and silicates, zinc white, hallosite clay, kaolin, basic carbonate, etc. Magnesium, mica.

Examples include talc, quartz powder, diatomaceous earth, dolomite, titanium oxide, zinc oxide, antimony oxide, barium sulfate, calcium sulfate, alumina, calcium silicate, etc., and one or more of these inorganic compounds are used. Although you can.

Among them, mica, kaolin, talc, and silica are useful in the present invention.

Further, as the organic compound having a metal salt of a carboxyl group used in the present invention, any compound having a metal salt of a carboxyl group can be used. 7 to 30 higher fatty acids, metal salts of aromatic acids are used, such as heptanoic acid,
pelargonic acid.

Lauric acid, myristic acid, palmitic acid, stearic acid, behenic acid, cerotic acid, montanic acid.

Metal salts of higher fatty acids such as melisic acid, benzoic acid.

Terephthalic acid, terephthalic acid monomethyl ester.

Specific examples include metal salts of aromatic acids such as isophthalic acid and monomethyl ester of isophthalic acid.

The polymer compound having a metal salt of a carboxyl group is not particularly limited as long as it has a metal salt of a carboxyl group at the end or side chain of the polymer, but for example, it can be obtained by oxidizing polyethylene 1/2. carboxyl group-containing polyethylene obtained by preparing polypropylene with an acid, carboxyl group-containing polypropylene obtained by preparing polypropylene with an acid, copolymers of olefins such as ethylene, propylene, butene-1, and (meth)acrylic acid, and copolymers of olefins and maleic anhydride. Specific examples include metal salts such as copolymers of styrene and (meth)acrylic acid, and copolymers of styrene and maleic anhydride.1 Usually, olefins and (meth)acrylic acid or styrene and (meth) ) Metal salts of copolymers of acrylic acid are used. As metals that form salts with carboxyl groups, alkaline earths, alkali metals, etc. are usually used, but alkali metals are most effective as mucous cough medicines, and among them, sodium and potassium are useful. be.

In the present invention, the α1β-unsaturated dicarboxylic acid anhydride, which is a copolymerization component of the acid anhydride-containing ethylene copolymer that is the component (b), is expressed by the following formula (wherein Rs and Rho are hydrogen, an alkyl group, or a halogen group). Examples include maleic anhydride, methylmaleic anhydride, chloromaleic anhydride, citraconic anhydride, butynylsuccinic anhydride, and tetrahydrophthalic anhydride.

α and β used as necessary as copolymerization components of the acid anhydride-containing ethylene copolymer used in the present invention
- Specific examples of unsaturated carboxylic acid esters include methyl methacrylate, ethyl methacrylate, butyl methacrylate, 2-ethylhexyl methacrylate, and 2-ethyl methacrylate.
- methacrylic esters such as hydroxyethyl, acrylic esters such as ethyl acrylate, butyl acrylate, 2-ethylhexyl acrylate, 2-hydroxyethyl acrylate, etc., or mixtures thereof. Further, as a monomer copolymerizable with ethylene, α,β-unsaturated carboxylic acid ester, and α,β-unsaturated dicarboxylic acid anhydride, styrene is used.

Styrenic compounds such as α-methylstyrene and vinyltoluene, α such as acrylonitrile and methacrylonitrile,
β-unsaturated nitrile, acrylic acid.

Examples include α, β-unsaturated carboxylic acids such as methacrylic acid, vinyl acetate, vinyl ether, etc., and these can be copolymerized as necessary.

The copolymerization ratio of α,β-unsaturated dicarboxylic acid anhydride in the acid anhydride-containing ethylene copolymer used in the present invention is 0.01 to 20 mol%, preferably 0.1 to 10 mol%.
It is mole%. As a method for producing such an acid anhydride-containing ethylene copolymer, a so-called known radical copolymerization method is used, as well as a method in which a radical generator is present in ethylene or an ethylene copolymer, and an unsaturated polymer having the above-mentioned groups is produced. Examples include a method in which one or more monomers are subjected to a radical graft reaction in the presence or absence of a solvent or dispersion medium. Among these, when grafting is performed in a molten state, the desired product can be obtained in a very short time with a simplified procedure by using a melt kneader such as an extruder, kneader, or panburi mixer.

α-olefin-glycine (meth)acrylate copolymer or α-olefin used as a component in the present invention
The content of glycidyl (meth)acrylate in the olefin-glycidyl (meth)acrylate-vinyl octate copolymer is 1 to 20% by weight, preferably 1 to 10% by weight, and when it is 1% by weight or less, the above-mentioned ethylene When used in combination with a copolymer, there is no sufficient effect in improving impact resistance, and if the amount is 20% by weight or more, side reactions such as gelation occur during the production of the resin composition of the present invention, which is not preferable.

The α-olefin components in these copolymers include ethylene, propylene, butene-1, and the like.

The vinyl acetate component in the terpolymer is 0.1 to 191
%. If the vinyl acetate content exceeds 19% by weight, it is not preferred because the thermal stability of the resulting resin composition decreases. (2) Various ester plasticizers can be used as the component, but among them, the following general formulas (1) and (11)
, (III) are particularly useful.

R+: alkylene group R2, R3: a group selected from an alkyl group, a benzyl group, and an aromatic benzyl group.

R2 and R3 are the same or different groups It is.

m *n: integer of 1 or more (IT) X: direct bond, alkylene group, -302-1-S-1
-0- or -C- R4, Rs: A group selected from an alkyl group, a benzyl group, a phenyl group or a derivative thereof, and R4 and R5 are the same or different groups.

Rs, R7: hydrogen, alkyl group, or halogen, and R6 and R7 are the same or different groups.

m, n: integers of 1 or more Ra, Rs: hydrogen, alkyl group, phenyl group.

Benzyl group or these derivatives A group selected from conductors, R6゜ Rs are the same or different groups Ru.

Rho: A group selected from a phenyl group, a benzyl group, or a derivative thereof.

R6: A group consisting of hydrogen, an alkyl group or a group defined by RIo.

n: An integer of 4 or more.

In the ester plasticizer represented by the general formula (I), R1 represents an alkylene group, usually having 1 to 20 carbon atoms.
It is desirable to use a linear or branched alkylene group having molecular symmetry. Ih.

R3 is methyl, ethyl, propyl, butyl.

Specific examples include pentyl, hexyl, heptyl, octyl, and benzyl. Regarding m and n, there is a tendency that the larger m and n, the greater the effect as a crystallization promoter, but conversely, the compatibility with P[T and heat resistance decreases. Usually m, n is 1 to about 20. Preferably it is 1 to about 10.

In general formula (II), X is usually an alkylene group such as methylene, ethylene, propylene or -0-
is useful, and as R4 and R5, alkyl groups having 5 or more carbon atoms, benzyl groups, and phenyl groups are usually effective, and m and n are 1.
~10 is desirable.

In the general formula (Iff), Re and Rs are hydrogen and alkyl groups, and RIo +
A benzyl group is useful as R, +g. If n is 3 or less, it tends to volatilize during heating and has a small effect as a crystallization promoter, so n is 4 or more and 1. For example, adipic acid,
Dibenzyl esters of azelaic acid, decane-1,10-dicarboxylic acid, octadecane-1,18-dicarboxylic acid are useful.

Specific examples of the fibrous reinforcing material used in the present invention include glass fibers, carbon fibers, aromatic polyamide fibers, silicon carbide IJ, carbon fibers, and titanate fibers; however, glass fibers are usually used. commonly used. There are no particular restrictions on the diameter and length of the various fibers;
It is difficult to mix and disperse the ingredients uniformly, and conversely, if the fiber length is too short, the effect as a reinforcing material will be insufficient.1 Usually, fibers with a fiber length of 0.1 to 10 mm are used. When the fibrous reinforcement material is glass fiber, the fiber length is preferably 0.1 to 7 mm, more preferably 0.3 to 7 mm.
4mm is desirable. In addition, the fibrous reinforcing material can be treated with various compounds as necessary for the purpose of improving the interfacial adhesion with polyester and increasing the reinforcing effect, but the uA fibrous reinforcing material When using glass fibers, two types of surface treatment agents are used, such as vinyltriethoxysilane, γ-meccryloxypropylmethoxysilane, β-(3°4-epoxycyclohexyl)-ethyltrimethoxysilane, and γ-glyside. Treated with a silane-based treatment agent such as xypropyltrimethoxysilane, γ-aminopropyl 1-ethoxysilane, T-chloropropylmethoxysilane, γ-mercaptopropyltrimethoxysilane, or a chromium-based treatment agent such as methacrylate chromic chloride. things are used.

Regarding the blending amount of each component of the present invention,! (+Ingredients.

That is, the blending amount of the inorganic crystal nucleating agent and the metal salt of carboxyl group is ppr 100 ffi parts.

If it is less than 0.05 parts by weight, it will not be effective as a crystal nucleating agent, and conversely, if it is added in more than 10 parts by weight, the effect as a crystal nucleating agent will not be better than if it is less than 10 parts by weight. This is not preferable because it may induce a decrease in impact strength.

Therefore, the blending amount of component (a) is 0.05 to 10
Parts by weight, preferably 0.5 to 5 parts by weight. If the amount of component (b), that is, the ethylene copolymer containing α,β-unsaturated dicarboxylic acid anhydride, is less than 3 parts by weight per 100 parts by weight of polyester, the effect of the combination with component (b) The improvement in impact resistance strength is small.

On the other hand, if the amount is more than 30 parts by weight, the thermal properties of the composition will deteriorate, which is not preferable. Therefore, the blending amount of component (iii) is 3 to 30 parts by weight, preferably 5 to 25 parts by weight, and more preferably 5 to 20 parts by weight.

Regarding the blending amount of component (b), that is, the glycidyl (meth)acrylate copolymerized polyolefin, if it is less than 1 part by weight, the effect of improving impact strength will be small, and even if it is blended in more than 30 parts by weight, the impact strength will increase with the blending amount. It is not preferable because it shows a saturation value and promotes gelation when heated and cross-wired.

Therefore, the blending amount of component (1) is 1 to 30 parts by weight, preferably 3 to 20 parts by weight, and more preferably 3 to 10 ffl.
It is 1 part of ff. The mixing ratio of component (B) and component (C) is 10:1 to 1:10. Preferably 10;
1 to 1:2. Particularly preferably, a range of 5:1 to 1:1 is effective for improving the targeted impact strength.

Regarding the blending amount of component (b), that is, the ester plasticizer, if it is less than 1 part of 0.3ffi, the effect of promoting crystallization and the effect of improving mold releasability will be small, and if it is blending more than 10 parts by weight, the heat resistance will decrease, which is not preferable. therefore(/
The amount of component X) is 0.3 to 10 parts by weight.

Preferably it is 1 to 7 parts by weight. Furthermore, (e) regarding the amount of fibrous reinforcing agent, if it exceeds 1150 parts by weight, tx
Since it is difficult to uniformly disperse and mix it in a fat cloth, 150 parts by weight or less per package contains 100 parts by weight or less.

Furthermore, various inorganic or organic compounds such as antioxidants, ultraviolet absorbers 1 colorants, fillers, etc. may be added to the composition of the present invention, if necessary, within a range that does not significantly reduce the impact strength. be able to. The method for producing the composition of the present invention is not particularly limited, and may be produced in various forms,
For example, it can be molded into various molded products, sheets, fibrous materials, tubular materials, and the like.

(Actual Fit Example) Next, the present invention will be specifically explained with reference to Examples and Comparative Examples.

Note that "parts" shown in Examples and Comparative Examples indicate "parts by weight."

Examples 1-5. Comparative Examples 1 to 3 Intrinsic viscosity (F,Nol/Tetrachloroethane-6/4
(measured at medium, concentration 0.5%, temperature 20°C) P of 0.68
To 100 parts by weight of UT, predetermined amounts of a crystal nucleating agent, a plasticizer, an ethylene copolymer, and a glycidyl methacrylate copolymerized polyolefin (GM copolymer) are mixed as shown in Table 1. Using a directional rotating twin-screw extruder, the cylinder temperature was 260°C.

Extrusion by kneading at a screw rotation speed of 200 rpm.

A pellet was created. Example 1 during pellet production
-5 and Comparative Examples 1 and 2 showed good operational stability, whereas 2. In Comparative Example 3, generation of a gel-like substance was observed.

After drying the pellets under reduced pressure, the cylinder temperature was 260°C, the mold temperature was 110°C, and the cooling time was 20 seconds.
A 2 inch x 2.5 inch specimen was formed.

The notched Izot impact strength at room temperature was measured according to ASTM I)-638, and the surface gloss was further evaluated.

And the mold release property is 10cm long x 7cm wide at mold temperature 105℃.
The evaluation was based on the minimum cooling time at which mold release was possible when a box-shaped molded product of m×depth 4 cm (wall thickness, 5 mm) was molded. The shorter the minimum cooling time, the better the mold releasability.

The results are summarized in Table 1.

Table 1 Reference example 1 Ethylene-maleic anhydride-acrylic acid copolymer (manufactured by Sumika CDI', Bondine X 8040) Reference example 2 Ethylene-maleic anhydride-acrylic acid copolymer (manufactured by Sumika CDF, Inc., Bondine X 8040) Bondine IIX 8140) Reference example 3 Ethylene-maleic anhydride-acrylic acid copolymer (manufactured by Sumika C-Ko, Bondine TX 8030) Reference example 4 Ethylene-maleic anhydride-acrylic acid copolymer (manufactured by Sumika CDF) , bondine Dibenzyl ester of acid Copolymer Surlyn 1555: Ethylene-acrylic acid copolymer sodium salt (manufactured by DuPont) Example 6. Comparative Example 4 The composition shown in Example 1 was further blended with glass fiber (Asahi Fiberglass (11.3 mm long chopped strand, product number Na429) in an amount of 30% by weight in the total composition, and biaxial Pellets were prepared by kneading with an extruder (Example 6). Similarly, for comparison, pellets containing 30% by weight of glass fibers having the composition shown in Comparative Example 1 were prepared. Comparative Example 4), cylinder temperature 240-260 Various test pieces were molded at -260℃, mold temperature 105℃, and cooling time 10 seconds, and the notched iso impact strength (specimen thickness 2172 inches) and 18.56 Kg/cnl were obtained according to 8STH.
The heat distortion temperature under load (specimen thickness 8178 inches) was measured.

Further, the mold releasability was evaluated based on the minimum cooling time during box molding at a mold temperature of 90° C. according to the method described above.

Table 2 (Effects of the Invention) As specifically shown in the examples, the impact-resistant polyester resin composition of the present invention has improved operational stability by incorporating specific constituent components into l'ET.

The molded product has good appearance and mold releasability, and has extremely high impact strength.

Claims (6)

[Claims] (1) For 100 parts by weight of polyethylene terephthalate, (a) an inorganic crystal nucleating agent with an average particle size of 50 μm or less, an organic compound having a metal salt of a carboxyl group, and a polymer compound having a metal salt of a carboxyl group. Obtained by copolymerizing 0.05 to 10 parts by weight of at least one type of (b)ethylene, one or more α,β-unsaturated dicarboxylic acid anhydrides, and optionally further α,β-unsaturated carboxylic acid esters. In the ethylene copolymer, the copolymerization ratio of α,β-unsaturated dicarboxylic acid anhydride is 0.01 to 20 mol%
3 to 30 parts by weight of (c) α-olefin 8
0-99% by weight, 1-30 parts by weight of a copolymer consisting of 1-20% by weight of glycidyl methacrylate or glycidyl acrylate and 0-19% by weight of vinyl acetate, (d) 0.3-10 parts by weight of an ester plasticizer, (e) An impact-resistant polyester resin composition containing 0 to 150 parts by weight of a fibrous reinforcing material. (2) The ester plasticizer has the following general formula (I) or (II)
The polyester resin composition according to claim 1, which is an ester compound of at least one of (III). ▲There are mathematical formulas, chemical formulas, tables, etc.▼ (I) R_1: Alkylene group R_2, R_3: Groups selected from alkyl groups, benzyl groups, and aromatic substituted benzyl groups, and R_2 and R_3 are the same or different groups. m, n: Integer greater than or equal to 1 ▲ Numerical formulas, chemical formulas, tables, etc. are available ▼ (II) X: Direct bond, alkylene group, -SO_2-, -S-,
-O- or ▲ Numerical formula, chemical formula, table, etc. ▼ R_4, R_5: A group selected from an alkyl group, a benzyl group, a phenyl group, or a derivative thereof, and R_4 and R_5 are the same or different groups. R_6, R_7: hydrogen, alkyl group, or halogen, and R_6 and R_7 are the same or different groups. m, n: Integers of 1 or more ▲ Numerical formulas, chemical formulas, tables, etc. ▼ (III) R_8, R_9: A group selected from hydrogen, an alkyl group, a phenyl group, a benzyl group, or a derivative thereof, and R_
8, R_9 are the same or different groups. R_1_0: A group selected from a phenyl group, a benzyl group, or a derivative thereof. R_1_1: A group consisting of hydrogen, an alkyl group, or a group defined by R_1_0. n: An integer of 4 or more. (3) The polyester resin composition according to claim 1, characterized in that one or more inorganic substances selected from the group of talc, mica, kaolin, and silica are used as the inorganic compound having an average particle size of 50 μm or less. . (4) The polyester resin composition according to claim 1, wherein the metal salt of the carboxyl group is a sodium salt or potassium salt of the carboxyl group. (5) The polyester resin composition according to claim 1, wherein the compound having a metal salt of a carboxyl group is a compound having about 7 to 30 carbon atoms. (6) The polymer compound having a carboxyl group is a copolymer of olefin and (meth)acrylic acid or a copolymer of styrene and (
Claim 1, which is a copolymer of meth)acrylic acid
The polyester resin composition described in .