JPS612746A - Polyester resin composition - Google Patents

Abstract

PURPOSE:To provide the titled composition composed of polybutylene terephthalate, polyethylene (tere/isophthalate) and/or polyethylene isophthalate, a fibrous reinforcing material, and glass flakes, and having improved warpage. CONSTITUTION:(A) 100pts.(wt.) of a mixed polyester composed of (A1) 90- 20(wt)%, preferably 80-30% polybutylene terephthalate having intrinsic viscosity of 0.6-1.5 and (A2) 10-80%, preferably 20-70% polyethylene (tere/isophthalate) and/or polyethylene isophthalate wherein the amount of the isophthalate component is >3mol% based on the sum of the terephthalate component and the isophthalate component, is compounded and mixed with (B) 5-100pts., preferably 10-50pts. of a fibrous reinforcing material (e.g. glass fibers) and (C) 5-100pts., preferably 10-50pts. of glass flakes having aspect ratio of >=5.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a fiber-reinforced polyester resin composition that exhibits less warpage when formed into a molded product, and is used in automobiles, aircraft, ships, electric/electronic equipment, etc. industrial resin parts,
It is particularly suitable for use in high-strength, precision parts.

[Prior art]

■ Tokukai Akira! ;3-7/A// Polybutylene terephthalate 63~? q]i and the molar ratio of terephthalic acid/isophthalic acid is gs7is~/
jt/g! r polyethylene (tele/inphthalate)
This is an invention of a thermoplastic polyester resin composition consisting of 7 to 35% by weight, when reinforced with glass fiber, when the above polyethylene (tere/inphthalate) is not used, or when polyethylene terephthalate is used in its place. It is stated that there is less warping compared to the above.

■ JP-A-37-/DA-9330 Glass flakes S having an aspect ratio of S or more for 700 parts by weight of a copolyester resin with a halogen content of 3 to 2% by weight, which is obtained by copolymerizing a halogen-containing aromatic diol.
This invention describes a polyester resin composition containing up to 100 parts by weight, and it is described that when reinforced with a fibrous reinforcing agent, there is less warping than when glass flakes are not used.

[Problem that the invention seeks to solve]

The inventions (1) and (0) of the prior art described above relate to polyester resin compositions with less warpage, but when used for precision parts, they are still not fully satisfactory in terms of strength.

The present invention provides a polyester resin composition with improved warpage without impairing moldability or mechanical properties.

[Means to solve the problem]

■ Polybutylene terephthalate Polybutylene terephthalate used in the present invention is terephthalic acid or a dialkyl ester of terephthalic acid,
/ is a polyester resin obtained by polycondensation with terbutanediol.

The terephthalic acid constituting the above polybutylene terephthalate is partially composed of dibasic acids such as isophthalic acid, hexahydroterephthalic acid, diphenyldicarboxylic acid, adipic acid, and azelaic acid, or polybasic acids such as trimesic acid and trimellitic acid. May be replaced with a basic acid.

In addition, diols such as ethylene glycol, diethylene glycol, hexamethylene glycol, cyclohexane dimetatool, neopentyl glycol, bisphenol A, halogen-containing bisphenol A, or glycerin, pentaerythritol, which are part of the above /, +-butanediol, It may be replaced with a polyhydric alcohol such as

Intrinsic viscosity of polybutylene terephthalate (30 using a 7:1 mixed solvent of phenol and tetrachloroethane)
(measured at °C) is usually in the range of O0A~/.3.

(1)-7 Polyethylene (tere/isophthalate) This is produced by mixing terephthalic acid or its dialkyl ester and isophthalic acid or its dialkyl ester, and polycondensing the mixture with ethylene glycol.

The isophthalic acid component is preferably 3 mol % or more based on the total amount of the terephthalic acid component and the inphthalic acid component, and particularly preferably S to -0 mol %.

Part of the above ethylene glycol f'i, so, i, 3-
Propanediol, /l goobutanediol h'+6-
Diols such as hexanediol, neopentyl glycol, bisphenol A, halogen-containing bisphenol A, or polyhydric alcohols such as glycerin and pentaerythritol may be substituted.

What is the molar ratio of the isophthalic acid component in polyethylene (tele/isophthalate)? When a polyester is mixed with polybutylene terephthalate and polyethylene (tele/isophthalate) to form a mixed polyester, the mixture The isophthalic acid component of the polyester cannot be contained in the desired amount, and the effects of the present invention cannot be expected.

(1) Polyethylene isophthalate is produced by combining isophthalic acid or its dialkyl ester with ethylene glycol. Ethylene glycol is as above ■-/
As in, some parts can be replaced by other substances.

The polyester mixture used in the present invention is the polybutylene tele 7 tallate described in (1) above, and the polyester mixture described in (1) above.
-7 polyethylene (tele/isophthalate) and/
or a mixture of polyethylene isophthalate.

■Polybutylene terephthalate in the polyester mixture is 20 to 20% by weight, preferably Vig
o~30% by weight, ■-7 polyethylene (tere/isophthalate) and/or ■-u polyethylene isophthalate/Q~tro weight%, preferably 10~70
Weight%.

In this polyester mixture, it is preferable that the isophthalic acid component is 1 to 10 molti, particularly - to 6 molti based on the total amount of terephthalic acid component and isophthalic acid component in the mixture. As the fibrous reinforcing agent (■) Examples include glass fibers, carbon fibers, metal whiskers, etc., but examples include long diameters of 11 or more, lengths of 15μ or more, preferably S-0μ in diameter, pitch-based, acrylonitrile-based, cellulose-based, lignin-based, etc. Carbon fiber etc. are suitable.

The fibrous reinforcing agent is preferably used in an amount of 5 to 100 parts by weight, preferably 10-10 parts by weight, per 100 parts by weight of the polyester mixture. If the amount is too large, molding becomes difficult, which is not preferable.

The glass flakes (■) used in the present invention have an aspect ratio (ratio of major axis to thickness) of S or more.

Viio or higher is preferred. Specifically, the thickness is about 30μ, preferably Fi-1θμ, and the major axis is about 70μ-30μ, preferably about SOμ-10μ. If the aspect ratio is smaller than S, the effect of preventing warpage and improving the strength of the weld portion will be reduced. On the other hand, there is no problem in using one with a large aspect ratio, but
Since it will be crushed during blending with the resin, no effect can be expected from using a particularly large one.

The amount of glass flakes used is 100% of the polyester mixture.
5 to 100 parts by weight, preferably 10 to S
It is an O-heavy lid. If the amount is too small, the warpage prevention effect will be reduced.

On the other hand, if the amount is too large, molding becomes difficult, which is not preferable.

Further, up to half of the glass flakes can be replaced with glass beads.

Next, referring to the compounding means, the fiber reinforcing agent and glass flakes may be treated with an epoxy-based, epoxy-silane-based, or aminosilane-based surface treatment agent in order to improve adhesion to the resin.

In order to blend the fibrous reinforcing agent and glass flakes into a polyester mixture, the above raw materials may be mixed in any order.For example, the above raw materials may be mixed and melt kneaded, or a polyester mixture may be prepared and fibers A method of melting and kneading a mixture of a shape reinforcing agent and glass flakes.

A method using a fibrous reinforcing agent and/or a masterbatch of glass flakes can be adopted.

Other additives include aromatic halogen compounds, halogen-containing epoxy resins, halogen-containing polycarbonate resins, halogen-containing polyphenylene oxides, flame retardants such as halogen-containing polybenzyl acrylate, flame retardants such as antimony trioxide, and asbestos Combustion anti-dripping agents such as silica, alumina, silica alumina, silica magnesia, titania, calcium carbonate, talc, fillers such as gypsum, dyes and pigments, paraffins, fatty acid esters, fatty acid metal salts, bisamides A lubricant and other well-known additives may be used in combination. [Effects of the Invention] The composition of the present invention has excellent moldability and mechanical properties, and has small warpage, so it is of great value as an engineering plastic.

The composition of the present invention can be produced into three-dimensional molded products, various containers, films, etc. by various molding methods such as injection, extrusion, blowing, and compression.
It can be molded into various shapes such as sheets and tubes, and is suitable as a material for electrical, electronic parts, automobile parts, and other industrial uses.

〔Example〕

Hereinafter, the present invention will be specifically explained with reference to Examples, but the present invention is not limited to the following Examples unless the gist thereof is exceeded.

In the examples, "part" and "chi" indicate "part by weight" and "% by weight", respectively.

In addition, the tensile strength is ASTM D 63g and the bending strength is A.
Values measured according to STM D 790 are shown.

The moldability was measured at a resin temperature at which sufficient fluidity was obtained at a pressure of 60 kg/crd G when molding the above-mentioned test piece for strength measurement by injection molding.

The amount of warpage is 100111 mm in diameter when molded by injection molding.
g, the thickness of the 6th disk is drawn on a plane, and the sum of the height of the highest point of the raised peripheral part and the number of fins of the height of the peripheral part facing the center. Indicated.

Example 1 and Comparative Examples/~Co Intrinsic viscosity obtained by polycondensing polybutylene terephthalate with an intrinsic viscosity of o and gs, a mixture of dimethyl terephthalate and dimethyl inphthalate with a molar ratio of qo:lo, and ethylene glycol is 0.7! 10 parts of a polyester mixture tri-blended with polyethylene (tele/isophthalate) in the proportions shown in Table 1 below, and glass fibers shown in Table 1 below (manufactured by Asahi Fiberglass ■, MA<1/ ), glass flakes (Japanese plate crow ■H
, ccyyg) and Example-, glass peas (manufactured by Toshiba Ballotini H, EB7J/B) were mixed, and the mixture was melt-kneaded at 2 g and 3° C. using a vented extruder and extruded into pellets. .

This pellet was used in a 3.9 oz injection molding machine (Japan Steel Works, T#Jj, type N-7OOBIIv) and a mold for molding test pieces specified by ASTM and warpage test pieces of 100 m1 x /, 6 w. Molding was carried out at a mold temperature of 0.degree. C., an injection pressure of 60 Y/da, an injection time of 7 seconds, and a cooling time of 10 seconds.

The physical properties and moldability of the obtained molded article were as shown in Table 1 below.

For comparison, the case where glass flakes and glass beads were not used (Comparative Example/) and the case where polyethylene terephthalate (Tere/Isophthalate) with a degree of 0 and 0 was used alone (Comparative Example/) ) results are also listed.

Examples 5 to 7 A product obtained by polycondensing ethylene glycol with a mixture of dimethyl terephthalate and dimethyl iso-7 talate in a molar ratio of gs:7 g to (1) of the polyethylene (TEW isophthalate) used in Examples 7 to 7. Polyethylene (tele/isophthalate) with an intrinsic viscosity of 0.75 was used in the proportions shown in Table 2 below, and the other operations were carried out in the same manner as in Example 2, and the results shown in Table 2 below were obtained. I got it.

7/', / Example 1 and Comparative Examples 1 to 6 The same polybutylene terephthalate polyethylene (tere/isophthalate) used in Example 1 was added to 100 parts of a polyester mixture with an Aθ loss of 0, and 73 parts of glass fiber was added.
part, glass flakes - 0 parts, polybromophenylene oxide (manufactured by Crate Lakes, flame retardant PO-64IP)
) J, 5 parts and 3.5 parts of antimony trioxide,
lI.

Pellets of extruded S-flammable polyester resin composition were produced by melt-kneading at 3S° C. using a pent-type extruder.

This pellet was injection molded in the same manner as in Example 3, and the results shown in Table 3 below were obtained.

For comparison, when glass flakes were not used (
Comparative example 1), polyethylene (7″/inophthalate)
The results are also shown when there were few trays (Comparative Example S) and when polyethylene terephthalate was used alone in place of polyethylene (tere/isophthalate) (Comparative Example 6).

Claims (2)

[Claims] (1) (a) 90-20% by weight of polybutylene terephthalate; (b) polyethylene (tere/isophthalate) and/or
Or a polyester resin composition prepared by blending (c) 5 to 100 parts by weight of a fibrous reinforcing agent and (d) 5 to 100 parts by weight of glass flakes to 100 parts by weight of a polyester mixture consisting of 10 to 80% by weight of polyethylene isophthalate. thing. (2) Polyethylene (tele/isophthalate) whose isophthalic acid component is 3 mol% or more based on the total amount of terephthalic acid component and isophthalic acid component.
The polyester resin composition according to claim 1, wherein the polyester resin composition is a polyester resin composition (isophthalate).