JPS59109552A - Polyester resin composition - Google Patents

Abstract

PURPOSE:To provide the titled compsn. having excellent strength, heat resistance, dimensional stability, mold release characteristics and biteability, by blending glass fiber, talc and glass foil with polyethylene terephthalate and further externally adding a specified ester compd. thereto. CONSTITUTION:5-9wt% glass fiber (A), 15-40wt% talc (B) and 0-5wt% glass foil (C) are blended with polyethylene terephthalate in such a proportion that the combined quantity of components A, B and C accounts for 20-50wt% of the quantity of the compsn. 0.01-2wt% ester compd. derived from a satd. aliph. monocarboxylic acid and a neopentyl polyol of formula I (wherein R1-R4 are each H or a fatty acid ester group of formula II ; n is 10-30) is externally added to the resulting reinforced resin compsn. An example of the ester compd. of formula I is neopentyl polyol tetrastearate.

Description

[Detailed description of the invention] The present invention relates to polyester resin compositions.

More specifically, the present invention relates to a polyester resin composition that has excellent dimensional stability, mold release properties, and biting properties.

Polyethylene terephthalate has a slow crystallization rate, so the in-situ crystallization by ordinary molding methods is low, and a major drawback is that only products with poor physical properties and moldability can be obtained. In order to improve this point, methods are known such as adding an inorganic filler such as glass fiber, adding a crystal nucleating agent 710, or molding with a cylinder temperature mold to increase the degree of crystallinity.

However, when a fibrous filler metal such as glass fiber is used alone, anisotropy in physical properties such as strength and shrinkage rate of the molded product becomes large, which poses a practical problem. In this respect, if a so-called powder filler having no fiber length is blended, the anisotropy of the molded product will be reduced, but the strength and heat resistance will be low, and no practical reinforcing effect can be expected. Accordingly, although various methods have been proposed for using fibrous fillers and powdered fillers in combination, it is difficult to maintain a balance between reinforcing effect and anisotropy. ? If: 4 is difficult, and a fully satisfactory result has not been obtained.

Furthermore, it is extremely important from the economical point of view to shorten the time required to take out the molded product from the mold, that is, the entire molding cycle. Therefore, the reality is that molding is usually done by shortening the injection time and cooling time as much as possible. However, although the cooling time strongly depends on the size and thickness of the molded product, in reality it is more strongly dependent on the time during which the chips are weighed, the so-called bite time. Therefore, if it is possible to shorten the time required for biting, the molding cycle can be expected to be shortened.

In view of the above-mentioned current situation, the present inventors have conducted extensive tests to obtain a polyester resin composition that has a high reinforcing effect, high heat resistance, excellent dimensional stability, and can shorten the biting time. By creating a polyester composition containing Merck and Karas foil in a specific range, and further adding a specific amount of temporary esterification additives to this composition, we achieved all of the objectives of the 1'9R period. As a result, we have arrived at the present invention.

That is, in the present invention, the production amount of glass fiber is 5 to 9%, the talc is 15 to 40% by weight, and the glass foil is 0 to 5% by weight, and the total amount of these fillers is 20% by weight based on polyethylene terephthalate.
~50! Strengthened flank composition by distributing ji%? ! IK is a polyester resin composition in which at least one layer of an esterified adduct represented by the following general formula (I) is externally added in an amount of 0.01 to 2% by weight.

1 H2 R4-o-aH2-c -an2-0-R@・-・φ・
...(1) H2 Tatami 〇3 In the formula, R1 to R4 are hydrogen or an aliphatic ester group represented by 0nH2n+100 (" is 10 to 50). However, R1 to R4 are not all hydrogen.

In the polyester resin composition WII/c of the present invention, the glass fiber is used to improve the reinforcing properties and heat resistance of the molded product, but if the amount distributed is low, the strength and heat resistance level of the molded product will be affected. is so low that it is impossible to obtain a product that can be put to practical use. Therefore, in order to compensate for this point (it is possible to achieve the same reinforcing effect by using a powdered filler with less anisotropy), the powdered filler is usually used as a bulking material, such as a filler. No effect on gender can be expected.

In particular, regarding heat resistance, the fiber length of the filler is the dominant factor, and even if a large amount of powdered filler is blended, almost no improvement in heat resistance is observed. However, some inorganic metal compounds known as crystal nucleating agents for polyethylene terephthalate are extremely hot metals, but chemical compounds commonly used as nucleating agents are not suitable for use as nucleating agents. IIe? Since it has a deteriorating effect, it is not possible to incorporate it in large amounts, and it is also inappropriate from the point of view of reinforcing properties.

7. J) Core V In the present invention, the reason is clear, but the instep of the IJ terminal optical filler is used in combination with Merck all glass fiber in the above distribution.
In addition to shouldering the remarkable young fruit that makes this ditto, even if it is given a large amount, the 3 degree drop does not occur, but rather 'MiIJj ditto,
Moreover, it not only has an excellent fc specific effect of improving anisotropy, but also further improves the glass foil blending vc strength and heat resistance. In general, the metal penetration properties are significantly improved compared to those of the above-mentioned externally added esterified additives.

The polyethylene terephthalate used in the VC of the present invention is a linear polyethylene terephthalate homopolymer having ethylene terephthalate units as a constituent unit, and other polyhydric alcohols, aromatic dicarboxylic acids, aliphatic dicarboxylic acids, etc. A copolymer obtained by copolymerizing a small amount of a copolymer or a mixture thereof, or a mixture thereof, may be mixed with other thermoplastic resins, etc., so that the homopolymer or copolymer is the main component.

Further, the glass fiber used in the VC of the present invention is a glass roving or a glass chopped strand having an aspect ratio of 201 or more, and is not preferably eb9 or a powdered milled fiber. The content of glass fibers in the reinforced resin composition is preferably in the range of 5 to 9 weight percent. If the amount is less than 5% by weight, the reinforcing properties and especially the vc 1 phase thermal properties of the molded product tend to deteriorate. Generally, as the glass fiber content increases, the anisotropy of the strength and shrinkage rate of the molded product increases, and when the amount exceeds 9% by weight, the anisotropy increases rapidly. In addition, the strength of the molded product in the direction parallel to the flow direction of the resin during molding increases with the increase in the number of glass fibers, but in the direction perpendicular to it
When the glass fiber content exceeds 9% by weight, the strength tends to be lower than that of unreinforced polyethylene terephthalate 1.

Furthermore, the talc used in the present invention has an average particle size of 0.01 to 10 μm from the viewpoint of heat resistance of molded products.
Powdered ones are preferred.

In addition, the reinforcing value is 15 to 40 in terms of heat resistance and anisotropy improvement effect.
厘m% is a good value.

Furthermore, the glass article in the present invention has an average particle size of 500
It is in the form of flakes of μ to -F.

The content of the glass foil in the reinforced resin composition is 5 weight coefficients, and by adding the glass foil, the strength and heat resistance of the molded product can be further increased by 1 m. This glass Y6
If the content exceeds 5% by weight, it is not preferable because the workability when molding the composition decreases.

In addition, the above polyethylene terephthalate in the present invention,
It is preferable that the total amount of glass fibers, Merck and glass foil in the reinforced resin composition composed of glass fibers, Merck and glass foil is 20 to 50% by weight, and 20 weight Ji + 1: Chi If the amount is less than
In particular, the heat resistance decreases significantly. In addition, if the amount exceeds 50 cm, the workability during molding and the appearance of the molded product will be poor.

The polyester resin composition of the present invention is obtained by externally adding at least 0.01 to 2 amounts of -S gold of the ester compound represented by the general formula (R) to a reinforced resin composition containing the above-mentioned fillers. Here, the ester compound represented by the general formula (I) ?'' is an ester compound of neopentyl polyol and a saturated IJm aliphatic monocarboxylic acid having a chain length of 10 to 30 carbon atoms. Examples of the aliphatic monocarboxylic acids include phosphoric acid, myristic acid, valmitic acid, stearic acid, aragic acid, cerotic acid, melisin, n-hentylcontanic acid, etc.Esters The compound has the general formula (1)
In the present invention, this esterified adduct is used alone, and the parent is mixed to form a product in the above range. If the external nitrification amount is less than 0, L]1 weight, the biting property will not improve. Also 2ffi
If the amount of external addition exceeds ii%, the penetration property is rather inferior to that of a composition without the ester compound added thereto. Also, regarding the method of adding montan wax ester to the above polyethylene terephthalate, glass fiber, Merck type, etc., if the three or four components of glass foil are added all at once, little improvement in penetration property can be expected. .

An example of the complete preparation of the polyester resin composition of the present invention is to add a predetermined amount of glass fiber, Merck and, if necessary, glass foil to sufficiently dried polyethylene terephthalate, and mix in a suitable mixer such as a tumbler. After fC, it is fed to an extruder or the like and subjected to melt cross-extrusion to form pellets.

The esterified adducts are added to the vc before the pellet is cooled.
It may be added or may be coated with pellet VC immediately before injection molding or extrusion molding.

The polyester resin composition of the present invention may contain various stabilizers such as ultraviolet absorbers, antioxidants, and heat deterioration inhibitors, dyes and pigments, nucleating agents, flame retardants, and quenching agents without departing from the purpose of the present invention. All additives can be blended 1. The invention will be specifically explained below with reference to Examples.

Examples 1 to 26, Comparative Examples 1 to 9 Polyethylene terephthalate having an intrinsic viscosity of 0.71 as measured at 25°C in a mixed solvent of equal amounts of ethane and phenol, chopped strands of IC3+m, with an average of 5μ Glass foil with an average diameter of 550 μm was added in the proportions shown in Tables 1 to 6, mixed for 5 minutes in a tumbler, and then mixed with a 40 mm diameter extruder with L/D = 25.
The pellets were extruded at 0''C. Specified amounts of various additives shown in Tables 1 to 5 VC were externally added to each of these pellets.
A pellet for molding was obtained.

The above molding pellets were dried with hot air at 150"C for 12 hours, and then molded in a 50+mnφ, 5 oz screw in-line injection molding machine at a cylinder temperature of zs.

°C1 Injection molded at a mold temperature of 80°C, 6.4mm thick specimen for measuring thermal distortion temperature (nIJT), '5.2 thickness curve is a test specimen 110WIX 110111+llX 5
A 1+1111 flat plate was prepared and its physical properties were evaluated. H,lJ
T was measured using a Ml)T specimen according to AI:lTMi) 648, and the strength of the curve was measured according to ABTMD 790 IC. Warpage was measured using a flat plate of 110 mm x 110 pieces x 5 spaces.

The biting property and mold releasability were measured by the method shown below as fC.

Biting property After drying the above molding pellet with hot air at 15[1"C for 4 hours, it was immediately molded using a VCS ounce injection molding machine with a cylinder temperature of 280°C, a mold temperature of 80°C, and a cooling time of 50 seconds. ASTMI dumbbell, HDT specimen, and Izotsu impact specimen can be taken at the same time.A molded product (weight 68t) fMeasure the biting time (plasticization time) when molding.The shorter the biting time, the better the biting property. .

Mold releasability Immediately after drying the above molding pellets with hot air at 150C for 4 hours, the cylinder temperature was 28°C using an IC 8oz injection molding machine.
A box-shaped molded product (external dimensions: length: 100 x 4: yellow: 120 g x height: 40 pieces) was completely molded under the following molding conditions: 0°C, mold temperature: 140°C, cooling time: 50 seconds. In addition, a pressure sensor (strain gauge) was installed between the extrusion plate and the extrusion hinge in the mold used in this experiment. (referred to as a value) can be detected by a photographic device.

The mold release property is excellent due to the low ejection resistance value.

Table 1 (Examples 1 to 15) Strength and heat resistance obtained by using glass fiber and talc purple in combination
6 VC is excellent, and by externally cutting neopentyl glycol tetrastearate, the biting property and mold release property are greatly improved by rjJvc.

As is clear from Table 2 (Examples 14 to 26), the fatty acid esters of various neopentyl polyols exhibit excellent biting properties and mold release properties.

As is clear from Table 5 (Comparative Examples 1 to 9), the yarns that were not coated with Merck had large warpage and poor heat resistance. Furthermore, the biting and mold release properties cannot be improved by externally adding other fillers to IC alone. The father is the ester compound? When kneaded into chips, V has no effect on biting properties.

Claims (1)

[Claims] Polyethylene terephthalate V size glass fiber 5~
9 wounds 0, talc 15-4ozm% and crows 0-5
% by weight, and the total amount of these fillers is 20-50x'
jt% of the reinforced resin composition containing the general formula (I)
At least one esterified product represented by 0.01
~2wt% external addition 7Jl]-,! Polyester resin composition wJ. R CH2 R4-0-C! H2-0-CH2-0-R2...
...(I) CH2 3 In the formula, R1 to R4 are hydrogen or 0nH2n+1, C0(n
is a fatty acid ester group represented by 10 to 60). However, R and -R4 are not all hydrogen.