JPS64991B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a composition comprising a polyarylene sulfide resin and a polyethylene terephthalate resin. Polyarylene sulfide resin and polyethylene terephthalate resin have excellent heat resistance and chemical resistance, and are used as engineering plastics for various purposes. However, each resin needs to be improved in order to be used in a wider range of applications. That is, polyarylene sulfide resin has a drawback that it cannot be used in applications where impact resistance is important because it has low elongation and is brittle. Regarding this point, impact resistance can be improved by reinforcing the polyarylene sulfide resin with glass fiber, but this is still not sufficient. In addition, polyarylene sulfide resin has a high degree of brown coloration, and if you want to apply various colors depending on the application, a large amount of white filler is required, which reduces the mechanical strength of polyarylene sulfide resin. The results are as follows. Another point that limits the expansion of the uses of polyarylene sulfide resins is the price. Fillers are added to reduce prices, but there is a limit to the amount of fibrous reinforcing materials such as glass fiber that can be added, and other fillers result in a significant decrease in mechanical strength. What is particularly important to know is that although the apparent price is reduced by such a filler combination, the reduction in the volumetric cost, which is the real price, is small. On the other hand, although polyethylene terephthalate resin alone is used in large quantities for fibers, monofilaments, sheets, and films, it has poor mold release properties at mold temperatures of 70 to 130°C in injection molding, and this is because it is reinforced with glass fiber. The same is true even if Furthermore, since polyethylene terephthalate resin is an ester type polymer, it is easily hydrolyzed and cannot be used for parts that come into contact with hot water or steam. In addition, polyethylene terephthalate resin has a low heat distortion temperature, and a high heat distortion temperature can only be achieved by reinforcing it with glass fiber.
Long-term heat resistance cannot be said to be sufficient. Conventionally, a blend of polyarylene sulfide resin and polyethylene terephthalate resin had a large decrease in mechanical strength compared to each resin and was not commercially noteworthy, but according to the present invention, the mechanical strength Not only does it not cause any deterioration, it also improves the elongation of the polyarylene sulfide resin and increases its impact resistance.Furthermore, the brown coloring is reduced, making it easier to apply various colors, and at the same time, it is inexpensive. It has been found. Furthermore, it has been revealed that the present invention not only improves the mechanical properties and mold release properties of polyethylene terephthalate resin during injection molding, but also improves its hydrolysis resistance and heat resistance. That is, the present invention comprises 2 to 95 parts by weight of a polyarylene sulfide resin and 98 to 5 parts by weight of a polyethylene terephthalate resin, and the polyarylene sulfide resin does not substantially have a thermally crosslinked structure. or even if it has ASTM
Melt flow rate defined by D1238-70T is 300
℃, 15 or more under a load of 2160g, and the polyethylene terephthalate resin has an intrinsic viscosity of 0.4 to 2.0.
The present invention relates to a resin composition characterized by having the following. The polyarylene sulfide resin of the present invention is
For example, it can be obtained by reacting a polyhaloaromatic compound with an alkali metal sulfide in a polar solvent. The typical structure is

[Formula]

Even if it contains a unit represented by the formula (where X is O, SO ₂ , SO, C(CH ₃ ) ₂ , R ₁ , R ₂ , R ₃ , R ₄ is a hydrogen atom or an alkyl group), good. A typical example of polyarylene sulfide resin is polyphenylene sulfide resin, which is offered on the market as a product called "Ryton" by Phillips Petroleum, which was previously used for injection molding. is "Ryton P-4" or "Ryton R-6", which are made by heating and crosslinking low molecular weight polyphenylene sulfide resins obtained by polymerization below the melting point (285°C). Melt viscosity is 0.5~ at 300℃ and 2160g load
Melt flow rate of 15 (ASTM D1238−70T)
have. In the present invention, it is necessary that the polyarylene sulfide resin has substantially no thermal crosslinking structure, or even if it does have it, it is not highly developed. The compatibility with the resin can be increased, and a polymer alloy with excellent properties without phase separation can be obtained. That is, such a polyarylene sulfide resin can be obtained, for example, by the method disclosed in JP-A-50-84698. Since the polyarylene sulfide resin obtained by such a method becomes a high molecular weight product through polymerization, there is no need for thermal crosslinking unlike conventional polyarylene sulfide resins. In the present invention, polyarylene sulfide resins that do not have a thermally crosslinked structure are particularly preferred; A polyarylene sulfide resin having only a crosslinked structure having -70T) is preferable. Such polyarylene sulfide resins also include those obtained by thermally crosslinking a low molecular weight product obtained by the method disclosed in Japanese Patent Publication No. 45-3368 at a temperature below or above the melting point of the polymer to form a high molecular weight product. It will be done. Alternatively, the desired high molecular weight product may be obtained by completing the polymerization before forming a high molecular weight product by the method disclosed in JP-A No. 50-84698, and then heating at a temperature below or above the melting point of the polymer. In any case, by selecting the heating temperature and time for the thermal crosslinking, a polyarylene sulfide resin having a desired melt flow rate can be obtained. If the melt flow rate of the polyarylene sulfide resin is 15 or less, it is not preferable because it becomes a highly crosslinked structure, resulting in poor compatibility with the polyethylene terephthalate resin and poor physical properties. The melt flow rate is particularly preferably 18 or more. The polyethylene terephthalate resin in the present invention is obtained by a melt or solid phase polymerization reaction of terephthalic acid or dimethyl terephthalate and ethylene glycol or ethylene oxide, and has an intrinsic viscosity of 0.4 or more and 2.0 or less.
If the intrinsic viscosity exceeds 2.0, it becomes difficult to be compatible with the polyarylene sulfide resin, and the mechanical properties deteriorate. Further, if the intrinsic viscosity is less than 0.4, the excellent eyelash properties of the polyethylene terephthalate resin will be lost, which is not preferable. A copolymer within a range that does not lose the properties of the polyethylene terephthalate resin may be used. Blending of the polyarylene sulfide resin and polyethylene terephthalate resin in the present invention can be carried out at 260 to 400°C using a single screw or twin screw extruder, preferably at 280 to 360°C. The blending amount of the polyarylene sulfide resin and the polyethylene terephthalate resin is 2 to 95 parts by weight, preferably 5 to 90 parts by weight of the polyarylene sulfide resin and 98 to 5 parts by weight, preferably 95 to 10 parts by weight of the polyethylene terephthalate resin. If the amount of polyarylene sulfide resin is less than 2 parts by weight and the amount of polyethylene terephthalate is less than 5 parts by weight, the blending effect will be substantially lost. The composition of the present invention includes fibrous reinforcing agents such as glass fiber, carbon fiber, potassium titanate, asbestos, silicon carbide, ceramic fiber, metal fiber, silicon nitride, and barium sulfate, calcium sulfate, kaolin, clay, pyrofluorite, bentonite. ,
Sericite, zeolite, mica, mica, nephelinsinite, talc, attalpargite, wollastonite, PMF, ferrite, calcium silicate, calcium carbonate, magnesium carbonate, dolomite, antimony trioxide, zinc oxide, titanium oxide , magnesium oxide, iron oxide, molybdenum disulfide, graphite, gypsum, glass beads, glass balloons and other inorganic fillers in the composition by 0.1 to 70% by weight.
It is possible to contain up to When adding these reinforcing agents or fillers, known silane coupling agents can be used. In the composition of the present invention, it is preferable to add a polyfunctional compound such as an epoxy resin, an acid anhydride, and an isocyanate in an amount of 0.1 to 10% by weight based on the resin component. Epoxy resins are particularly preferred because they can improve mechanical properties, and various known epoxy resins such as bisphenol epoxy resins, alicyclic epoxy resins, and novolak epoxy resins can be used. The composition of polyarylene sulfide resin and polyethylene terephthalate resin of the present invention can be used not only for injection molding and compression molding, but also for extrusion molding, blow molding, and foam molding, and can be processed into films, sheets, monofilaments, and fibers. can do. Further, after the molding process, heat resistance can be further improved by heating at 200 to 300°C under vacuum or in the presence of oxygen gas. Additives such as a mold release agent, a lubricant, a colorant, a heat stabilizer, an ultraviolet absorber, a foaming agent, and a rust preventive can be added to the composition of the present invention. Next, the present invention will be explained in detail with reference to Examples.
Note that % and parts in the examples are based on weight. Reference example 1 984g of sodium sulfide (60% purity), 47g of sodium hydroxide, and 765g of lithium acetate dihydrate
Paradichlorobenzene 1113 was added to 3080g of methylpyrrolidone and heated to 205℃ while dehydrating.
g, 1,2,4-trichlorobenzene 1.13 g, N
- 510 g of methylpyrrolidone was added, heated at 260°C for 5 hours, cooled, washed with water and dried. The obtained polyphenin sulfide has a melt flow rate (300
℃, 2160g load) was 25. This is called Polymer A. Reference Example 2 Polyphenylene sulfide obtained by polymerizing in the same manner as in Reference Example 1 without adding lithium acetate dihydrate was melt flow rate (300℃, 2160g load).
Showed 1840. The polymer was heated in air at 270°C for 3
The melt flow rate after thermal crosslinking for 4 hours, 5 hours, and 6 hours was 50 (Polymer B), respectively.
17 (Polymer C), 8 (Polymer D), and 2 (Polymer E). Example 1 The polyphenylene sulfide resin (polymer A) obtained in Reference Example 1 and the polyethylene terephthalate resin having an intrinsic viscosity of 1.03 were melt-kneaded at 310°C in a twin-screw extruder. A test piece obtained by injection molding the pellets obtained at 310°C (mold temperature: 130°C) showed no phase separation even after the test, and exhibited the physical properties shown in Table 1. An alloy of polyphenylene sulfide resin and polyethylene terephthalate resin has improved elongation and impact resistance compared to polyarylene sulfide resin, and has increased mechanical strength and heat distortion temperature compared to polyethylene terephthalate resin. .

[Table] Example 2 50 parts of the polyphenylene sulfide resin (Polymer B to E) obtained in Reference Example 2 and 50 parts of a polyethylene terephthalate resin with an intrinsic viscosity of 0.65 were melt-kneaded at 310°C in a twin-screw extruder. . The results shown in Table 2 were obtained for test pieces obtained by injection molding the obtained pellets at 310°C (mold temperature: 120°C).

[Table] (Note) Nos. 7 and 8 are of the present invention, and the others are for comparison.
Polyphenylene sulfide resin (polymer B) obtained in Reference Example 2 and polyethylene terephthalate resin with an intrinsic viscosity of 1.2 (1% talc as a nucleating agent)
6 mm long glass fiber for 70 parts of the mixture (containing)
30 parts and epoxy resin (Dainippon Ink Chemical Industry Co., Ltd.
0 to 2 parts of Epiclon 1050 (manufactured by Co., Ltd.) were added, and the mixture was melt-kneaded at 300°C using a twin-screw extruder. The results shown in Table 3 were obtained for test pieces obtained by injection molding the obtained pellets at 320°C (mold temperature: 100°C).

【table】

Claims (1)

[Claims] 1 Polyarylene sulfide resin 2 to 95
parts by weight and 98 to 5 parts by weight of a polyethylene terephthalate resin, and even if the polyarylene sulfide resin has substantially no thermally crosslinked structure or has a thermally crosslinked structure, it still meets ASTM D1238-70T.
A resin composition having a melt flow rate of 15 or more at 300° C. and a load of 2160 g as defined by the polyethylene terephthalate resin and having an intrinsic viscosity of 0.4 to 2.0.