JPS58176243A - Thermoplastic resin composition - Google Patents

Abstract

PURPOSE:To provide the titled resin compsn. which is suitable for use in the production of coin mechanism parts, little suffers lowering in mechanical properties during high-temperature processing and is short in weldline, by blending a stabilizing quantity of an arom. polyamide with a polyphenylene ether resin. CONSTITUTION:0.1-5pts.wt. arom. polyamine (B) is blended with 100pts.wt. polyphenylene ether resin (A) such as a homopolymer consisting of repeating units of formulas I and/or II (wherein R1, R2, R3, R4, R5, R6 are each a 1-4C alkyl excluding tert-butyl group, aryl, halogen, H) or a copolymer thereof to obtain the desired thermoplastic resin compsn. Examples of component B are p,p'- diaminodiphenylmethane, m-xylenediamine, diaminodiphenyl ether, o-tolidine, m-xylenediamine and m-diaminobenzene.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a polyphenylene ether-based 1M resin composition containing a stabilizing amount of aromatic polyamines, which exhibits less deterioration in mechanical properties during high-temperature processing and has a good appearance. be.

In recent years, polyphenylene ether resin compositions have been shown to have excellent mechanical properties such as moldability, dimensional stability, impact resistance, heat resistance, and rigidity, as well as excellent electrical properties, and can even provide flammability. Since then, it has been widely used in electrical parts, electronic parts, automobile parts, industrial parts, etc. -Recently, in order to save resources and reduce weight, parts themselves have become thinner or more complex, and on the other hand, hot runner systems are being used to increase efficiency in molding conditions, or resin If& to increase molding cycles. The recent trend is to increase the temperature to around 250 to 320°C. The commercial value of the material resin is that it not only shows little deterioration in mechanical properties under increasingly strict processing conditions, but also maintains good surface gloss for thin-walled and complex molded parts, and is suitable for complex molded parts such as multi-point gates. In electrical parts such as switches that require a large number of bosses, or coin mechanism parts for vending machines, it is desired that the weld-in period, which occurs when molten resin solidifies and occurs at the food interface, be short.

Regarding stabilizers for preventing heat aging for polyphenylene ether resin compositions, various technological developments have been made in the past9, such as USF 4,123,474 and JP-A-52-1999.
No. 84247 discloses a heat-aging composition with the addition of diphenylamines, and USP 3.956.423 discloses a heat-aging composition with the addition of N,N'-di-β-naphthyl-P-phenylenediamine. has been done.

The present inventors have diligently searched for a more practical stabilizer for polyphenylene ether resin compositions that exhibits less deterioration in mechanical properties during high-temperature processing, good surface gloss, and short weld lines. The present invention was achieved by discovering that aromatic polyamines, in particular, meet the above objectives.

The aromatic polyamines referred to in the present invention include p,p'-diaminodiphenylmethane, p,p'-
Examples include diaminodiphenylsulfone, diaminodiphenyl ether, 0-tolidine, m-xylene diamine, m-cyaminobenzene, ρ-diaminobenzene, p-xylene diamine, and the like. The aromatic polyamines C can be used alone or, if desired, in combination with two or more, to have a good improvement effect. The amount added is 0.1 to 5.0 per 100 parts by weight of polyphenylene ether resin.
Parts by weight are preferred. Outside this range, the appearance and physical properties will be unbalanced, which is undesirable.

The polyphenylene ether resin composition referred to in the present invention includes a polyphenylene ether resin, specifically a resin composition comprising a polyphenylene ether resin and a styrene resin, and a resin composition comprising a polyphenylene ether resin and a rubber-modified impact-resistant styrene resin. Any four of the resin compositions include a mixed resin composition consisting of a polyphenylene ether resin, a rubber-modified impact-resistant styrene resin, and a styrene resin.

In the present invention, polyphenylene ether resin (PPE
), a homopolymer or a copolymer having the general formula; % formula % as a repeating unit and the constitutional units consisting of CI) or [I] and [■] can be used.

A typical example of a PPH homopolymer is poly(2,6-
dimethyl-1.4-)unishin)ether, poly(2-
methyl-6-ethyl-1,4-phenylene) ether,
Poly(2,6-diethyl-1,4-phenylene) ether, poly(2-ethyl-6-n-propyl-1,4-phenylene) ether, poly(2,6-di-n-propyl-1)
,4-phenylene]ether, poly(2-methyl-6-
nbuf-1,4-phenylene)ether, poly(2-
Ethyl-6-itubrobyl-1,4-phenylene) ether, poly(2-methyl-6-chloro-1,4-phenylene) ether, Fo1J (2-71 thyl-6-hydroxyethyl-1,4-phenylene) Ether, poly(2-
Examples include homopolymers such as methyl-6-chloroethyl-1,4-phenylene) ether.

The polyphenylene ether copolymer has the general formula (where R
1, R4, R11R- have the same meanings as above. )
A bo IJ 7 include.

Furthermore, these polymers may be grafted with a monomer containing styrene as a product.

The styrene resin used in the present invention is a polymer consisting of 1s or two or more aromatic vinyl monomers represented by the general formula, and specifically, styrene, α-methylstyrene, vinyltoluene, vinyl Copolymerization with polymers such as ethylbenzene, vinyl xylene, tert-7” tylstyrene, chlorostyrene, etc. and/or vinyl compounds copolymerizable with these aromatic vinyl compounds, such as acrylonitrile, methyl methacrylate, methacrylonitrile, maleic anhydride, etc. Including coalescence.

In addition, rubber-modified impact-resistant styrenic resins include polybutadiene, butadiene-styrene copolymer, 7.2 di, 7
-□V7bu. one or more rubber phases such as phytadiene rubbers such as 7.2 diene-acrylonitrile copolymers, acrylic ester rubbers, ethylene-propylene rubbers, butyl rubbers, chlorobenzene rubbers, and natural rubbers; The resin phase component is a polymer derived from the above-mentioned aromatic vinyl monomer, and/or a copolymer with a vinyl compound that is copolymerizable with these aromatic vinyl compounds. Also included are polymers.

In addition, methods for producing styrenic resins and rubber-modified impact-resistant styrenic resins are available in the art [11]. .

Next, weld lines that occur at the solidified interface between molten resin can be a problem in products molded with complex molds, such as switches with multi-point gates that require many bosses, or coin mechanisms in vending machines. is an important characteristic along with surface gloss in determining commercial value, but the inventors of the present invention have carefully studied the evaluation method and decided to use a test piece that inevitably has weld lines as shown below. This made it possible to determine the length of the weld line with good reproducibility. In other words, as shown in the drawing, vertical 1
55I 1551 horizontally and 2-thick flat plate 1 on the center line, 3 vertically at 2.551 from the upper side, 4 horizontally flat plate with window 2, 1.5 eIIl directly above $2, upper side From 161
A bin gate 3 of 2 mφ is installed at the location to create a flat plate. The resin melted and pressurized by the injection molding machine passes through the 2-φ bin gate 3, passes around the window 2, and inevitably welds at the solidified interface between the resins just opposite the bin gate 3 of the window 2. Line 4 occurs. By measuring the length of this weld line 4, it has become possible to easily and reproducibly grasp the correlation with the weld line of actual complex molded products such as switches and coin mechanisms of vending machines. The present inventors have studied and found that in order to satisfy the above-mentioned practical requirements, the weld line measured by the above measurement method must be 40 cm or less.

The polyphenylene ether resin composition containing a stabilizing amount of aromatic polyamines as used in the present invention can be obtained by mixing a stabilizing amount of aromatic polyamines and a polyphenylene ether resin, using a Banbury mixer, a roll, a kneader, etc. -1
It is obtained by melt-kneading using an extruder or the like. IP! l to
The characteristics of the present invention are not limited by the melt crosstalk method. If desired, other additives may be added, such as plasticizers, ultraviolet absorbers, flame retardants, colorants, and fibrous reinforcing agents such as glass fibers and carbon fibers, as well as fillers such as glass peas, calcium carbonate, and talc. agents may be added. As plasticizers, polybutene, low molecular weight polyethylene, mineral oil, epoxidized soybean oil, polyethylene glycol, and fatty acid esters are particularly good.As flame retardants, aromatic phosphate esters, red phosphorus, aromatic halogen compounds, and Antimony oxide and the like are particularly effective.

In addition, it is also possible to use it in combination with other stabilizers; for example, phosphorous esters, phenols, dithiocarbamate metal salts, inorganic sulfides, and metal oxides can be used alone or in combination. .

Examples are shown below, but it goes without saying that the present invention is not limited to the following examples.

Example 1 Intrinsic viscosity [η] is 0.65 (30°C in chloroform)
Poly(2,6-dimethyl-1,4-phenylene)
70 parts by weight of ether and TOBOLEX 860 (manufactured by Mitsui Toatsu Chemicals) 30 as a rubber-modified impact-resistant styrene resin.
parts by weight and 7), p'-diaminodiphenylmethane 4
．． 0 parts by weight, cresyl phenylphosphny) and 0.5 parts by weight of Sumilizer BBM (manufactured by Sumitomo Chemical) were blended and granulated by extrusion with a twin-screw vent, and the resulting pellets were heated at 310°C. Test pieces were obtained by injection molding and their physical properties were investigated. The results are shown in Table 1.

Example 2 44 parts by weight of poly(2,6-dimethyl-1°4-phenylene) ether used in Example 1, 50 parts by weight of Stylon 492 (manufactured by Asahi Dow) as a rubber-modified impact-resistant styrenic resin, and styrene-based As a resin, 6 parts by weight of Stylon 685 (manufactured by Asahi Dow) and p.

The mixture was blended with 0.6 parts by weight of P'-diaminodiphenylmethane and granulated using a twin-screw vented extruder, and the resulting pellets were injection molded at 290°C to obtain test pieces and their physical properties were examined. The results are shown in Table 1.

Example 3 Using the same method as in Example 2, 0.6 parts by weight of p=p'-diaminodiphenylmethane was added to 0.6 parts by weight of m-xylene diamine.
．． Pellets were obtained using exactly the same formulation as in Example 2 except that the amount was changed to 6 parts by weight, and the physical properties of the pellets were investigated and the results are shown in Tables 1 & C.

Example 4 The same method as in Example 1 was used, except that only 4.0 parts by weight of p=p'-diaminodiphenylmethane was changed to 4.0 parts by weight of P-diaminobenzene, and the formulation was exactly the same as in Example 1. Table 1 shows the results of examining the physical properties of the pellets obtained.

Example 5 Intrinsic viscosity [η] is 0.63 (30°C in chloroform)
Poly(2,6-dimethyl-1,4-phenylene)
20 parts by weight of Styron 685 (manufactured by Asahi Dow), 5.0 parts by weight of p'-diaminodiphenylmethane, 0 parts by weight of cresylfer phosphate i, 0 parts by weight of cresylfer phosphate i, and biaxial venting. The pellets were granulated using an extruder, and the resulting pellets were injection molded at 320°C to obtain test pieces and their physical properties were examined. The resulting specimen was completely transparent. The results are shown in Table 1.

Example 6 In exactly the same manner as in Example 1, the temperature and intrinsic viscosity [η) were 0.
．． Poly(2,6) which is 65 (30'C in chloroform)
-dimethyl-1,4-phenylene) ether, the intrinsic viscosity [η] was 0.68 (3 parts by weight in chloroform).
Example 1 except that 70 parts by weight of a copolymer of 2+6-dimethylphenol (90 mol%) and 2.3.6-dolimethylphenol (10 mol), which was 0°C), was used. Granulation was performed with exactly the same composition, and the results of the physical properties are shown in Table IK.

Comparative example 1 Using exactly the same method as in Example 1, P.

Except for not adding P′-diaminodiphenylmethane,
Pellets were obtained using exactly the same formulation as in Example 1, and their physical properties are shown in Table 1.゛Comparison IP12 Using exactly the same method as in Example 5, P.

Pellets were obtained in exactly the same manner as in Example 5, except that 5.0 parts by weight of diphenylamine was added instead of 5.011 parts of p'-diaminodiphenylmethane. The obtained test piece had uneven surfaces and was slightly opaque.

Its physical properties are shown in Table 1.

Comparative example 3 Using exactly the same method as in Run-15, p.

Pellets were prepared in exactly the same manner as in Example 5, except that 5.0 parts by weight of N,N'-di-β-naphthyl-P-phenylenediamine was added instead of 5.0 parts by weight of P'-diaminodiphenylmethane. Obtained. The obtained test piece had uneven surfaces and was slightly opaque. Its physical properties are shown in Table 1.

1) Gloss: Using a dumbbell test piece according to ASTM D638rc, using a gloss meter manufactured by Suga Test Instruments, at an incident angle of 60°
Measure the dead end and gate end.

2) Izot impact strength: ASTM D2563)
Heat distortion temperature: ASTM D64 & 4] Melt flow rate: Measured at 250℃ using a Zen Kogyo melt flow indexer with a # load of 10.

[Brief explanation of the drawing]

The drawing is a plan view of a resin flat plate created for weld line evaluation. 4...Weldline agent Masao Miyake (and 1 other person)

Claims (1)

[Scope of Claims] 1. A polyphenylene ether resin composition containing a stabilizing amount of aromatic polyamines. 2. The resin composition according to claim 1, wherein the aromatic polyamine is p,p'-diaminodiphenylmethane. & The resin composition according to claim 1, wherein the aromatic polyamine is m-xylene diamine. 4. The resin composition according to claim 1, wherein the aromatic polyamine is diaminodiphenyl ether.