JPS61204263A - Thermoplastic resin composition having excellent oil-resistance and heat-resistance - Google Patents

Abstract

PURPOSE:To obtain the titled composition having improved oil-resistance, by compounding an aromatic polyether resin, a copolymer of a styrene compound and an alpha,beta-unsaturated carboxylic acid (anhydride) and a polyamide resin having a crystal melting point of falling within a specific range. CONSTITUTION:(A) 5-50pts.wt. of an aromatic polyether resin, e.g. poly(2,6- dimethyl-1,4-phenylene) ether, etc., is compounded with (B) 3-25pts. of a copolymer containing preferably 60-99wt% styrene compound and preferably 1-40% alpha,beta-unsaturated carboxylic acid (anhydride), preferably styrene-maleic anhydride copolymer, styrene-maleic anhydride-methacrylate copolymer, etc. and (C) 35-80pts. of a polyamide having a crystal melting point of 265-320 deg.C (preferably nylon 46), and the mixture is preferably added with (D) 5-150pts. of a fibrous, flaky or powdery reinforcing agent (preferably glass fiber).

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a highly heat-resistant thermoplastic resin composition with excellent oil resistance. More specifically, it is a thermoplastic resin with improved oil resistance (solvent resistance) while taking advantage of aromatic polyether resin's excellent heat resistance, mechanical properties, electrical properties, and dimensional stability. Regarding the composition.

[Prior Art] In recent years, with the development of the electronics industry, the number of cases in which plastic molded parts such as connectors are attached to printed wiring boards has increased dramatically, and the need for plastics suitable for this type of use has also increased. It's increasing. In general, plastic parts used on printed circuit boards require a high degree of dimensional accuracy, electrical properties, rigidity, etc., as well as heat resistance to withstand soldering, and resistance to cleaning with Freon, halogen, and other solvents required after soldering. Must have solvent resistance. In particular, in recent years, higher solder heat resistance has been required in many cases due to demands for smaller parts, higher packaging density, faster processing speeds, etc.

For example, in conventional soldering process, soldering was done on the back side of the printed circuit board where the pins were inserted, so the plastic molded product itself was not directly heated to the soldering temperature, but recently, cream solder etc. A so-called rift soldering method has been proposed, in which the parts are attached in advance, and then the whole part is placed in a high-temperature furnace and the solder is melted and attached. In this case, the plastic molded product itself will be exposed to temperatures exceeding 260° C. for several tens of seconds, and an extremely high degree of heat resistance will be required.

Furthermore, in order to increase the cleaning efficiency in the subsequent solvent cleaning process, it is becoming mainstream to perform soldering in a high temperature black air state, and the requirements regarding solvent resistance are also becoming higher.

For these reasons, plastics such as polycarbonate and polybutylene terephthalate, which have traditionally been commonly used for this type of application, cannot meet the requirements, and plastic materials such as polyphenylene sulfide, polyether sulfone, and polyether ether kedone are being used. It is attracting attention as a product that satisfies demand. However, all of these materials are extremely expensive and are said to be difficult to use for general purposes, so there is a need for cheaper and better quality plastic materials.

Incidentally, aromatic polyether resins are known as resins with excellent heat resistance. This aromatic polyether resin has excellent mechanical properties, electrical properties, and heat resistance, as well as good dimensional stability, so it is attracting attention as a resin suitable for a wide range of applications. However, its disadvantage is that it has poor solvent resistance, and it also does not have enough heat resistance to be soldered. It is also well known that there are problems with moldability.

Various studies have been conducted to improve the drawbacks of polyether resins. For example, in Japanese Patent Publication No. 45-995, polyamides are blended in order to improve the moldability of aromatic polyether resins. It is proposed that. However, aromatic polyether resins and polyamides have very poor compatibility, and molded products obtained by injection molding exhibit a delamination phenomenon and have extremely poor mechanical properties. JP-A No. 57-36150 discloses that, in addition to the above components, a copolymer consisting of a styrene compound and an α,β-unsaturated dicarboxylic acid anhydride is used to improve compatibility and provide excellent mechanical properties. It has been shown that the molding material has properties and chemical resistance.

However, even if nylon 66, which has the highest heat resistance, is selected among the polyamides used in JP-A No. 57-38150, it does not have the soldering heat resistance to withstand the re-opening soldering method, and cannot be used for the above purpose. I can't. Furthermore, JP-A No. 59-27942 discloses that dimensional accuracy, hygroscopicity, etc. can be further improved by using a copolymer obtained from xylylene diamine and aliphatic dicarboxylic acid as the bolyamide component. . However, even in this case, it does not have a high degree of heat resistance that can withstand extreme heat.

Next, the constituent elements of the present invention will be explained in detail.

[Problems to be Solved by the Invention] In view of this situation, the present invention meets the requirements for the above-mentioned uses.
It is a frame designed to provide plastic materials with dimensional stability, electrical properties, heat resistance, solvent resistance, etc.

[Means and effects for solving the problems] According to the present invention, 5 to 50 parts by weight of an aromatic polyether resin, a styrene compound and an α,β-unsaturated carboxylic acid anhydride or α, Thermoplastic with good oil resistance and heat resistance, consisting of 3 to 25 parts by weight of a copolymer containing β-unsaturated carboxylic acid as a component and 35 to 80 parts by weight of a polyamide resin whose crystal melting point is in the range of 285 to 320°C. A resin composition is provided.

The aromatic polyether resin of the present invention has the general formula % [] (where R1, R2, R3, R4, R5, and R6 are the same).
or a C1-4 alkyl group excluding a tert-butyl group, an aryl group, a halogen, a -valent residue such as hydrogen, and R5 and R6 are not hydrogen at the same time. ) as a repeating unit, and the constituent units are [I] or [I] and [II], homopolymers or copolymers, and graft copolymers in which styrene or the like is graft-polymerized to the polymer.

Representative examples of polyphenylene ether homopolymers include poly(2,6-dimethyl-1,4-phenylene) ether, poly(2-methyl-6-ethyl-1,4-phenylene) ether, and poly(2,8-phenylene) ether. -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-8-n-butyl-1,4-phenylene)ether, poly(2-ethyl-6-isopropyl-1,4-
phenylene) ether, poly(2-methyl-6-chloro-1,4-phenylene) ether, poly(2-methyl-
Examples include homopolymers such as 8-hydroxyethyl-1,4-phenylene) ether and poly(2-methyl-8-chloroethyl-1,4-phenylene) ether.

The polyphenylene ether copolymer is a monovalent group such as ortho-cresol or a general formula (where R3, R4, R5, R6 are an alkyl group having 1 to 4 carbon atoms excluding tert-butyl group, an aryl group, /\logen, hydrogen, etc.) (R5 and R6 are not hydrogen at the same time.) 2,3.6-) A polyphenylene ether mainly composed of a polyphenylene ether structure obtained by copolymerizing with an alkyl-substituted phenol such as trimethylphenol. Including copolymers.

Furthermore, styrene alone or a monomer copolymerizable with styrene may be graft copolymerized with the polyphenylene ether.

Styrenic compounds used in the present invention and α, β-
, β-dicarboxylic acid anhydride, or α, β-, β-carboxylic acid as a component include non-rubber reinforced copolymers and impact-resistant rubber reinforced copolymers. Generally, the copolymer used in the present invention can be produced by conventional bulk polymerization, solution polymerization, suspension polymerization, or emulsion polymerization techniques that utilize radical polymerization.

Styrene compounds forming the copolymer used in the present invention include styrene, orthomethylstyrene, paramethylstyrene, dimethylstyrene, metaethylstyrene, chlorstyrene, isopropylstyrene, tertiary-butylstyrene, alpha-methylstyrene, and ethyl vinyl. Toluene, etc., or mixtures thereof are used. α
.

The β-unsaturated dicarboxylic anhydride may be a monomer that can be copolymerized with a styrene compound, such as maleic anhydride, chloromaleic anhydride, citraconic anhydride, butenylsuccinic anhydride, tetrahydrophthalic anhydride, etc. It is. α,β-unsaturated unsaturated fulponic acids include acrylic acid, methacrylic acid, and ethacrylic acid. Furthermore, copolymerizable acrylic esters, methacrylic esters, vinyl cyan compounds, and the like may be used as the third component.

The rubber-reinforced copolymers used in the present invention include polybutadiene rubber, styrene-butadiene rubber, polybutene rubber, hydrogenated styrene-butadiene rubber, acrylonitrile-butadiene rubber, ethylene-propylene rubber, polyacrylate rubber, polyisoprene rubber, It can be obtained by polymerizing the monomers described above in the presence of a rubbery polymer such as natural rubber.

Examples of suitable copolymers used in the present invention include styrene-maleic anhydride copolymer, styrene-maleic anhydride-methacrylic ester copolymer, styrene-maleic anhydride-acrylic ester copolymer, These include styrene-acrylic acid copolymers, styrene-methacrylic acid copolymers, and rubber copolymers thereof.

Furthermore, the copolymer used in the present invention contains 60 to 99% by weight of a styrene compound as a component, and the content of α,β-unsaturated dicarboxylic acid anhydride or α,β-unsaturated carboxylic acid is 1 to 40% by weight. % of a copolymer, or a styrenic compound and an α,β-unsaturated dicarboxylic acid anhydride or α,β
- 60 to 96% by weight of a copolymer containing an unsaturated carboxylic acid as a component and 2 to 30% by weight of a styrene compound;
A copolymer of α,β-unsaturated dicarboxylic acid anhydride or α,β-unsaturated carboxylic acid with 2 to 20% by weight of methacrylic ester or acrylic ester is preferable. In the case of a rubber-reinforced copolymer, the composition of the resin phase excluding the rubber component is preferably within the above range. If the content of styrene compounds is too low, or α
, β-unsaturated dicarboxylic acid anhydride or α, β-unsaturated carboxylic acid, if the content is too small or too large, the mechanical properties such as impact strength of the resin composition will deteriorate, so it is preferable. do not have.

The polyamide used in the present invention has a crystal melting point of 265°C to 32°C.
It is necessary that the temperature is in the range of 0°C, preferably 270°C.
It is a polyamide in the range of ℃ to 300℃. If the melting point is below 265°C, heat resistance, especially heat resistance, will be insufficient, and if it exceeds 320°C, extrusion processability during composition production will be poor, decomposition and deterioration of components will be severe, and quality, especially mechanical It is undesirable because the physical characteristics deteriorate. Examples of preferred polyamides include nylon 48 (polyamide from tetramethylene diamine and adipic acid; melting point 283°C), nylon 44 (polyamide from tetramethylene diamine and co/\hydric acid; melting point 287°C), Polyamide from ethylenediamine and adipic acid; melting point 287°C
), polyamide from p-phenylenediamine and hepta/uccinic acid (melting point 319°C), polyamide from p-cyclohexyldiamine and sepacic acid (melting point 286°C), polyamide from decamethylenediamine and p-phthalic acid (melting point 238°C). The molecular weight of the polyamide is from 5,000 to 5G, 000, preferably from 10,000 to
40,000 range. A particularly preferred polyamide is nylon 4B, which has a melting point of 290 to 295° C. and a relatively high ripening temperature.

The above-mentioned aromatic polyether resin, a copolymer containing a styrene compound and an α,β-unsaturated dicarboxylic acid anhydride or an α,β-unsaturated carboxylic acid as components, and a crystal melting point of 265 to 320°C It is necessary to combine the polyamides within the following range. That is, the aromatic polyether resin is 5 to 50 parts by weight, the styrene copolymer is 3 to 25 parts by weight, and the polyamide is 35 to 80 parts by weight, and more preferably the aromatic polyether resin is 10 to 35 parts by weight. This is a combination of 5 to 15 parts by weight of the styrene copolymer and 40 to 70 parts by weight of the polyamide. The reason for limiting this ratio is that if the aromatic polyether resin is less than 5 parts by weight, the dimensional stability, especially the warp of the molded product, will deteriorate, and if it exceeds 50 parts by weight, the solvent resistance will deteriorate.
Molding fluidity decreases. The styrene copolymer is necessary to improve the compatibility of the system; if it is less than 3 parts by weight, the layers tend to peel off, and if it is more than 25 parts by weight, the heat resistance is impaired.

If the amount of polyamide is less than 35 parts by weight, heat resistance and solvent resistance will be impaired, and if it is more than 80 parts by weight, warping of the molded product and changes in one dimension of electrical properties due to moisture absorption will become large, which is not preferable. It is particularly preferable for the polyamide component to exist as a continuous layer component in the system from the viewpoint of maintaining heat resistance.

Further, in a general embodiment of the present invention, in addition to the above resin composition, fibrous reinforcing agents such as glass fiber, carbon fiber, metal fiber, asbestos, clay, silica, talc, calcium carbonate, wolast, etc. It is preferable to add an inorganic filler such as night and use it as a composite material. In particular, composites with glass fibers are suitable for improving heat resistance and mechanical strength, but addition of reinforcing agents and fillers is not always essential depending on the purpose. The reinforcing agent and filler mentioned above can be used alone or in combination, and the amount thereof is 5 to 150 parts by weight per 100 parts by weight of the above resin composition.
Preferably it is 10 to 70 parts by weight.

Further, other compounding agents can be appropriately added to the resin composition of the present invention. Examples of these are impact strength reinforcing agents, flame retardants, plasticizers, lubricants, colorants, stabilizers, etc.

Examples of the impact strength reinforcing agent include thermoplastic elastomers, rubber-modified polystyrene resins (HIPS), and ABS resins, with thermoplastic elastomers being particularly preferred.

Examples include styrene-butadiene block copolymers, hydrogenated styrene-butadiene block copolymers, ethylene-propylene elastomers, styrene-grafted ethylene-propylene elastomers, thermoplastic polyester elastomers, and 1 to 20 parts by weight. As the flame retardant, aromatic halogen compounds, halogenated polystyrene, halogenated polycarbonate, mixtures of these with antimony oxide, elemental red phosphorus 5 or phosphorus compounds, etc. can be used. Two or more types may be used in combination.

In addition, other thermoplastic resins may be added as appropriate within a range that does not impair the purpose of the present invention. Examples thereof include polystyrene, polyethylene, polypropylene, polybutylene terephthalate, polyethylene terephthalate, polyphenylene sulfide, etc., and the amount of addition is limited to Composition 10 of the invention
The amount is about 1 to 20 parts by weight relative to 0 parts by weight.

As a method for obtaining the resin composition of the present invention, a method of melt-mixing using an extruder, roll mixer, Banbury mixer, Nigoo mixer, etc. can be used.

Regarding the order of melt-mixing, all the components may be melt-mixed at the same time, or a method may be used in which two to three types of components are melt-mixed in advance.

The most standard mixing method uses a twin-screw extruder,
This is a method of melt-kneading at a temperature of 280°C to 340°C.

Further, during melt mixing, it is effective to add a low molecular weight carboxylic acid in an amount of 0.01 to 2% by weight based on the weight of the composition in order to enhance plasticization efficiency and molding fluidity. As the low molecular weight carboxylic acid, oxalic acid, fumaric acid, maleic acid, benzoic acid, maleic anhydride, adipic acid, etc. can be used.

[Example] The present invention will be explained in detail with reference to Examples below. Nylon 46 used in the Examples was synthesized by the method described below.

5 kg of dried 1,4-diaminobutane/adipic acid salt containing an excess amount of diamine of 6.5 mol % based on the amount of adipic acid in an autoclave at a reaction temperature of 220° C.
A prepolymer was prepared by heating under conditions of a reaction time of 3 hours. The obtained prepolymer was cooled after releasing the pressure and then ground to an average particle size of 0.1 to 0.2 mm. Relative viscosity (ηr) measured at 20°C by dissolving 1 g of this prepolymer in 100 g of 88% sulfuric acid
is 1.40.

4 kg of this prepolymer, which had a number average molecular weight of 3,400, was transferred to a stainless steel reaction vessel and heated at 260° C. for 5 hours under normal pressure N2 gas blowing for post-condensation. As a result, white, granular nylon 4B having an ηr of 4.3 and a number average molecular weight of 32,000 was obtained. The melting point measured by DSC method was 293°C.

Examples 1-4. Comparative Examples 1 to 5 Poly(2,8-dimethylphenylene-1,4-ether), nylon 46, nylon 66, styrene-maleic anhydride copolymer with an intrinsic viscosity of 0.82 (25°C, in chloroform) (Maleic anhydride content 10% by weight)
, styrene-methacrylic acid copolymer (methacrylic acid content: 8% by weight), chopped glass fiber strands with a length of 3 mm were fed to a 30φ twin-screw extruder according to the formulation shown in Table 1, and heated at 320°C. The mixture was extruded and kneaded at a temperature and discharge rate of 5 kg/hr to pelletize it. Then, test pieces were prepared using an injection molding machine, and their characteristics were evaluated according to the following test method.

Heating deformation temperature; JIS K 720? tensile strength,
JIS K 7113 Flexural modulus: ASTM-0790 Izot impact strength, JIS K 7110 3A''
Thickness, warpage rate of notched molded product; 150 x 150 x 3 am
Flat plate diagonal measurement molding shrinkage rate, ASTM-1) 1299150 X
150 x 3 am flat plate moisture absorption test; 60°C, 95%
Rate of weight change at RH 124 hours From the results shown in Table 1, Examples 1 to 4 had better heat resistance than the nylon 66 base of Comparative Example 5, and other physical properties were almost the same balance as Comparative Example 5. have.

On the other hand, Comparative Example 1, which does not have a preferred composition, has poor compatibility and poor impact strength, warpage, and moisture absorption; Comparative Example 2 has warpage and moisture absorption; Comparative Example 3 has poor heat resistance and solvent resistance; and Comparative Example 4 has poor compatibility. Solvent resistance is poor.

Example 5 Test pieces of Examples 1 to 4 and Comparative Example 5 (100X
12X 15mm) and glass reinforced polybutylene phthalate resin (Barox 420-9EO) as a reference example.
, glass-reinforced polyethylene phthalate resin (Rynite FR530), and polyphenylene sulfide resin (Rydon R-4) test pieces were immersed for 10 seconds in a slag tank at the temperature shown in Table 2 to determine the degree of deformation. The results are shown in Table 2.

Table 2 Degree of deformation 0...no deformation, 1...slight deformation, 2...slight deformation, 3...obvious deformation, 4...
・Very severe deformation, 5... Severe deformation.

As is clear from Table 2, the test pieces of Examples 1 to 4 have solder heat resistance comparable to that of polyphenylene sulfide resin.

Example 6. Comparative Example 6 Poly(2,8-dimethylphenylene-1,4-ether) with an intrinsic viscosity of 0.84 (25°C, in chloroform), nylon 46, nylon 6B (Leona 1300S)
), styrene-maleic anhydride copolymer (maleic anhydride content 10% by weight), styrene-butadiene hydrogenated block copolymer (Craton 01650 Citrus Co.), Pyro 4 as a flame retardant? , 88PB (8th Ferro ■)
, antimony trioxide according to the formulation shown in Table 3, 30φ2
Supplied to a axial extruder, with a discharge rate of 3 kg/at a temperature of 310°C.
After extrusion kneading at
cation335-1), solvent resistance, flame retardance (
UL-94) was measured, and the results shown in Table 3 were obtained. It can be seen that the examples have better heat resistance than the comparative examples.

Table 3 [Effects of the Invention] As described above, the thermoplastic resin composition of the present invention contains a styrene compound and an α,β-unsaturated carboxylic acid anhydride or an α,β-unsaturated carboxylic acid in an aromatic polyether resin. Copolymer containing acid as a component, crystal melting point 265-320℃
By adding specific amounts of each polyamide resin in the range of 1. heat resistance, which is a feature of aromatic polyether resin,
It has improved oil resistance while taking advantage of its excellent mechanical properties, electrical properties, and dimensional stability, and is especially suitable for applications that require a high degree of heat resistance such as refrigeration and soldering methods.
Its superiority can be demonstrated by using it in applications that require solvent resistance to solvents in a high-temperature vapor state.

Claims (2)

[Claims] (1) 5 to 50 parts by weight of aromatic polyether resin, styrene compound and α,β-unsaturated carboxylic acid anhydride or α
, 3 to 25 parts by weight of a copolymer containing β-unsaturated carboxylic acid as a component, and 35 to 80 parts by weight of a polyamide resin having a crystal melting point in the range of 265 to 320°C, which has good oil resistance and heat resistance. Plastic resin composition. (2) The resin composition according to claim 1, which comprises 5 to 150 parts by weight of a fibrous, flaky or powder reinforcing agent per 100 parts by weight of the thermoplastic resin composition.