JPH04159366A - Resin composition containing pps - Google Patents

Abstract

PURPOSE:To improve impact resistance and weld strength by dispersing a powdered elastomer having specified particle diameters in a polyphenylene sulfide resin. CONSTITUTION:A polyphenylene sulfide resin having a melt viscosity of 100P or higher is melt-mixed with a powdered elastomer comprising an ionomer resin pref. having a mol.wt. of 10000-100000 in a wt. ratio of the former to the latter of (50:50) to (98:2) at 280-320 deg.C, and the resulting mixture is pelletized to give a resin compsn. comprising the polyphenylene sulfide resin and the elastomer dispersed therein as particles having diameters of 0.5mum or lower.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a polyphenylene sulfide resin composition that has improved impact resistance and excellent weld strength.

More specifically, the present invention relates to a polyphenylene sulfide resin composition having improved impact resistance and excellent weld strength, which is obtained by dispersing an elastomer in a polyphenylene sulfide resin in a specific dispersion state.

(Prior Art) The field of application of engineering plastics has been expanding more and more in recent years, and in particular, their use in the automobile, electrical, and electronic fields has increased significantly. Along with this, user demands for plastics have become more diverse and highly functional, and responding to these demands has become a technological 1lff.

However, these diversified and highly functional demands cannot be fully met with a single material alone, and therefore polymer alloys have recently been actively used to meet these demands.

A resin composition consisting of a polyphenylene sulfide resin (hereinafter referred to as PPS) and an elastomer is a known polymer alloy, and was developed against the background of the above requirements. In other words, PPS is known as a resin with excellent flame retardancy, heat resistance, and chemical resistance, but its impact strength is not necessarily satisfactory, and for this reason, alloying with elastomers has improved impact resistance. trying to improve.

For example, in JP-A-64-26671, an olefin copolymer is dispersed in particles having a diameter of 3 μm or less to improve impact resistance. However, although impact resistance is improved with such a particle size, sufficient weld strength cannot be obtained.

(Problems to be Solved by the Invention) In view of the above circumstances, an object of the present invention is to develop a polyphenylene sulfide resin composition that retains the excellent features of PPS, has improved impact resistance, and has excellent weld strength. It's about getting.

(Means for Solving the Problems) As a result of intensive study of the above object, the present inventors added nylastomer (B) to polyphenylene sulfide resin (A).
It has been discovered that a resin composition containing component (B) in which component (B) is dispersed in component (A) with a particle size of 0.5 μm or less achieves the above object, and the present invention has been made. This invention has been achieved.

The present invention will be explained in detail below.

P P S (A) used in the present invention is a polymer containing 70 mol% or more, more preferably 90 mol% or more of repeating units represented by the structural formula:.

If the content of the repeating unit is less than 70 mol%, heat resistance will be impaired, which is not preferable.

PPS generally includes a polymer with a relatively small molecular weight obtained by the production method typified by Japanese Patent Publication No. 45-3368, and a polymer with an essentially low molecular weight obtained by the production method typified by Japanese Patent Publication No. 52-12240. There are linear polymers with relatively high molecular weight, and in the case of the polymer obtained by the method described in the above-mentioned Japanese Patent Publication No. 45-33ε8, after polymerization, it can be heated in an oxygen atmosphere or treated with peroxide. It is also possible to increase the degree of polymerization and use it by adding a crosslinking agent such as PPS and heating it, and in the present invention, it is possible to use PPS obtained by any method.

Furthermore, less than 30 mol% of the repeating units of PPS can be composed of repeating units having the following structural formula, etc.

The melt viscosity of PPS used in the present invention is not particularly limited as long as it is possible to obtain a molded product, but in terms of the toughness of PPS itself, it is 100 poise or more, and in terms of moldability it is 10,000 poise or more. Poise or less is more preferably used. Particularly preferred is a range of 1,000 to 5,000 poise.

Furthermore, for the purpose of controlling the degree of crosslinking of PPS, common peroxide crosslinking agents and crosslinking accelerators such as thiophosphinic acid metal salts described in JP-A-59-131650,
or JP-A-58-204045, JP-A-58-
It is also possible to incorporate crosslinking inhibitors such as dialkyltin dicarboxylate and aminotriazole described in JP-A No. 204046 and the like.

In the present invention, polyphenylene sulfide resin (A
) is made to contain elastomer (B), but the proportion is not particularly limited as long as the elastomer (B) forms a dispersed phase in PPS; in order to obtain the desired effect, (
A) /(B) = 50150~98/2 weight! It is preferable to mix the elastomer component in a ratio exceeding this range.
Also, if the amount decreases, the desired effect cannot be obtained.

Elastomers in the present invention include polyolefin elastomers, polystyrene elastomers, polyamide elastomers, polyester elastomers, polyurethane elastomers, fluoroelastomers, silicone elastomers, shrimp chlorohydrin rubber, acrylic elastomers, polyorganosiloxane rubber, butyl rubber, Known rubbers include nitrile rubber, chloroprene rubber, styrene-butadiene rubber, butadiene rubber, natural rubber, and isoprene rubber, among which polyolefin elastomers are preferably selected.

Examples of the polyolefin elastomer include ethylene-propylene rubber, ionomer resin, chlorinated polyethylene, and chlorosulfonated polyethylene, with ionomer resin being particularly preferred.

The method for producing the ionomer resin preferably used in the present invention is already well known (Japanese Patent Publication No. 39-6810).
It is produced by reacting a base copolymer with a metal compound capable of ionizing the copolymer.

The base copolymer is composed of an α-olefin represented by the general formula;
, a carboxylic acid having a β-ethyleneene saturated group and 1 to 2 carboxyl groups,
α-olefin-monocarboxylic acid copolymers are particularly suitable.

Examples of base copolymers that can be suitably used include ethylene/acrylic acid copolymer, ethylene/methacrylic acid copolymer, ethylene/itaconic acid copolymer, ethylene/maleic acid copolymer, ethylene/acrylic W1/ Methyl methacrylate copolymer, ethylene/methacrylic acid/vinyl acetate copolymer, ethylene/acrylic acid/vinyl alcohol copolymer, ethylene/propylene/acrylic acid copolymer, ethylene/styrene/acrylic acid copolymer, ethylene /methacrylic acid/acrylonitrile copolymer, ethylene/vinyl chloride/acrylic acid copolymer, ethylene/chlorotrifluoroethylene/methacrylic acid copolymer, polyethylene/acrylic acid graft copolymer, polypropylene/acrylic acid graft copolymer etc. can be mentioned.

In addition, when the base copolymer is an α-olefin-monocarboxylic acid copolymer, the metal ion is 1 to 3
Those with a valence of valence (e.g., Na''', K''
, Li'', Cu'', Be'', HN+, Zn'', A1 copolymer, etc.) are suitable; Examples of ionomer resins in which ``, K'', Li') are suitable and used include combinations of ethylene-acrylic acid copolymers and metal ions such as Na'', Zn''.

The molecular weight of the ionomer resin is 10,000 to 1,00
0°000, preferably 20,000~soo,oo
o, more preferably in the range of 30,000 to 500,000.

The ionomer resin used in the present invention is sold under the trade name "Himilan" by DuPont Mitsui Polychemicals.

Examples of the polyurethane elastomer include cast polyurethane elastomers, thermoplastic polyurethane elastomers, and kneaded polyurethane elastomers, among which thermoplastic polyurethane elastomers are preferably used.

As this thermoplastic polyurethane elastomer, well-known ones can be used, and for example, those sold by Shikinichi Birdy Shurethane Co., Ltd. under the trade names of ``Takelac'' and ``Elastlan''.

In the composition of the present invention consisting of PPS (A) and nilastomer (B), it is important that the elastomer (B) is distributed as a dispersed phase and dispersed with a particle size of 0.5 μm or less. In order to obtain high impact resistance and weld strength, the thickness is preferably 0.3 μm or less.

The particle size of the elastomer (B) in the present invention is defined as follows.

A composition consisting of PPS and an elastomer is stained with a dye such as ruthenium tetroxide or osmium tetroxide using a conventional method, and thin sections are cut out and observed with a transmission electron microscope to determine the average particle size of the stained phase. This value is taken as the particle size. The average particle diameter at this time is
After printing a 5 x 15 μm field of view directly or from a negative into a photograph, it is read into an image diffraction device and used as the number average value of the circular phase 5 diameter of each particle calculated from this. However, as the arbitrary field of view at this time, if the composition has a skin phase and a core phase, the field of view of the core phase is used. Furthermore, when inputting a photograph to the image diffraction device, if the dyed boundary is unclear, the photograph is traced and this diagram is used to input the data to the image diffraction device.

The melt-kneading in the present invention can be carried out using a known device such as a kneader, roll mill, or extruder, which is normally used for kneading resin melts. Types of extruders include single-screw, twin-screw, co-kneader, etc. The composition of the present invention can be obtained using any extruder, but the stronger the kneading, the better the dispersion of the particles. A twin-screw extruder is preferably used because the particle size becomes smaller.

The kneading temperature is higher than the melting point of PPS, and the commonly used 2
It can be sufficiently kneaded in the range of 80 to 340°C. Further, it is preferable that PPS be pre-dried as a pre-treatment and cross-talk be performed in an inert gas atmosphere.

Further, in order to improve the dispersion state of the nilastomer (B) and reduce the particle size, a polyfunctional compatibilizer is usually used. Examples of this multifunctional compatibilizing agent include compounds having amino groups, hydroxyl groups, carboxyl groups, isocyanate groups, carbodiimide groups, epoxy groups, maleic anhydride groups, etc. in the molecule, and even compounds having isocyanate groups. Furthermore, in the resin composition of the present invention, an inorganic and/or organic filler can be added to the greasy portion as necessary to improve rigidity and the like.

Suitable fillers include glass fiber, carbon fiber, metal fiber, aramid fiber, potassium titanate, asbestos, silicon carbide, ceramic, silicon nitride, barium sulfate, calcium sulfate, kaolin, clay, pyrophyllite,
bentonite, sericite, zeolite, mica, mica, nephelinsinite, talc, atalpulgite,
Wollastonite, PMF, ferrite, calcium silicate, calcium carbonate, magnesium carbonate, dolomite, zinc oxide, titanium oxide, magnesium oxide, iron oxide,
Mention may be made of reinforcing fillers such as molybdenum disulfide, graphite, gypsum, glass beads, glass powder, glass balloons, quartz, and quartz glass.

Further, the resin composition of the present invention may further contain aromatic hydroxy derivatives such as 2-ethylhexyl-p-hydroxybenzoate, sulfonic acid amides, such as benzenesulfone, within the range where the structure of the composition is maintained. In addition to a plasticizer such as amide, a small amount of a mold release agent, a coupling agent, a coloring agent, a lubricant, a heat stabilizer, a weather stabilizer, a foaming agent 1, a rust preventive, etc. may be added.

The resin composition of the present invention can be prepared by any known method.6 For example, raw materials may be prepared in advance in a tumbler or
After uniformly mixing with a mixer such as a shell mixer, −
After feeding into a shaft or twin-screw extruder, etc., and melting and kneading,
There is a method of preparing it as a pellet.

In addition, the melt-kneading temperature is preferably 280 to 320"C; if it is less than 280"C, the melting of PPS may become insufficient, and if it exceeds 320"C, the ethylene copolymer (B
) may cause thermal deterioration or gelation, so care must be taken.

In the present invention, tensile strength and 7412114 strength were measured according to ASTM D-638 and D-256, respectively.

(Example) The present invention will be explained in further detail by giving examples below, but the present invention is not limited thereto.

Examples 1 to 9 After drying PPS powder (T-4 manufactured by Tobuen ■) at 140°C for 3 hours, the temperature was lowered to 50°C, PPS, elastomer, and 4,4゛-diphenylmethane diisocyanate were blended, and 5 After mixing in a Henschel mixer in a nitrogen atmosphere for minutes,
-40” twin screw extruder, cylinder temperature: 290-30
Pelletized at 0°C.

In addition, when glass fiber was blended, the pelletized pellets were melt-kneaded with the glass fiber again using an extruder. The obtained pellets were heated to a cylinder temperature of 240°C for the hopper part, 290°C for the center, and 300°C for the tip.
Next, the mold temperature was set at 140°C, a test piece was obtained by a normal injection molding method, and various physical properties were measured.

This test piece was stained with ruthenium tetroxide, thin sections were cut, and transmission electron micrographs were taken. For observation, a 1200Ex■ transmission electron microscope manufactured by JEOL Ltd. was used.

Furthermore, for image analysis, IP-1000 manufactured by Asahi Kasei Kogyo Co., Ltd.
Images were input from the above-mentioned electron microscope using an image analysis device. The results obtained are shown in Tables 1 and 2.

Comparative Examples 1 to 3 After drying PPS powder [Tovren T-4] at 140"C for 3 hours, the temperature was lowered to 50°C, PPS and elastomer were blended, and mixed in a Henschel mixer in a nitrogen atmosphere for 5 minutes. After that, ``BT-'' made by Plastic Engineering Research Institute ■
40” twin screw extruder, cylinder temperature = 290-300
pelletized at °C.

In addition, when glass fiber was blended, the pelletized pellets were melt-kneaded with the glass fiber again using an extruder. The obtained pellets were heated to a cylinder temperature of 240°C in the hopper part, 290°C in the center, and 300°C in the tip part.
In step C, the mold temperature was set at 140''C, a test piece was obtained by a normal injection molding method, and various physical properties were measured.

This test piece was stained with ruthenium tetroxide, thin sections were cut, and transmission electron micrographs were taken. For observation, a 1200EX ■ transmission electron microscope manufactured by JEOL ■ was used.

Further, for image analysis, an IP-1000 image analysis device manufactured by Asahi Kasei Corporation was used, and images were input from the above-mentioned electron microscope. The results obtained are shown in Tables 1 and 2.

(Effects of the invention) The resin composition of the invention has excellent thermal stability and mechanical properties,
In addition, the elastomer component has a good dispersion state, and has good impact resistance and
It is a resin composition with excellent weld strength, and is a highly practical molding material with excellent physical properties as an engineering plastic.

(1 or 1 person)

Claims (1)

[Claims] In a resin composition comprising a polyphenylene sulfide resin (A) containing an elastomer (B), the component (B) is dispersed in the component (A) with a particle size of 0.5 μm or less. A resin composition made of