JPH04159367A - Resin composition containing pps - Google Patents

Abstract

PURPOSE:To improve impact resistance by dispersing a powdered elastomer in a polyphenylene sulfide resin in such a way that the distance between the surfaces of the elastomer particles falls within a specified range. CONSTITUTION:A polyphenylene sulfide resin having a melt viscosity of 100P or higher and contg. 70mol% or higher repeating units of the formula is melt mixed with a powdered elastomer comprising an ionomer resin pref. having a mol.wt. of 10000-1000000 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 in such a way that the distance between the surfaces of the elastomer particles is 0.2mum or lower, pref. 0.1mum or lower.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Field of Application) The present invention relates to a polyphenylene sulfide resin composition with improved impact resistance.

More specifically, the present invention relates to a polyphenylene sulfide resin composition with improved impact resistance, which is made 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 sophisticated, and meeting these demands has become a technological challenge.

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 comprising 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-mentioned 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. However, the elastomer dispersed in such resin compositions has not always been in an optimal dispersion state.
A sufficient impact resistance improvement effect has not been obtained.

(Problem B to be Solved by the Invention) In view of the above circumstances, an object of the present invention is to obtain a polyphenylene sulfide resin composition that maintains the excellent features of PPS and has improved impact resistance.

(Means for Solving the Problems) As a result of intensive study of the above object, the present inventors have found that polyphenylene sulfide I resin (A) has an elastomer (B).
In the resin composition containing component (B) in component (A), the distance between particle surfaces is 0°2.
The present invention was achieved by discovering that a resin composition having particles dispersed in micrometers or less achieves the above object.

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, etc., and in the polymer obtained by the method described in Japanese Patent Publication No. 45-3368, 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.

H3 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 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 aminotriazur described in JP-A No. 204046 and the like.

In the present invention, in order to improve the impact resistance of the PPS resin, the polyphenylene sulfide resin (A) contains an elastomer (B), and the proportion is such that the elastomer (B) becomes a dispersed phase in the PPS. There is no particular restriction as long as it is a ratio, and in order to obtain the desired effect, (A) /
(B) is preferably blended in a weight ratio of 50150 to 98/2. This is because if the elastomer component exceeds this range, the inherent heat resistance of PPS will be lost, and if it decreases, the desired effect will not be obtained.

Elastomers in the present invention include polyolefin elastomers, polystyrene elastomers, polyamide elastomers, polyester elastomers, polyurethane elastomers, fluorine elastomers, silicone elastomers, shrimp chlorohydrin rubber, acrylic elastomers, polyorganosiloxane rubber, and butyl rubber. , nitrile rubber, chloroprene rubber, styrene
Known rubbers such as butadiene rubber, butadiene rubber, natural rubber, and isoprene rubber can be used, and among them, polyolefin elastomers and polyurethane elastomers can be preferably selected.

Examples of the polyolefin nylastomer include ethylene-propylene rubber, ionomer resin, chlorinated polyethylene, and chlorosulfonated polyethylene, and ionomer resin is particularly preferably used.

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 generally 2; RCH,=CH.

(wherein R is selected from the group consisting of hydrogen and an alkyl group having 1 to 8 carbon atoms);
, 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 copolymers, ethylene/methacrylic acid copolymers, ethylene/itaconic acid copolymers, ethylene/maleic acid copolymers, and ethylene/acrylic acid/acrylic acid copolymers. Methyl methacrylate copolymer, ethylene/methacrylic M/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", M81", Zn! 4
.

Examples of ionomer resins used include ethylene-
Acrylic acid copolymer and metal ions such as Na” and Zn
” in combination.

The molecular weight of ionomer resin is 10,000 to 1,000
,000, preferably 20,000 to 800,000
, more preferably in the range of 30,000 to soo, ooo.

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

Furthermore, examples of the polyurethane nylastomer include cast polyurethane elastomer, thermoplastic polyurethane elastomer, and kneaded polyurethane elastomer, among which thermoplastic polyurethane elastomer is preferably used.

Known thermoplastic polyurethane nylastomers can be used; for example, those sold by Shikinichi Hardy Shuurethane Co., Ltd. under the trade names of "Takelac" and "Elastolan".

In the composition consisting of PPS (A) and elastomer (B) of the present invention, it is important that the elastomer (8) is distributed as a dispersed phase and that the distance between the particle surfaces is 0.2 μm or less, In order to obtain higher impact resistance, the thickness is preferably 0.1 μm or less.

The distance between the particle surfaces 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 by a conventional method, and thin sections are taken. Cut it out, observe it with a transmission electron microscope, and measure the average particle diameter d of the stained phase.

The average particle diameter d refers to the circular phase 5 of each particle calculated from an arbitrary 15 x 15 pm field of view of a thin section directly or by printing it on a photograph from a negative and reading it into an image diffraction device.
Take the number average value of the diameter. However, the arbitrary field of view at this time is
If a skin phase and a core phase are present in the composition, the core phase view 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.

Assuming that the particle diameters are uniform -m- and that they are squarely arranged,
From the average particle diameter d obtained above, the particle surface dark path ML can be calculated using the following formula, and this L is taken as the distance between the particle surfaces here.

L=d((π/6φ)1'3~l) (where φ is the volume fraction of the elastomer) The melt mixing in the present invention is performed by kneading the resin melt in a conventional kneader, roll mill, extruder, etc. The kneading can be carried out using a known device used for extrusion.Types of extruders include:
There are single-screw extruders, twin-screw extruders, co-kneaders, etc., and the composition of the present invention can be obtained using any of the extruders, but the stronger the cross-extrusion, the better the dispersion of particles and the smaller the particle diameter. A twin screw extruder is preferably used.

The mixing temperature is higher than the melting point of PPS, and sufficient kneading is possible within the commonly used range of 280 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 elastomer (B) and reduce the distance between particle surfaces, a polyfunctional compatibilizer is usually used. Examples of this polyfunctional compatibilizer include compounds having an amino group, hydroxyl group, carboxyl group, incyanate group, carbodiimide group, epoxy group, maleic anhydride group, etc. in the molecule, and among them, compounds having an isocyanate group. is preferably used.

Furthermore, in the resin composition of the present invention, an inorganic and/or organic filler can be added to the resin portion as necessary to improve rigidity and the like.

Suitable fillers include glass fiber, carbon fiber, i-gold 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, aklebalgite,
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.

In addition, the resin composition of the present invention may further contain aromatic hydroxy derivatives such as 2-ethylhexylnyl-hydroxybenzoate, sulfonic acid amides such as benzenesulfonamide, etc., within the range where the structure of the composition is maintained. In addition to the plasticizer, 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, a rust preventive, etc. may be added.

The resin composition of the present invention can be prepared by various known methods. For example, there is a method in which the raw materials are uniformly mixed in advance in a mixer such as a tumbler 1 or a Henschel mixer, then fed into a -screw or twin-screw extruder, etc., melt-kneaded, and then prepared as pellets.

The melting crosstalk 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, thermal deterioration of the ethylene copolymer (B) may occur. Care must be taken as gelation may occur.

In the present invention, the Izot impact strength is AST
It was carried out according to MD-256.

(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 Tonibuen ■) 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,
T-40” twin screw extruder, cylinder temperature: 290~
Pelletized at 300°C.

In addition, when glass fiber was blended, the pelletized pellets were melt-kneaded with glass fiber again using an extruder. The cylinder temperature of the obtained pellet is 240°C in the hopper part, 290°C in the center part, 300°C in the tip part.
The mold temperature was set at 140°C, test pieces were 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
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 1-3 PPS powder (Tovren T-4) was dried at 140'C for 3 hours, then 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 = 290-30
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 are 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 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.

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

Table 1 PPS Nido-Bren Kobata W “Cho-4” MDI; 4,4'-diphenylmethane diisocyanate 2
- Elastomer 1: Made by Mitsui Dupont Chemika 4 "High Sewing Machine 1F 06J Elastomer 2: Made by Hardy Soy Urethane Kogyo Kogyo""ElastlanC60Aj"
l J elastomer 3: Shikinichi Verdeino Yuurethane Co., Ltd. "Elastlan C70AW J Table 2 (fiber diameter 13 μm, fiber length 3) (Effects of the invention) The resin composition of the present invention has excellent thermal stability, mechanical Excellent physical properties,
Moreover, it is a resin composition with good dispersion of the elastomer component and excellent impact resistance, and is a highly practical molding material with excellent physical properties as an engineering plastic.

Claims (1)

[Claims] In a resin composition comprising a polyphenylene sulfide resin (A) containing an elastomer (B), the component (B) in the component (A) has a particle surface distance of 0.2.
A resin composition that is dispersed in micrometers or less.