JPH0764982B2 - High specific gravity composite resin composition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial application] The present invention relates to a novel high specific gravity composite resin composition. More specifically, the present invention is suitable for use as a material for structural parts and precision parts in various fields such as electric / electronics, machinery, automobiles, or general industrial parts, furniture, daily necessities, and the like, and its appearance and mechanical properties. A zinc metal-based filler, which has features such as excellent retention properties in the molding machine and good moldability, as well as excellent pellet productivity, has been added. And a high specific gravity composite resin composition comprising

[Prior Art] Thermoplastic resins are easier to process than metal materials, have excellent corrosion resistance, are lightweight, and are relatively inexpensive. Therefore, in recent years, mechanical parts, precision parts, general industrial parts, furniture,
It is widely used in many fields as a material for Sunday sundries and structural materials.

However, the thermoplastic resin is generally inferior to the metal material in mechanical properties such as tensile strength, impact resistance, and hardness, and is not necessarily satisfactory in heat resistance and dimensional stability. Further, there is a problem in that the lightness, which is a characteristic of the product, may impair the image as a product.

Therefore, in order to solve such problems, various composite resin compositions in which a thermoplastic resin is mixed with a metal-based filler have been proposed so far. For example, a composite resin composition is known in which thermoplastic resin such as polypropylene, polyethylene, polyamide, polyethylene terephthalate, and polybutylene terephthalate is mixed with particles of a metal filler such as zinc, zinc oxide, copper, and iron.

In this case, when the amount of the metal particles is small, there is no problem, but when the amount of the metal particles is increased to obtain a high specific gravity material, especially when the amount of the metal particles is 50% by weight or more. Because the resin and the metal particles have poor compatibility,
(1) Abrasion damage of the kneader or molding machine due to metal particles is severe, (2) Metal particles agglomerate and adhere to the inside of the kneader or molding machine, and the retention characteristics are deteriorated by sintering or solidification. , Productivity of pellets and molded products is extremely deteriorated, (3) resin is easily deteriorated by metal particles and continuous moldability is poor, (4) appearance and mechanical strength of molded products, particularly impact strength are not sufficient, (5) During continuous production of molded products,
There are drawbacks such as large differences in weight and density of molded products, and variations in dimensional accuracy. Moreover, especially when the amount of the metal particles to be blended exceeds 70% by weight, such defects become remarkable, and the moldability is extremely deteriorated. Even in injection molding, the gate diameter must be large to form a direct gate. It is difficult to mold, it is limited to small parts molding, and it is not suitable for large moldings.

[Problems to be Solved by the Invention] The present invention overcomes the drawbacks of the high specific gravity composite resin composition obtained by blending such a conventional metal-based filler, and is excellent in appearance and mechanical properties. Molded products can be manufactured with good retention characteristics in the molding machine and with good productivity, and also with excellent pellet productivity, and they do not cause significant abrasion damage to the kneader or molding machine. The present invention has been made for the purpose of providing a high specific gravity composite resin composition prepared by blending a metal-based filler having excellent characteristics.

[Means for Solving Problems] The inventors of the present invention have conducted extensive studies to develop a high specific gravity composite resin composition containing a metal-based filler having the above-mentioned excellent characteristics, and as a result, By blending a zinc metal-based filler and a modified polyolefin as a binder at a predetermined ratio in at least one polymer matrix selected from a specific thermoplastic resin and a polymer elastic body, the purpose thereof can be improved. Based on this finding, the present invention has been completed.

That is, the present invention relates to (A) (a) polyethylene resin, polyvinyl chloride resin, polyimide resin, polyester resin, polyacetal resin, polycarbonate resin, polyaromatic ether or thioether resin, polysulfone resin. A thermoplastic resin composed of a styrene resin and an acrylate resin, and 5 to 50 parts by weight of at least one kind selected from (b) a polymer single substance.
1 to 10 parts by weight of the (C) modified polyolefin per 100 parts by weight of the total amount of the (A) component and the (B) component, containing 95 to 50 parts by weight of the (B) zinc metal-based filler. A high specific gravity composite resin composition characterized by being blended.

Hereinafter, the present invention will be described in detail.

In the composition of the present invention, as the component (A), that is, the polymer matrix, (a) polyethylene resin, polyvinyl chloride resin, polyimide resin, polyester resin, polyacetal resin, polycarbonate resin, polyaromatic resin At least one selected from a thermoplastic resin composed of an ether or thioether resin, a polysulfone resin, a styrene resin and an acrylate resin and (b) a rubber-like polymer elastic body is used.

As the polyethylene-based resin, ethylene homopolymer or ethylene as a main component, a copolymer with an unsaturated monomer copolymerizable with ethylene is used, and as a typical example, high density, medium density, Examples thereof include low density polyethylene, linear polyethylene, ultra high molecular weight polyethylene, ethylene-vinyl acetate copolymer, ethylene-ethyl acrylate copolymer and the like.

Examples of the polyvinyl chloride-based resin include a vinyl chloride homopolymer and a copolymer of vinyl chloride and an unsaturated monomer copolymerizable with vinyl chloride. Examples of the copolymer include vinyl chloride-acrylic acid ester copolymer, vinyl chloride-methacrylic acid ester copolymer, vinyl chloride-ethylene copolymer, vinyl chloride-propylene copolymer, vinyl chloride-vinyl acetate copolymer. Examples thereof include polymers and vinyl chloride-vinylidene chloride copolymers. Further, those obtained by post-chlorinating these polyvinyl chloride resins to increase the chlorine content can also be used.

Polyimide resins include polyimides and polyamideimides, and specific examples of polyimides include pyromellitic dianhydride and diaminodiphenyl ether, 3,4,
Examples thereof include those obtained from combinations of 3 ′, 4′-benzophenone tetracarboxylic acid anhydride and diaminodiphenyl ether, bismaleimide and diaminodiphenylmethane, and specific examples of polyamideimides include trimellitic anhydride and diamino The thing obtained from the combination with diphenyl ether etc. can be mentioned.

Examples of the polyester resin include those obtained by polycondensing an aromatic dicarboxylic acid and an alkylene glycol,
Specific examples include polyethylene terephthalate and polybutylene terephthalate.

Examples of the polyacetal resin include homopolymer polyoxymethylene and formaldehyde-ethylene oxide copolymer obtained from trioxane and ethylene oxide.

The polycarbonate resin can be obtained by a 4,4′-dihydroxydiarylalkane polycarbonate, particularly a phosgene method in which bisphenol A and phosgene are reacted, or a transesterification method in which bisphenol A and a carbonic acid diester such as diphenyl carbonate are reacted. Bisphenol A-based polycarbonate is preferably used. In addition, modification in which a part of bisphenol A is replaced with 2,2-bis (4-hydroxy-3,5-dimethylphenyl) propane or 2,2-bis (4-hydroxy-3,5-dibromophenyl) propane Bisphenol A-based polycarbonate and flame-retardant bisphenol A-based polycarbonate can also be used.

The polyaromatic ether or thioether-based resin has an ether bond or a thioether bond in the molecular chain, and examples of such a resin include polyphenylene oxide, polyphenylene oxide grafted with styrene, and polyetheretherkene. , Polyphenylene sulfide and the like.

The polysulfone-based resin has a sulfone group in the molecular chain. Examples of such a resin include polysulfone obtained by condensation polymerization of bisphenol A and 4,4′-dichlorodiphenylsulfone, and phenylene group having an ether group. Examples thereof include polyether sulfone having a structure linked to the p-position via a sulfone group, and polyallyl sulfone having a structure in which a diphenylene group and a diphenylene ether group are alternately linked via a sulfone group.

Examples of the styrene-based resin include homopolymers such as styrene and α-methylstyrene, copolymers thereof, and copolymers with unsaturated monomers copolymerizable therewith. As typical examples, general-purpose polystyrene, impact-resistant polystyrene, heat-resistant polystyrene (α-methylstyrene polymer), acrylonitrile-butadiene-styrene copolymer (ABS), acrylonitrile-styrene copolymer (AS), acrylonitrile- Chlorinated polyethylene-styrene copolymer (ACS), acrylonitrile-ethylene propylene rubber-styrene copolymer (AES) and the like can be mentioned.

Examples of the acrylate resin include methacrylic acid ester polymers and acrylic acid ester polymers, and examples of these monomers include methacrylic acid and acrylic acid methyl, ethyl, n-propyl, isopropyl,
Butyl ester and the like are used, and as the industrial molding material, methyl methyl acrylate resin can be mentioned as a typical one.

On the other hand, the polymer elastic body includes natural rubber, synthetic rubber and elastomer, and examples of the synthetic rubber and elastomer include butadiene polymer (BR) butadiene-styrene copolymer (SBR) and butadiene-allylonitrile copolymer. Butadiene-based synthetic rubbers such as polymer (NBR), styrene-butadiene-acrylonitrile copolymer, chloroprene polymer (CR), isoprene polymer rubber (synthetic natural rubber), isobutylene-isoprene copolymer rubber (butyl rubber, IIR) , Acrylonitrile-isoprene copolymer rubber, isobutylene polymer rubber, ethylene-propylene copolymer rubber, ethylene-vinyl acetate copolymer rubber, chlorinated polyethylene, chlorosulphonated polyethylene,
Urethane rubber, silicon rubber, fluorine rubber, acrylic rubber, epichlorohydrin rubber, propylene oxide rubber, polyester elastomer, polyacrylate elastomer, polyolefin elastomer, polyvinyl chloride elastomer, styrene-butadiene copolymer elastomer, polystyrene elastomer, Examples thereof include polyamide elastomers and polyurethane elastomers.

In the composition of the present invention, each polymer compound mentioned as the component (A) may be used alone,
You may use it in combination of 2 or more type.

In the composition of the present invention, a zinc metal-based filler is used as the component (B). Examples of the zinc metal-based filler include zinc powder, metal powder coated with zinc, metal compound powder, and zinc oxide powder. These may be used alone or in combination of two or more. You may use.

Examples of the metal powder or metal compound powder surface-coated with zinc include iron, iron oxide, copper, and lead oxide powders. There is no particular limitation on the method of coating the surface of such metal powder or metal compound powder with zinc. For example, (1) a method of spray-coating the metal powder or the metal compound powder with molten zinc; It is possible to use a method in which a metal powder or a metal compound powder is added to and stirred. The thickness of zinc coated on the surface is preferably in the range of 0.5 to 3 µ. The particle size of the powder is usually selected in the range of 1 to 15 μm, preferably 4 to 6 μm.

In the composition of the present invention, a modified polyolefin is blended as the component (C). This modified polyolefin is a polyolefin in which a polar group such as a carboxyl group is added by a polymer reaction in which a peroxide or other reactant is allowed to act on the polyolefin, and examples thereof include unsaturated organic acids or derivatives thereof such as acrylic acid and methacrylic acid. Unsaturated organic acids such as maleic acid and itaconic acid, maleic anhydride,
Itaconic anhydride, anhydrides of unsaturated organic acids such as citraconic anhydride, esters of unsaturated organic acids such as methyl acrylate, monomethyl maleate, amides of unsaturated organic acids such as acrylic acid amide, fumaric acid monoamide, itacone Unsaturated organic acid imide such as acid imide is usually added in an amount of 0.05 to 20 relative to 100 parts by weight of ethylene or propylene polymer.
Examples include those added by parts by weight and modified by a graft method. In this modification, an organic peroxide such as benzoyl peroxide, lauroyl peroxide, dicumyl peroxide or t-butyl hydroperoxide is used to accelerate the modification polymerization.

In addition to the above, glycidyl acrylate, glycidyl methacrylate, glycidyl methacrylate, vinyl glycidyl ether, those graft-modified with unsaturated epoxides such as allyl glycidyl ether, and the like, at the time of such graft modification, other than the above, It is also possible to use those to which liquid rubber such as hydroxylated polybutadiene is added.

One of these modified polyolefins may be used, or 2
You may use it in combination of 2 or more types. By blending this modified polyolefin, the compatibility of the polymer matrix of the component (A) and the zinc metal-based filler of the component (B) can be improved, and the impact strength of the resulting molded article can be increased. Can be made.

The blending ratio of the component (A) and the component (B) in the composition of the present invention is selected in the range of 5:95 to 50:50 by weight, preferably 10:90 to 25:75. The component (C) is added in an amount of 1 to 10 parts by weight, preferably 1 to 5 parts by weight, based on 100 parts by weight of the total amount of the components (A) and (B). If the compounding amount of the component (C) is less than 1 part by weight, the object of the present invention cannot be achieved, and if it exceeds 10 parts by weight, phase separation occurs during molding and the resin layer tends to peel off.

In the composition of the present invention, if desired, an inorganic filler or an organic filler can be blended within a range not impairing the object of the present invention. The shape of the filler compounded as desired may be powdery, granular or fibrous.

Examples of the inorganic filler include metal powders other than zinc such as iron, copper, lead, aluminum, nickel, chromium, manganese, tin, and titanium, oxides of these metals, silica, diatomaceous earth, and magnesium oxide. Antimony oxide, barium ferrite, strontium ferrite, beryllium oxide, pumice, pumice balloon, oxides such as alumina fiber, hydroxides such as aluminum hydroxide, magnesium hydroxide and basic magnesium carbonate, calcium carbonate,
Magnesium carbonate, dolomite, carbonate such as dawsonite, calcium sulfate, barium sulfate, ammonium sulfate, sulfate or sulfite such as calcium sulfite, talc, clay, mica, asbestos, glass fiber, glass balloon, glass beads, calcium silicate, Silicates such as montmorillonite and bentonite, carbons such as carbon black, graphite, carbon fibers and hollow carbon spheres, molybdenum sulfide, boron fibers, zinc borate, barium metaborate, calcium borate, sodium borate, silicon carbide Examples thereof include fibers, brass fibers, single crystal potassium titanate, and lead zirconate titanate.

These inorganic fillers may be used alone or in combination of two or more.

On the other hand, examples of the organic filler include shell fiber such as fir shell, wood powder, cotton, jute, paper strip, cellophane piece, aromatic polyamide fiber, cellulose fiber, nylon fiber, polyester fiber and polypropylene fiber. You can These organic fillers may be used alone or in combination of two or more, and may be used in combination with the inorganic filler.

Further, in the composition of the present invention, if desired, various additives usually used in the resin composition, for example, a lubricant, a colorant,
Stabilizers, antioxidants, ultraviolet absorbers, antistatic agents, flame retardants, plasticizers, foaming agents and the like can be added.

The high specific gravity composite resin composition of the present invention has a required amount of the above (A).
The component, the component (B), the component (C), and various fillers and additives used as desired can be prepared by melt-kneading and complexing them in a conventional manner. Melt-kneading can be performed, for example, by a Henschel mixer, a single-screw or twin-screw extruder,
It can be carried out by a method using a Banbury mixer, a roll or the like, and other usual methods, but it is particularly preferable to use a Henschel mixer, an extruder or a Banbury mixer.

The composite resin composition of the present invention can be formed into a molded product having a desired shape by a conventionally used molding method such as injection molding, extrusion molding or press molding, and the raw material components are blended. By appropriately changing the amount, it is possible to obtain a molded article suitable for various uses and having excellent secondary workability. Examples of this application include structural parts and precision parts in various fields such as electric / electronics, machinery, automobiles, general industrial parts, furniture and daily sundries. Specifically, fly holes, gears, pulleys, etc. , Rotating materials for power transmission in all fields such as cams, or housing materials such as players, radio-cassettes and speaker boxes in the acoustic material field, structural materials such as chassis and turntables, sound insulation materials in various fields,
Soundproofing materials, vibration damping materials, electromagnetic wave shielding materials, furniture, kitchen parts, stationery, toys, fishing gear and the like can be mentioned.

[Effect of the Invention] The high specific gravity composite resin composition of the present invention comprises a zinc metal filler and a modified polyolefin in at least one polymer matrix selected from a specific thermoplastic resin and a polymer elastomer. Which has a good retention property in the molding machine, and is a molded product with excellent appearance and mechanical properties.
In addition to being able to be produced with good moldability, it is also excellent in pellet productivity, and further does not cause significant abrasion damage to the kneader or molding machine, and the secondary workability of the molded product is good, etc., It has excellent characteristics.

Since the composition of the present invention has such excellent characteristics, for example, structural parts and precision parts in various fields such as electric / electronic, machine, and automobile, or general industrial parts,
It is preferably used as a material for furniture and daily necessities.

EXAMPLES Next, the present invention will be described in more detail with reference to Examples.
The invention is in no way limited by these examples.

The physical properties of the composition and the molded product were evaluated according to the methods described below.

(1) Pellet productivity The state of the strands when extruded with a single screw extruder at a composition temperature of 240 to 350 ° C was evaluated.

○: No abnormality △: Strands partially foam, but there is no hindrance to production ×: Strands foam and tend to solidify in the cylinder (2) Formability 90 × 150 × 70 mm, 5 mm thick pin gate (1 mmφ) Using a injection molding machine (TOSHIBA MACHINE, IS 125), the cylinder temperature of 220-300 ℃, mold temperature of 75-100 ℃,
The shape reproducibility and the injection pressure at the time of injection molding under the standard conditions of an injection pressure of 60 kg / cm ² and an injection time of 20 seconds were evaluated.

○: Good △: Partial sink mark and higher injection pressure than standard conditions ×… Part of the molded product was missing, and injection pressure was 100 kg / cm
It must be at least ² (gauge pressure).

(3) Retention characteristics A cylinder temperature was set to 250 ° C in an injection molding machine (manufactured by Toshiba Machine Co., IS 125) to retain the composition, and its decomposition and solidification state were evaluated.

○: Decomposition and no solidification even after staying for 1 hour or more △… Decomposition and solidification after 30 minutes of residence ×… Decomposition and solidification at 5 minutes of residence (4) Izod impact strength Measured according to ASTM D-256 .

(5) Tensile strength Measured according to ASTM D-638.

The polymer matrix and zinc metal-based filler used were as follows.

(A) Polymer matrix (a) Thermoplastic resin PBT… Polybutylene terephthalate (Mitsubishi Kasei, 5010) PET… Polyethylene terephthalate (Unitika, MA-2101) POM… Polyacetal (Asahi Kasei, 3010) PE… Polyethylene (Idemitsu) Petrochemical, 110J, MI = 14g / 10min) ABS… Acrylonitrile-butadiene-styrene resin (Nippon Synthetic Rubber, JSR-35) PC… Polycarbonate (Idemitsu Petrochemical, 2500) PVC… Polyvinyl chloride (Shin-Etsu Polymer) Manufactured by JE-102F) PMMA …… -polymethylmethacrylate (manufactured by Asahi Kasei, 50N) PPO… polyphenylene oxide (engineering ring plastics, 731J) PSO… polysulfone (Nissan Chemical Co., P-1700) PI ・ ・ ・ polyimide Far East, SP-1) PPS ... Polyphenylene sulfide (Shin-Etsu Polymer, Ryton R-8) B) Rubber-like polymer elastic body SBR: Styrene-butadiene rubber (Nippon Synthetic Rubber, JSR-1500) EPR: Ethylene propylene rubber (Nippon Synthetic Rubber, EP-07P) Silicon rubber (Shin-Etsu Silicone, KE-931U) EVA ... Ethylene-vinyl acetate rubber (Sumitomo Chemical, Evatate D-3021) Polyester elastomer (Toyobo, Velprene P-40B) Polyolefin elastomer (Sumitomo Chemical, TPE-1500) (B) Zinc metal filler I : Zinc powder (Sakai Chemical Industry, average particle size 3 μm) II: Zinc surface-coated iron powder (Dowa Iron Powder, average particle size 5 to 7 μm) III: Zinc oxide powder (Sakai Chemical Industry, average particle size 2 μm) Production example Production of modified polyolefin Polypropylene (melt index (MI)) was placed in a 3 L separable flask with an internal volume of 5 l equipped with a stirring blade and a reflux device.
8 g / 10 min, density 0.91 g / cm ³ , trade name J700G, manufactured by Idemitsu Petrochemical Co., Ltd.) 100 parts by weight of terminal hydroxylation 1,4-
Polybutadiene (number average molecular weight 3000, trade name: Poly bd R
45HT, manufactured by ARCO Chem. Div.) 5 parts by weight, maleic anhydride 20
1 part by weight, 1.72 parts by weight of dicumyl peroxide and 600 parts by weight of xylene are charged, and the mixture is heated in an oil bath using a heater and heated at 120 ° C for 1 hour under stirring, then 1
The reaction was continued at 40 ° C for 3 hours. After completion of the reaction, the mixture was cooled, precipitated in a large excess of acetone, suction-filtered, and dried (50 ° C. for 50 hours) to obtain a white powder. The powder is then placed in a Soxhlet extractor and acetone
After extraction for 16 hours, unreacted polybutadiene and maleic anhydride were removed to obtain a modified polyolefin.

Examples 1 to 52 The polymer matrix, the zinc metal-based filler, and the modified polyolefin obtained in the Production Example were used in the proportions shown in Table 1, and these were supplied to a high-speed mixer heated to 180 ° C. and mixed by stirring for 15 minutes. However, the composition is 200-300 ℃ due to heat transfer and stirring heat.
The temperature was raised to gel and kneaded sufficiently. After this kneading, 20
The formulation was cooled to 110 ° C in a low temperature mixer at 0 ° C and stirred until it became a fine mass. The kneaded product obtained was then uniaxial extruder (vented extruder with a diameter of 50 mm, manufactured by Nakatani Machinery, NV
C-50) extruded at a resin temperature of 240-300 ℃, 3φ × 5mm
Pellets were prepared.

The productivity, moldability, retention characteristics and physical properties of the molded product of this pellet were determined and are shown in Table 1.

Examples 53 to 64 Comparative Examples 1 to 16 Pellets were prepared in the same manner as in Examples 1 to 52, using the polymer matrix, the zinc metal-based filler, and the modified polyolefin obtained in the Production Example in the proportions shown in Table 2. Then, the productivity, moldability, retention characteristics and physical properties of the molded product were obtained.

The results are shown in Table 2.

Comparative Examples 17 to 32 Pellets were prepared in the same manner as in Examples 1 to 52 using the polymer matrix, the zinc metal-based filler, and the modified polyolefin obtained in the Production Example in the proportions shown in Table 3, and the productivity was evaluated. , Moldability, retention characteristics and physical properties of molded articles were determined.

The results are shown in Table 3.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Takashi Hashimoto 3-19-25-201, Tsuruse Nishi, Fujimi City, Saitama Prefecture (72) Inventor Takashi Hirai 3-19-25-302, Tsuruse Nishi, Fujimi City, Saitama Prefecture (72) Inventor Hideo Okawa 7-4 Izumi-cho, Higashimatsuyama City, Saitama Prefecture (56) Reference JP-A-57-168938 (JP, A) JP-A-58-63743 (JP, A) JP-A-61-291638 (JP, A)

Claims (1)

[Claims] 1. A) (A) polyethylene resin, polyvinyl chloride resin, polyimide resin, polyester resin, polyacetal resin, polycarbonate resin,
5 to 50 parts by weight of at least one selected from a thermoplastic resin composed of a polyaromatic ether or thioether resin, a polysulfone resin, a styrene resin and an acrylate resin and (b) a polymer elastic body, B) 95 to 50 parts by weight of a zinc metal-based filler, and 1 to 10 parts by weight of (C) modified polyolefin is added to 100 parts by weight of the total of the components (A) and (B). A high specific gravity composite resin composition characterized in that