JPS59223735A - Conductive resin composition - Google Patents

Abstract

PURPOSE:An electroconductive resin composition excellent in mechanical strength, rigidity and electric conductivity, and suitable for use as a conductive material of high-voltage cables, obtained by mixing a thermoplastic resin with a metal and a silane coupling agent at a specified weight ratio. CONSTITUTION:The purpose electroconductive resin composition is prepared by mixing 5-95wt% (A) thermoplastic resin such as polyethylene or polypropylene with 95-5wt% (B) metal, e.g., aluminum or copper, in the form of powder, fiber, flake, or the like, and 0.05-5pts.wt., per 100pts.wt. total of components A and B, silane coupling agent, e.g., vinyltrimethoxysilane or gamma-aminopropyltriethoxysilane. A more marked effect can be obtained with a smaller amount of the silane coupling agent by pretreating the metal with the silane coupling agent and adding the treated metal to the thermoplastic resin.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a conductive resin composition. More specifically, the present invention relates to a conductive resin composition with improved rigidity that includes a metal treated with a silane coupling agent.

It is well known that metals such as aluminum flakes are added to thermoplastic FJ resins to impart electrical conductivity. The conductive resin is the conductive material for high voltage cables, XC-+
It is widely used as an electromagnetic wave shielding material for microwave ovens 15 communication equipment, a conductive material for video discs, etc.

However, thermoplastic resins, such as polyolefins such as polyethylene and polypropylene, as well as general-purpose resins such as polyamides and polyesters, are originally materials with excellent insulation properties, and in order to impart conductivity to them, it is necessary to blend a large amount of metal. As a result, there is a risk that the mechanical properties such as rigidity, which are the original characteristics of the resin, may deteriorate.

Under such circumstances, the present inventor conducted various studies in order to obtain a resin composition with excellent conductivity, which has the disadvantages of the conventional ones.As a result, the present inventor developed a metal or silane-based coupling in which a thermoplastic resin is treated with a silane-based coupling agent. The present invention was achieved based on the discovery that a conductive resin composition with excellent rigidity can be obtained by adding an agent and a metal.

That is, the present invention provides thermoplastic resin (~: 5 to 95% by weight - metal (d: +; +5 to 5% by weight) and (~10 (
1 = 100 parts by weight of silane coupling agent (C
): 0.05 to 5 parts by weight to provide a conductive resin composition having excellent mechanical strength and rigidity.

Thermoplastic resins used in the present invention (~ are resins that exhibit plasticity, regardless of whether they are crystalline or non-crystalline); low-density polyethylene, high-density polyethylene, polypropylene, poly-1-butene, poly-4-methyl-1 - Polyolefins such as random or block copolymers of α-olefins such as pentenal or ethylene, propylene, 1-butene, 4-methyl-1-pentene, ethylene/acrylic acid copolymers, ethylene/vinyl acetate copolymers ethylene/vinyl compound copolymers such as ethylene/vinyl alcohol copolymers, ethylene/vinyl chloride copolymers, polystyrene,
Acrylonitrile ° styrene copolymer, AB S %
Styrenic resins such as methyl methacrylate/styrene copolymer, α-methylstyrene/styrene copolymer, polyvinyl chloride, polyvinylidene chloride, vinyl chloride/vinylidene chloride copolymer, polymethyl acrylate, polymethacrylate Polyvinyl compounds such as methyl acid, nylon 6, nylon 6-6, nylon 6-10. Polyamides such as nylon 11 and nylon 12, polyamide phthalate,
Any resin such as thermoplastic polyester such as polybutylene terephthalate, polycarbonate, polyphenylene oxide, etc. may be used.

The silane coupling agent (C) used in the present invention is an organic silane compound having an olefinic unsaturated bond, an amino group, a hydroxyl group, or a hydroxyalkyl group, and specifically, vinyltrimethoxysilane, vinyltriethoxysilane, etc. silane,
Vinyltris(methoxyethoxy)silane, vinylmethyljethoxysilane phenyldimethoxysilane propyltrimethoxysilane, β-aminophenoxydimethylvinylsilane, r-aminopropyltriethoxysilane, r-aminopropyldimethyfurethoxysilane, triethylsilanol, dimethylethoxy silane, r
-Glycidoxyprobyltrimethylsilane and the like can be exemplified. Among them, vinyltris(methoxyethoxy)silane, r-methacryloxypropyltrimethoxysilane, γ-aminopropyltriethoxysilane, γ-glycidoxypropyltrimethoxysilane, etc. have a boiling point of 20
An organic silane compound having a temperature of 0°C or higher is preferable because it has an excellent effect of improving mechanical strength and rigidity.

Metals CB) used in the present invention include aluminum, iron, copper,
Nickel or alloys thereof such as stainless steel, brass, bronze, etc., are usually in the form of powders, fibers, or flakes, and have a form that can be mixed as a filler in resins and the like. Powder-like materials usually range from 20 to 250 meshes, and fibrous materials usually have a diameter of 0.001 mm.
Or Q. Items with a length of 10 mm or less within a range of 2 mm,
The cross-sectional area of flakes is usually 0. Any shape such as circular, square, rectangular, hexagonal, etc. in the range of IXOlmm to 5X5mm and a thickness of 3.1 ROM or less can be suitably used.

The conductive resin composition of the present invention comprises the thermoplastic resin (A)
: 5 to 95% by weight, preferably 5G to 75% by weight, Metal (B): 95 to 5% by weight, preferably 50
to 25% by weight and (Al + (B) = + O
0.05 to 5 parts by weight, preferably 0.5 parts by weight of the silane coupling agent. 2 parts by weight.

If the amount of metal (B) is less than 5% by weight, there will be no effect of improving conductivity, and if it exceeds 5% by weight, the fluidity during melting will be poor, the moldability will be poor, and the mechanical strength of the molded product will decrease. descend.

The amount of silane coupling agent (C) is 0-05ffif
If it is less than fi part, the mechanical strength and rigidity of the composition will not be improved, and if it exceeds 5 parts by weight, the effect will be saturated.

In addition to the above-mentioned components, the conductive resin composition of the present invention includes:
Heat stabilizer, weather stabilizer, nucleating agent, plasticizer, 'III retardant, talc, calcium carbonate, mica, finely powdered silica,
barium sulfate, wollastonite, clay, kaolin,
Inorganic fillers such as graphite and potassium titanate whiskers, pigments, dyes, and other compounding agents that are normally added to thermoplastic resins may be included within the range that does not impair the purpose of the present invention.

To produce the conductive resin composition of the present invention, metal (
A method of treating shun with a silane coupling agent (C) and then adding it to a thermoplastic resin (→), or a method of adding a thermoplastic resin (
Although it is possible to simultaneously mix A) with the metal (B) and the silane coupling agent (C), the former method is preferable in that it can increase the effect by reducing the amount of the silane coupling agent (C) added. The method is preferred.

The former method involves, for example, adding a silane coupling agent (C) or a silane coupling agent (C) dissolved in a solvent to the metal (2) without stirring the metal (2) using a Henschel mixer. and the silane coupling agent (C) are simultaneously mixed and stirred to adhere the silane coupling agent to the metal surface, dried if necessary, and then mixed with the thermoplastic resin (~ and the Henschel mixer again,
(2) - Mixing with a blender, tumbler blender, ribbon blender, etc., followed by kneading with a Banbury mixer, Nigoo, Rho IV, single tdJn extruder, multi-screw extruder, etc., followed by pulverization or granulation can be exemplified.

In the latter method, thermoplastic resin (A), metal (
An example of a method is to mix the mixture with the silane coupling agent (C) using a Henschel mixer, a -blender, a tumbler blender, a ribbon blender, etc., knead in the same manner as described above, and then pulverize or granulate.

The conductive resin composition of the present invention has conductivity, excellent mechanical strength and rigidity, and good moldability. It can be suitably used for applications that require electromagnetic shielding properties, such as exterior walls, interior materials, housing materials for televisions, HDTVs, electronic computers, word processors, etc., automobile electronic devices, and equipment.

Next, the present invention will be explained in more detail with reference to Examples.

Example 1 Polypropylene (trade name Mitsui Petrochemical Polypro SJ
a+oD>aFa: 15g/10ml 0% by weight of Powder F (manufactured by Mitsui Petrochemical Industries, Ltd.) and Bi1; Nyltriethoxysilane (boiling point 161°C): 0.3
Aluminum flakes treated in parts by weight (manufactured by Transmet): 60% by weight were mixed in a Henschel mixer and then melt-kneaded and granulated in a 40 mmφ extruder (resin temperature 250°C) to obtain composition -1. Using composition-■,
Injection molding machine (Is-50 manufactured by Toshiba Machine Co., Ltd.: Molding temperature 2
A test piece was obtained by injection molding at 60°C.

The test pieces were evaluated in the following manner.

Tensile test: ASTM D638 Bending test: ASTM D790 Izod impact test: ASTM D256, notched volume resistivity test: Resistance meter (manufactured by Takeda Riken Co., Ltd.).

TR-6856), the resistance of a sheet with a thickness of 2 mm was measured in an atmosphere of 25° C. and 60% humidity, and calculated according to the formula below.

XR Volume resistivity (Ω・CTn) -- Here, S: electrode area of specific resistivity measuring electrode R: Sheet resistance value (Ω) t: sheet thickness cln) represents.

The results are shown in Table 1.

Example 2 Vinyltris(methoxyethoxy)silane (boiling point 285
The same procedure as in Example 1 was carried out except that the temperature (°C) was used. The results are shown in Table 1.

Example 3 The same procedure as in Example 1 was carried out except that γ-methacryloxypropyltrimethoxysilane (boiling point 255"C) was used instead of the vinyltriethoxysilane used in Example 1.

The results are shown in Table 1.

Example 4 In place of the vinyltriethoxysilane used in Example 1, r-aminopropyltriethoxysilane (boiling point 217°
The same procedure as in Example 1 was carried out except that C) was used. The results are shown in Table 1.

Comparative Example 1 The same procedure as in Example 1 was conducted except that untreated aluminum flakes were used instead of the aluminum flakes treated with vinyltriethoxysilane used in Example 1. The results are shown in Table 1.

Comparative Example 2 Isopropyltridecylbenzenesulfonyl titanate was used instead of vinyltriethoxysilane used in Example 1.

Claims (1)

[Claims] (1) Thermoplastic resin (~: 5 to 95% by weight, metal C
B): 95 to 5% by weight and (A)+(B)=100
Silane coupling agent (C) = 0.0 based on weight part
5 to 5 parts by weight of a conductive resin composition.