JPS6363582B2 - - Google Patents

Description

[Detailed description of the invention]

INDUSTRIAL APPLICATION FIELD The present invention relates to a rubber profile for making products such as automobile parts, industrial parts, and industrial parts.
More specifically, (A) chlorinated polyethylene, (B) at least one inorganic filler selected from the group consisting of carbon black, calcium carbonate, synthetic white silicate carbon, barium sulfate, and titanium oxide; (C) A rubber mold material formed by molding a composition consisting of at least one lead-containing inorganic compound selected from the group consisting of lead oxides, hydroxides, and sulfates, (D) a lubricant, and (E) a fluorine-containing organic compound. The purpose is to provide rubber shapes for manufacturing automobile dampers, bumpers, air cleaners, industrial rubber rolls, foams, etc. BACKGROUND ART In various fields such as the automobile industry, there is a strong demand for higher quality and higher performance, and the development thereof is remarkable. As rubber mold materials for making parts in these industries, mold materials such as silicone rubber, RTV silicone rubber, polyurethane liquid rubber, liquid polybutadiene rubber, and Teflon-coated materials are widely used. However, these materials have poor solvent resistance, gasoline resistance, mold releasability, chemical resistance, tear resistance, etc., and therefore, when used for a relatively long period of time, they may swell, crack, or deteriorate. Therefore, by using epichlorohydrin rubber (CHR), fluorine-containing rubber, etc., which have excellent properties, it is possible to obtain an excellent mold material, but it has the disadvantage (problem) of high cost. Problems to be Solved by the Invention From the above, the present invention does not have these drawbacks (problems), that is, it not only has excellent heat resistance, but also has good bending resistance and abrasion resistance. The object of the present invention is to obtain a mold material molded from rubber or a composition thereof that has excellent weather resistance, good mold releasability, good dimensional accuracy, and good molding processability. Means and Effects for Solving the Problems According to the present invention, the problems are solved by: (A) chlorinated polyethylene, (B) carbon black, calcium carbonate, synthetic white silicate carbon, barium sulfate and oxidized at least one inorganic filler selected from the group consisting of titanium; (C) at least one lead-containing inorganic compound selected from the group consisting of lead oxides, hydroxides and sulfates; It consists of (D) a lubricant and (E) a fluorine-containing organic compound, and the composition ratio is 20 to 120 parts by weight of the inorganic filler and 1.0 to 15.0 parts by weight of the lead-containing inorganic compound to 100 parts by weight of chlorinated polyethylene. and the lubricant is 0.5 to 5.0 parts by weight, and the fluorine-containing organic compound is 0.1 to 30 parts by weight. The present invention will be explained in detail below. (A) Chlorinated polyethylene The chlorinated polyethylene used in the present invention can be obtained by chlorinating polyethylene powder or particles in an aqueous suspension or by chlorinating polyethylene dissolved in an organic solvent. (preferably those obtained by chlorination in aqueous suspension). Generally, it is amorphous or crystalline chlorinated polyethylene whose chlorine content is 20 to 50% by weight, especially
25-45% by weight of amorphous chlorinated polyethylene is preferred. The polyethylene is obtained by homopolymerizing ethylene or copolymerizing ethylene with at most 10% by weight of α-olefin (generally having at most 12 carbon atoms). Its density is generally between 0.910 and 0.970 g/cm ³ . Also,
Its molecular weight is 50,000 to 700,000. In producing the composition of the present invention, only chlorinated polyethylene may be used, but other types of polymeric substances that are miscible with chlorinated polyethylene may also be blended. As the polymer substance, ethylene-
Propylene-diene ternary copolymer rubber (EPDM), natural rubber, chloroprene rubber, chlorosulfonated polyethylene rubber, styrene-butadiene copolymer rubber (SBR), acrylonitrile-butadiene copolymer rubber ( Rubber materials such as NBR), urethane-based rubber materials, and butadiene homopolymer rubber materials [generally,
Mooney viscosity (ML ₁₊₄ ) is 10 to 150]. In addition, other polymeric substances include the above-mentioned polyethylene, vinyl chloride resin containing vinyl chloride as the main component (degree of polymerization, 400-1800), methyl methacrylate resin containing methyl methacrylate as the main component, and acrylonitrile-styrene copolymer resin. Examples include resin-like substances such as. Regarding these rubber-like and resin-like materials, please refer to "Synthetic Rubber Handbook" edited by Kambara et al. (Asakura Shoten, published in 1962) and "Plastic Handbook" edited by Murahashi et al.
(published in 1964), etc., is well known. When blending these polymeric substances, the blending ratio is at most 50 parts by weight per 100 parts by weight of chlorinated polyethylene. (B) Inorganic filler The inorganic filler used in the present invention is carbon black, synthetic silicate white carbon, barium sulfate, and titanium oxide. The specific surface area of carbon black is generally measured by low-temperature nitrogen adsorption method and BET method.
20~ ^1800m2 /g and pore volume is 30~
1.5 measured by mercury intrusion method in the range of 7500 Å
~4.0cc/g, especially the specific surface area is 600~1200
m ² /g is effective. Examples of the carbon black include channel black, thermal black, acetylene black, and carbon black produced by the furnace black method. Regarding these carbon blacks, please refer to the Carbon Black Association (edited by Carbon Black Association) (Tosho Publishing Co., Ltd., published in 1972), Rubber Digest Co. (edited), “Handbook of Rubber Black”.
“Plastic compounded chemicals” (Rubber Digest Co., Ltd.,
Published in 1971), the above-mentioned “Synthetic Rubber Handbook”
Their manufacturing methods and physical properties are well known. Furthermore, as calcium carbonate, the average particle size is 1
Millimicrons to 10 microns are desirable. In addition, synthetic silicate white carbon generally has an average particle size of 18 mm or less.
0.5 micron is preferred. Further, it is desirable that the specific surface area is 30 to 100 m ² /g, particularly preferably 30 to 80 ^{m 2} /g. Further, the density is usually 2.0 to 2.5 g/cm ³ . Among the synthetic silicate-based white carbons, calcium salts of silicic acid (including those containing water of crystallization) are preferably used. Furthermore, barium sulfate generally includes barite powder obtained by crushing naturally produced barite and sedimentary barium sulfate, and those with an average particle size of 0.2 to 5 microns are preferred, and those with an average particle size of 0.5 to 3 microns are particularly preferred. is suitable. Further, titanium oxide is usually classified into rutile type and anatase type, and those having an average particle size of 0.2 to 0.5 micron are desirable, and those of 0.3 to 0.45 micron are particularly preferred. These inorganic fillers are described in "Handbook, Rubber/Plastic Compounded Chemicals" edited by Rubber Digest Co., Ltd. (Rubber Digest Co., Ltd., published in 1971), No. 213 to 213.
Physical properties, product names, etc. are described in detail on pages 256 and 378. (C) Lead-containing inorganic compound Furthermore, the lead-containing inorganic compound used in the present invention is selected from lead oxides, hydroxides, sulfates, and double salts thereof. The lead oxide preferably has an average particle size of 0.3 to 3.0 microns, particularly preferably 0.5 to 2.0 microns. Moreover, the density is generally 8.3 to 9.5 g/cm ³ . Representative examples of this lead oxide include lead monoxide (PbO) and trilead tetraoxide (Pb ₃ O ₄ ). In addition, as lead hydroxide, the average particle size is
Preferably 0.5 to 5.0 microns, especially 0.9
~2.5 microns are preferred. A typical example is lead white [2PbCO ₃ Pb(OH) ₂ ]. Furthermore, it is desirable that the lead sulfate has an average particle size of 0.5 to 5.0 microns, especially 0.5 microns.
~2.5 microns are preferred. A typical example is tribasic lead sulfate (3PbO・_PbSO4・
H ₂ O) and basic lead sulfate (nPbO・PbSO ₃ )
can be given. Regarding these lead-containing mechanical compounds, please refer to the above-mentioned "Handbook, Rubber and Plastic Compounded Chemicals", pages 226 to 270, and "Practical Handbook of Additives for Plastics and Rubber" edited by Kagaku Kogyo Sha (Kagaku Kogyo Sha, Showa).
Physical properties etc. are described on pages 146 to 279 (published in 1942). (D) Lubricant The lubricant used in the present invention is one that is generally widely used as a lubricant (sleep agent) in the rubber industry and the synthetic resin industry. Typical examples include paraffins and hydrocarbon resins, fatty acid amides, fatty acid ketones, partial esters of fatty acids and polyhydric alcohols, fatty acids, fatty acid esters, and fatty acid alcohols. These lubricants are described on pages 303 to 319 of the above-mentioned "Handbook of Chemicals for Rubber and Plastic Compounds." Among these lubricants, paraffins, hydrocarbon resins and fatty acids are preferred, and paraffins are particularly preferred. Among them,
Paraffin waxes, paraffin-based synthetic waxes, and mixtures of natural waxes and synthetic waxes are suitable. (E) Fluorine-containing organic compound Furthermore, the boiling point of the fluorine-containing organic compound used in the present invention is usually 200°C or higher, preferably 230°C or higher, and particularly preferably 250°C or higher. Further, those having a melting point of 80°C or lower are preferred, and those with a melting point of 50°C or lower are particularly preferred.
When using a fluorine-containing organic compound with a boiling point of less than 200℃,
It is undesirable because it volatilizes during kneading and molding described later. Furthermore, if a material with a melting point exceeding 80° C. is used, a homogeneous mixture cannot be obtained during kneading. Typical examples include fluorinated acrylates, perfluoroalkylamine compounds, perfluoroalkyl betaines, perfluoroalkyl quaternary ammonium salts, perfluoroalkyl ethylene oxide adducts, fluorine-containing alcohols, and fluorine-containing carboxylic acids that have the above physical properties. can be given. (F) Composition ratio The composition ratio of the inorganic filler, lead-containing inorganic compound, lubricant, and fluorine-containing organic compound to 100 parts by weight of chlorinated polyethylene is as follows. For inorganic fillers, it is 20-120 parts by weight, and 25-120 parts by weight.
120 parts by weight is desirable, particularly 30 to 110 parts by weight. If it is less than 20 parts by weight, it is not possible to obtain a mold material with excellent wear resistance and oil resistance. On the other hand, if the amount exceeds 120 parts by weight, moldability will be poor. For lead-containing inorganic compounds, the amount is 1.0 to 15.0 parts by weight, preferably 2.0 to 15.0 parts by weight, particularly 2.0 parts by weight.
~10.0 parts by weight is preferred. Less than 1.0 part by weight,
Poor chemical resistance. On the other hand, if it exceeds 15.0 parts by weight, moldability is poor. Furthermore, for lubricants, it is 0.5 to 5.0 parts by weight, and 1.0
~5.0 parts by weight is desirable, and 1.0 to 4.0 parts by weight is particularly preferred. If it is less than 0.5 part by weight, there is a problem due to poor mold releasability. On the other hand, if more than 5.0 parts by weight is added, the resulting product not only bleeds severely, but also slips violently during rolling operations, resulting in problems in workability. For fluorine-containing organic compounds, the amount is 0.1 to 30 parts by weight, preferably 0.2 to 30 parts by weight, particularly 0.5 to 30 parts by weight.
30 parts by weight is preferred. If it is less than 0.1 part by weight, a product with good mold releasability cannot be obtained. On the other hand, if more than 30 parts by weight is blended, the mold release property is good, but the compatibility with chlorinated polyethylene is poor, and furthermore, it is difficult to knead in roll operations, etc., resulting in problems in terms of workability. (G) Mixing method, molding method, etc. Although the composition of the present invention can be obtained by uniformly blending the above substances, fillers and plasticizers commonly used in the rubber and resin industries are also added. Additives such as oxygen, ozone, heat and light (ultraviolet) stabilizers, and colorants may be added depending on the intended use of the composition. In addition, when molding the mold material of the present invention to produce each mold, a crosslinking agent such as an organic peroxide or a crosslinking agent and a crosslinking aid are blended into the above-mentioned composition and crosslinked. Among the organic peroxides used as crosslinking agents, those with a decomposition temperature (temperature at which the half-life is 1 minute) of 120°C or higher are desirable, and those with a decomposition temperature of 140°C or higher are particularly preferred. These organic peroxides and crosslinking auxiliaries are widely used in the rubber industry, and are described, for example, in the above-mentioned "Handbook, Rubber and Plastic Compounding Chemicals".
This is well known from pages 10 to 13 of . The proportion of the organic peroxide to 100 parts by weight is usually at most 10 parts by weight (preferably 7.0 parts by weight or less, preferably 0.5 to 7.0 parts by weight). Further, when a crosslinking aid is added, it is generally at most 10 parts by weight (preferably 5.0 parts by weight or less). When producing the composition of the present invention, the blending (mixing) method may be to use a mixer commonly used in the art, such as an open roll, dry blender, Banbury mixer, or kneader. Among these mixing methods, in order to obtain a more uniform composition, two or more of these mixing methods may be applied (for example,
A method in which the mixture is mixed in advance with a dry blender and then mixed using an open roll). The composition of the present invention may be molded into a dust seal using molding machines commonly used in the rubber industry, such as extrusion molding machines, injection molding machines, compression molding machines, and calender molding machines. In addition, a method of manufacturing molded products while crosslinking by adding chlorinated polyethylene or the above-mentioned composition and crosslinking, which is commonly used in the rubber technology field, that is, a method of simultaneously proceeding crosslinking and molding, can be applied to form a product into a desired shape. It may be molded into a desired shape using a molding machine used for molding, such as an extrusion molding machine, an injection molding machine, a compression molding machine, or a calendar molding machine. Also,
By adding chlorinated polyethylene or the above-mentioned composition and manufacturing a molded product while crosslinking, which is generally used in the rubber technology field, i.e., a method in which crosslinking and molding proceed simultaneously, the product is molded into a desired shape. You can. EXAMPLES AND COMPARATIVE EXAMPLES The present invention will now be described in more detail with reference to Examples. In addition, in Examples and Comparative Examples, gasoline resistance was determined by leaving the test piece in gasoline for 24 hours in a constant temperature room set at a temperature of 23°C, and measuring the rate of volume change (hereinafter referred to as "△V"). . In addition, the tensile test measures tensile strength (hereinafter referred to as "T _B "), elongation rate (hereinafter referred to as "E _B "), and hardness (hereinafter referred to as " _HS ").
was measured using a Schoper tester. moreover,
Tear strength test was conducted according to JIS K-6301 using JIS B dumbbells to determine tear strength (hereinafter referred to as "T _R ").
was measured. In addition, for chemical resistance, Freon 22, 50% nitric acid and 15
% of caustic soda for 24 hours, the volume change rate (△
V) was measured. The types and physical properties of each of the chlorinated polyethylene, inorganic filler, lead-containing inorganic compound, lubricant, fluorine-containing organic compound, organic peroxide, and plasticizer used in Examples and Comparative Examples are shown below. [(A) Chlorinated polyethylene] As chlorinated polyethylene, the density is 0.935g/
cm ² (average molecular weight approximately 25
Chlorinated polyethylene (chlorine content: 35.0% by weight, amorphous, hereinafter referred to as ``CPE'') obtained by chlorinating 10,000 yen) with an aqueous suspension was used. [(B) Inorganic filler] Furnace black (manufactured by Showa Cabot Co., Ltd., trade name Showa Black, average particle size 51 nm, specific surface area 41 m <sup>2</sup> /g, hereinafter referred to as "CB-") was used as an inorganic filler.
1), Furnace Black (manufactured by Asahi Carbon Co., Ltd., trade name, Asahi Thermal, average particle size 118 nm,
Specific surface area 19m <sup>2</sup> /g, hereinafter referred to as "CB-2")
and calcium carbonate (average particle size 1.7 microns,
(hereinafter referred to as "CaCO <sub>3</sub> ") was used. [(C) Lead-containing inorganic compound] As the lead-containing inorganic compound, tribasic lead sulfate (density about 7.0 g/cm <sup>3</sup> , average particle size 2.0 microns, hereinafter referred to as "tribase") was used. [(D) Lubricant] As a lubricant, paraffin wax (melting point 63
℃ (hereinafter referred to as ``wax'') was used. [(E) Fluorine-containing organic compound] As the fluorine-containing organic compound, fluorinated acrylate (hereinafter referred to as "FA") and perfluoroalkylamine compound (manufactured by Daikin Industries, Ltd., trade name Unidyne DS-201, specific gravity 1.04, hereinafter referred to as " FB) was used. [(F) Organic peroxide and crosslinking aid] Dicumyl peroxide (hereinafter referred to as "DCP") is used as the organic peroxide, and triallylisocyanurate (hereinafter referred to as "TAIC") is used as the crosslinking aid. Each was used. [(G) Plasticizer] Trioctyl trimellitate (hereinafter referred to as "TOTM") was used as a plasticizer. Examples 1 to 6, Comparative Examples 1 to 4 100 parts by weight of CPE, 30 parts by weight of TOTM, 3.0 parts by weight of wax, and 10 parts by weight of tribase (in Comparative Examples 1 and 3, no tribase was added) In addition, inorganic fillers, fluorine-containing organic compounds, organic peroxides, and crosslinking aids whose types and amounts are shown in Table 1 are heated at room temperature (approximately 20
The sheet was formed using oven rolls for 20 minutes while kneading at 100°C. Each sheet thus obtained was heated to a temperature of 160°C.
℃ and pressure of 200 kg/cm ² for 30 minutes to form a rubber mold (width 25 cm, length 15 cm, width 5 cm,
10mm thick). The obtained rubber mold was subjected to a gasoline resistance test, a chemical resistance test, a tear test, and a tensile test. The tear test and the tensile test were conducted by buffing the surface of each rubber mold to create dumbbells with a thickness of 2 mm.
The results are shown in Table 2.

【table】

【table】

[Table] Note that in Comparative Examples 1 and 3, dehydrochlorination occurred and it was not possible to produce a rubber mold. From the results of the above Examples and Comparative Examples, the rubber profile obtained by the present invention not only has excellent resistance to strong acids, strong alkalis, and fluorocarbon resistance, but also has good gasoline resistance. Furthermore, it is clear that the mechanical properties such as tensile strength and tear strength are also excellent. Effects of the Invention The mold material of the chlorinated polyethylene composition obtained by the present invention can not only be manufactured at low cost, but also exhibits the following effects (characteristics). (1) Excellent weather resistance. (2) Good wear resistance. (3) Excellent flexibility. (4) Good oil resistance (aromatake oil, aliphatake oil). (5) Excellent flexibility and cold resistance. (6) Good dimensional accuracy. (7) Not only does it have good molding processability, but it also has a low shrinkage rate during molding. (8) Low compression set. (9) Good mold releasability. (10) Excellent chemical resistance (especially acid resistance), which is the most characteristic feature of the present invention. For example, if the concentration
It can withstand over 50% nitric acid. The mold material of the chlorinated polyethylene composition obtained according to the present invention can be used for dampers, bumpers, headlights, etc. in order to exhibit the above-mentioned excellent effects.
It is promising as a mold material for manufacturing automobile parts such as foam packing for stock lamps, parts for home appliances, toner rollers, printable rolls and printed circuit boards, parts for electronic devices, and other industrial parts.

Claims (1)

[Claims] 1 (A) Chlorinated polyethylene, (B) carbon black, calcium carbonate, synthetic silicate white carbon, calcium carbonate,
at least one inorganic filler selected from the group consisting of barium sulfate and titanium oxide; (C) at least one lead-containing inorganic compound selected from the group consisting of lead oxides, hydroxides and sulfates; (D ) A lubricant and (E) a fluorine-containing organic compound, and the composition ratio is 20 to 120 parts by weight of the inorganic filler and 1.0 to 15.0 parts by weight of the lead-containing inorganic compound to 100 parts by weight of chlorinated polyethylene. , and the lubricant is 0.5 to 5.0 parts by weight, and the fluorine-containing organic compound is 0.1 to 30 parts by weight.