JPS6254748A - Rubber section - Google Patents

Abstract

PURPOSE:To provide a rubber section which is inexpensive and has low compression set and excellent flexibility, moldability, dimensional stability, resistance to weather, wear, oils and cold, etc., consisting of a chlorinated PE, an inorg. filler, a lead-contg. inorg. compd., a lubricant and a fluorine-contg. org. compd. CONSTITUTION:100pts.wt. (non-) crystalline chlorinated PE (A) having a chlorine content of 20-50wt% is blended with 20-120pts.wt. inorg. filler (B) selected from among carbon black having a specific surface area of 20-1,800m<2>/g and a pore volume of 1.5-4.0cc/g (according to mercury porosimetry in the range of a pore radius of 30-7,500Angstrom ), CaCO3 having an average particle size of 1-10mu, synthetic silicate white carbon having an average particle size of 18mmu-0.5mu and a specific surface area of 30-100m<2>/g, BaSO4 having an average particle size of 0.5-5mu and TiO2 having an average particle size of 0.2-0.5mu, 1.0-15.0pts.wt. lead-contg. inorg. compd. (C) selected from among lead oxide having an average particle size of 0.3-3.0mu, lead hydroxide having an average particle size of 0.5-5.0mu and lead sulfate having an average particle size of 0.5-5.0mu, 0.5-5.0pts.wt. lubricant (D) such as paraffin wax and 0.1-30pts.wt. fluorine-contg. org. compd. (E) having a b.p. of 200 deg.C or above and a m.p. of 80 deg.C or below.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a rubber profile for producing 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 silicate white carbon, barium sulfate and titanium oxide;
) 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.

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. Silicone rubber, RTV, etc. are used as rubber mold materials to make parts for these industries. Mold materials such as silicone rubber, polyurethane liquid rubber, liquid polybutadiene rubber, and Teflon-coated materials are widely used. However, these materials are inferior in solvent resistance, gasoline resistance, mold releasability, chemical resistance, tear resistance, etc., and therefore, when used for a relatively long period of time, swelling, cracking, and deterioration occur. Therefore, epichlorohydrin rubber (C:I(R
), fluorine-containing rubber, etc., can provide an excellent shape material, but has the disadvantage of high cost (gfi).

From the above, the present invention does not have these drawbacks (problems); in other words, it not only has excellent heat resistance, but also has good bending resistance and abrasion resistance, and is also resistant to #climate. The object of the present invention is to obtain a mold material molded from rubber or a composition thereof that has excellent properties, good mold release properties, good dimensional accuracy, and good moldability.

According to the present invention, the above-mentioned problems are solved by: CA) 11A hydrogenated polyethylene, (B) carbon black, calcium carbonate, synthetic silicate white 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; (D) a lubricant; and (D) a lubricant; E) Consisting of a fluorine-containing organic compound, the composition ratio of ioo heavy H parts to chlorinated polyethylene 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. ,
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 is obtained by preparing polyethylene powder or particles in an aqueous suspension. or by chlorination of polyethylene dissolved in an organic solvent (preferably by chlorination in an aqueous suspension);
Generally, amorphous or crystalline chlorinated polyethylene with a chlorine content of 20 to 50% by weight is used, and amorphous chlorinated polyethylene with a chlorine content of 25 to 45% by weight is particularly preferred.

Said 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 0.91
0-0.970 g/cm", and its molecular weight is 50,000-700,000.

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. Ethylene-propylene-diene ternary copolymer rubber (EPDM), natural comb, chloroprene rubber, chlorosulfonated polyethylene rubber, styrene-butadiene copolymer rubber (SBR), acrylonitrile-butadiene copolymer rubber (NOR), urethane rubbers and butadiene homopolymer rubbers [generally Mooney viscosity (ML1+,)
10~150]. In addition, other polymeric substances include the above-mentioned polyethylene, vinyl chloride resin containing vinyl chloride as a main component (degree of polymerization, 400-1800),
Examples include resinous materials such as methyl methacrylate resins containing methyl methacrylate as a main component and acrylonitrile-styrene copolymer resins. These rubber-like and resin-like substances are described in "Synthetic Rubber Handbook" edited by Kambara et al. (Breakfast Shoten, published in 1962), "Plastic Handbook" edited by Shitachi et al. (Breakfast Shoten, published in 1960), etc. It is well known.

When these polymeric substances are blended, the blending ratio is at most 50 parts by weight per 100 parts by weight of chlorinated polyethylene.

(B) Inorganic filler The inorganic fillers used in the present invention are carbon black, synthetic silicate white carbon, barium sulfate, and titanium oxide.

Carbon black generally has a specific surface area of 20 to 1800 as measured by low temperature nitrogen adsorption method and BET method.
rn'/g and pore volume are pore radius 30-7500
Measured using mercury intrusion method over a large area! , 5-4.
0 cc/g Te, especially with a specific surface area of 1300-1
200 m''/g is effective.

Examples of the carbon black include channel black, thermal black, acetylene black, and carbon black produced by a furnace black method. Regarding these carbon blacks, please refer to the Carbon Black Association's ``Carbon Black Handbook'' (Tosho Publishing, published in 1972) and the Rubber Digest Company's ``Handbook of Rubber and Plastic Compounded Chemicals'' (Rubber Digest, published in 1972). ), their manufacturing methods and physical properties are well known from the above-mentioned "Synthetic Rubber Handbook" and the like.

Furthermore, calcium carbonate preferably has an average particle size of 1 millimicron to 10 microns.

In addition, as synthetic silicate white carbon, it is generally preferable to have an average particle size of 18 mm to 0.5 microns, and furthermore, a specific surface area of 30 to 10 μm.
0rn”/which is preferable, especially 30 to 80n
1"/g is preferable. Also, the density is usually 2.0
˜2.5 g/cm”, among the synthetic silicate-based white carbons, calcium silicate 1j! (including those containing water of crystallization) is preferably used.

Furthermore, barium sulfate generally includes palite powder obtained by crushing naturally produced barite and sedimentary barium sulfate.
Those having an average particle size of 0.2 to 5 microns are preferred, and those of 0.5 to 3 microns are particularly preferred.

Further, titanium oxide usually includes 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 listed in Rubber Digest's Handbook,
Physical properties, product names, etc. are described in detail in "Rubber/Plastic Compounded Chemicals"(U/<-Digest Publishing, published in 1972), pages 213 to 256 and pages 378.

(C) Lead-containing inorganic compound (5) The lead-containing inorganic compound used in the present invention is selected from lead oxides, hydroxides, sulfates, and double salts thereof. As a lead oxide, the average particle size is 0.
．． 3 to 3.0 microns is preferred, especially 0.5 microns.
~2.0 microns are preferred. Further, the density is generally 8.3 to 9.5 g/cm'. A typical example of this lead oxide is:

-・Lead oxide (PbO) and trilead tetraoxide (PbQO, )
The lead hydroxide preferably has an average particle size of 0.5 to 5.0 microns, particularly 0.8 to 2.5 microns. Typical examples include lead white (2PbCO/Pb(OH)2), and lead sulfate with an average particle size of 0.5 to 5.0 microns is desirable, especially 0. .5 to 2.5 microns are preferred. A typical example is tribasic lead sulfate (3PbO-Pb5O, -
H2O) and basic lead sulfate (nPbO・PbS03
) can be given.

Regarding these lead-containing inorganic compounds, see the above-mentioned “Handbook”,
Rubber/Plastic Compound Chemicals” pages 266 to 27
Page 0 and Seigaku Kogyosha Line "Practical Handbook of Additives for Plasti-2 and Rubber" (Kagaku Kogyosha).

Physical properties and the like are described on pages 148 to 278 (published in 1962).

(D) Lubricants Also, the lubricants used in the present invention are generally widely used as lubricants (sleeve 811) in the rubber industry and synthetic resin industry - typical examples include paraffins and hydrocarbon resins. It is classified into 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, Rubber/Plastic Compounded Chemicals." Among these lubricants, paraffins, hydrocarbon resins, and fatty acids are preferred, and paraffins are particularly preferred. Among these, paraffin wax, paraffin-based synthetic wax, and a mixture of natural wax and synthetic wax are preferable.

(E) Fluorine-containing organic compound (1) 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. Boiling point is 200℃
If the amount of the fluorine-containing organic compound is less than 1, it is not preferable because of the crosstalk described later and volatilization during molding. moreover,
If a material with a melting point exceeding 80° C. is used, a homogeneous mixture cannot be obtained during kneading. As a representative example.

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 physical properties further north.

(F) Composition ratio The composition ratios of the inorganic filler, lead-containing inorganic compound, lubricant, and fluorine-containing organic compound to 100 parts by weight of chlorinated polyethylene are as follows.

For inorganic fillers, it is 20 to 120 parts by weight, and 25 to 1
20 parts by weight is desirable, and 30 to 110 parts by weight is especially suitable. 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.

In the case of a lead-containing inorganic compound, the amount is 1.0 to 15.0 parts by weight, preferably 2.0 to 15.0 parts by weight, and particularly preferably 2.0 to 1090 parts by weight. If it is less than 1.0 parts by weight, chemical properties are poor, while if it exceeds 15.0 parts by weight, moldability is poor.

Furthermore, in the case of a lubricant, it is 0.5 to 5.0 parts by weight.

A portion of 1.0 to 5.0 is preferable, especially 1.0 to 5.0. Q~
4.0 parts by weight is preferred. Less than 0.5 parts 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.

In addition, for fluorine-containing organic compounds, 0.1 to 301CLi
1 part, preferably 0.2 to 30 parts by weight, especially 0
．． 5 to 30 parts by weight is suitable. If it is less than 0.1 part by weight, a product with good mold release properties cannot be obtained, while if it exceeds 30 parts by weight, the mold release properties are good, but the compatibility with chlorinated polyethylene is poor, and It is difficult to mix wires during roll work, etc., and there is a problem 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-mentioned substances, it is possible to obtain the composition of the present invention by uniformly blending the above-mentioned substances.
Additives such as agents, 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.

One of the organic peroxides used as crosslinking agents has a decomposition temperature (
The temperature at which the half-life is 1 minute) is preferably 120°C or higher, particularly preferably 140°C or higher.

These organic peroxides and crosslinking aids are widely used in the rubber industry, and are well known, for example, from pages 10 to 13 of the above-mentioned Handbook of Rubber and Plastic Compounding Chemicals. It is.

The blending ratio for 100 parts by weight of organic peroxide is:
Usually at most 10 parts by weight (preferably 7.0 fJ!).

(0.5 to 7.0 parts by weight, preferably 0.5 to 7.0 parts by weight).

When a crosslinking aid is added, it is generally at most 10 parts by weight (preferably 5.01 parts by weight).

When producing the composition of the present invention, the blending (mixing) method is as follows: Mixing may be carried out using a mixer such as an open roll, a dry blender, a Banbury mixer, or a Negoo mixer commonly used in the art. Of these mixing methods, in order to obtain a more uniform composition, two or more of these mixing methods may be applied (for example, after mixing with a dry blender, the mixture may be mixed with an open roll). method of mixing).

The composition of the present invention may be molded into a dust seal using molding machines such as extrusion molding machines, injection molding machines, compression molding machines, and calender molding machines that are commonly used in the general rubber industry. A method of manufacturing molded products while crosslinking by adding polyethylene or the above-mentioned composition, which is generally used in the rubber technology field, that is, a method of proceeding with crosslinking and molding at the same time, is applied to form the product into a desired shape and use. It may be molded into a desired shape using a molding machine such as an extrusion molding machine, an injection molding machine, a compression molding machine, or a calendar molding machine. In the rubber technology field, a method of manufacturing a molded product while crosslinking, ie, a method of simultaneously proceeding crosslinking and molding, may be applied to mold the product into a desired shape.

The present invention will now be explained and explained in more detail with reference to Examples.

In addition, in the examples and comparative examples, #gasoline property is 2.
The test piece was left in gasoline for 24 hours in a constant temperature room set at a temperature of 3° C., and the rate of change in volume (hereinafter referred to as “ΔV”) was measured. Further, in the tensile test, tensile strength (hereinafter referred to as "TB"), elongation rate (hereinafter referred to as r EBJ ), and hardness (hereinafter referred to as "HS") were measured using a Schoper tester. moreover.

Tearability test was conducted according to JIS K-8301.
Tear strength (hereinafter referred to as "TRJ") was measured using S8 dumbbells.Chemical resistance was measured using nitric acid containing 22.50% Freon and
% of caustic soda for 24 hours, 1 volume change rate (ΔV)
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]

Density is 0.935g/c as tl hydrogenated polyethylene
m” ethylene copolymer (average molecular weight approximately 25
Chlorinated polyethylene obtained by chlorinating M) with an aqueous suspension (chlorine content M 35.0% by weight,
(hereinafter referred to as rcPEJ) was used.

[(B) Inorganic filler]

As an inorganic filler, Furnace Black (manufactured by Showa Capot Co., Ltd., trade name: Show Black, average particle size: 51 nm)
, specific surface area 41rn'/g, hereinafter referred to as rcB-IJ), Furnace Black (manufactured by Asahi Carbon Co., Ltd., trade name
Asahi Thermal, average particle size 118ns, specific surface area 19m
"/g, hereinafter referred to as rcB-2") and calcium carbonate (average particle size 1.7 microns, hereinafter referred to as rcB-2)
) was used.

[(C) Lead-containing inorganic compound]

As a lead-containing inorganic compound, three Il! Basic lead sulfate (V degree
Approximately 7.0 g/cm", average particle size 2.0 microns.

(hereinafter referred to as "Tribase") was used.

[(D) Lubricant]

As a lubricant, paraffin wax (melting point 63°C, hereinafter referred to as "
``wax'') was used.

[(E) Fluorine-containing organic compound]

As a fluorine-containing organic compound, fluorinated acrylate (r
FAJ) and a barfluoroalkylamine compound (manufactured by Daikin T Gyo Co., Ltd., trade name 22Dyne DS-
201, specific gravity 1.04, hereinafter referred to as rFBJ) was used.

[(F) Organic peroxide and crosslinking aid] Dicumyl peroxide (hereinafter referred to as rD'CPJ) is used as the organic peroxide, and triallyl isocyanurate (hereinafter referred to as rTAIc) is used as the crosslinking aid. ) were used respectively.

[(G) Plasticizer]

Trioctyl trimellitate (r
TOTMJ) was used.

Examples 1-6. Comparative Examples 1 to 4 100 parts by weight of CPE, 30 parts by weight of TOTN,
3.0 parts by weight of wax and 1O tonne negative tribase (in Comparative Examples 1 and 3, no tribase was added) and inorganic fillers whose types and amounts are shown in Table 1, A sheet was formed by kneading the fluorine-containing organic compound, organic peroxide, and crosslinking aid at room temperature (approximately 20° C.) using an open roll for 20 minutes.

Each of the sheets thus obtained was heat pressed for 30 minutes at a temperature of 160°C and a pressure of 200 kg/crn' to create Rubber 5 (width 25 cm, length 15 crn, width 5 cm, thickness 10 mm). . 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 a dumbbell with a thickness of 2ri layers. The results are shown in Table 2.

(Left below) In Comparative Examples 1 and 3, de-1-hydrogenation occurred,
It was not possible to produce a rubber mold.

From the results of the above Examples and Comparative Examples, the rubber mold material obtained by the present invention not only has excellent resistance to strong acids, strong alkalis, and fluorocarbons, but also has good gasoline resistance and It is clear that mechanical properties such as tensile strength and tear strength are also excellent.

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).

(+)1111 Excellent weatherability.

(2) #Good abrasion resistance.

(3) Excellent flexibility.

(4) Good oil resistance (aromatic oil, aromatic oil).

(5) Excellent flexibility and cold resistance.

(6) Good dimensional accuracy.

(7) Not only is molding processability good, but the shrinkage rate during molding is small.

(8) Small compression set.

(9) Good type II property.

(10) Chemical resistance, which is the most characteristic feature of the present invention (especially,
For example, it can withstand nitric acid with a concentration of 50% or more.

The mold material of the chlorinated polyethylene composition obtained according to the present invention exhibits one or more excellent effects, such as automobile parts such as foam backings for dampers, bumpers, headlights, stop lamps, etc., parts of home appliances, etc.
It is promising as a mold material for manufacturing toner rollers, printable rolls, printed circuit boards, parts for electronic devices, and other industrial parts.

Claims (1)

[Claims] (A) chlorinated polyethylene; (B) at least one inorganic filler selected from the group consisting of carbon black, calcium carbonate, synthetic white silicate carbon, calcium carbonate, 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; The composition ratio of the inorganic filler to the chlorinated polyethylene is 20 to 120 parts by weight,
A rubber mold material containing 1.0 to 15.0 parts by weight of a lead-containing inorganic compound, 0.5 to 5.0 parts by weight of a lubricant, and 0.1 to 30 parts by weight of a fluorine-containing organic compound.