RU2358627C2 - Rubber composition and based on it goods and their method of production - Google Patents

Abstract

FIELD: personal use articles.

SUBSTANCE: invention refers to rubber composition, to forming method of protective items made of this composition, to protective items of complex shape and to protective glove, made of rubber composition by press vulcanisation method. The composition is based on ethylene-propylene-diene caoutchouc mixture skept 40 and butyl rubber bk 1675 taken at equal rate. For fire-resistance qualities the composition contains antimony oxide mixed with chlorinated paraffin 470 and 1100.

EFFECT: produced goods have high mechanical qualities in combination with chemical and fire resistance to it to be used in extreme conditions influenced by aggressive environment, toxic chemical and propellant components.

5 cl, 2 tbl

Description

The invention relates to the rubber industry, in particular to the production of personal protective equipment against aggressive environmental influences, and can be used in the manufacture of shoes, mittens and gloves for work in the oil fields, oil refineries and chemical enterprises, as well as in extreme or emergency situations (getting into zone of fire, water, aggressive environments).

For the manufacture of unformed rubber products, a rubber composition is known containing (parts by weight): ethylene propylene (disk) rubber - 70-90; 3,4-polyisoprene with a content of 3,4-units 69-80% - 10-30; vulcanizing group (thiurams) - 11-17; filler (carbon black) - 50-120; plasticizer (naphthoplast) - 10-34. (RU 2074205, C08L 23/16, 1997.02.27).

However, this composition due to the lack of the necessary elasticity does not allow to manufacture rubber products by molding.

Currently, BL-IM brand latex gloves based on butyl rubber latex are used for protective suits and gloves.

The main disadvantage of latex products is stickiness when exposed to aggressive environments, insufficient tearing rate within 3 kN / m, which leads to rupture of products when working with hard surfaces.

A known composition for the production of a protective coating of mittens for work in the oil field, which contains emulsion polyvinyl chloride, a mixture of dibutyl phthalate and dioctyl phthalate, titanium dioxide (RU 2206253, A41D 19/015, 2001.11.08).

The disadvantage of this composition is the low resistance to the action of oils, oil products, protective coat of mittens.

It is known that for the manufacture of rubber products operated under the influence of atmospheric air, steam and hot water, rubber mixtures based on ethylene-propylene rubber, for example rubber 51-1481, are widely used.

Rubber grades 51-1481 do not have the necessary elastic strength properties, which significantly decrease (up to 40%) during aging in air.

An analogue of the proposed rubber composition is a composition based on polyolefins and triple ethylene propylene diene rubber, which can be used for the manufacture of flexible, weather-resistant various consumer goods. The composition of this composition includes, by weight: rubber SKEPT - 100.0, polypropylene - 25-60, low density polyethylene - 1-10, oil - 20-100, vulcanization accelerators: sulfur - 0.1-2.0 , thiuram -0.1-1.5, altax-0.1-0.5, stearic acid - 0.1-2.0, zinc oxide - 0.5-8.0, or peroxide vulcanization: dicumyl peroxide - 0.1-2.0, bis-maleimide 0.1-2.5, novolac alkylphenol formaldehyde resin 0.2-10.0, organic phosphite 0.02-1.0, pigment 0.01-2 , 0, filler - 0.1-50.0, antioxidant - 0.1-2.0, phthalate plasticizers - 0.5-10.0 (RU 2276167, C08L 23/16, 2006.05.10).

The prototype of the proposed composition is a rubber mixture containing synthetic rubber, zinc white, carbon black, characterized in that it contains ethylene propylene diene rubber (SKEPT) as synthetic rubber, technical carbon type ISAF technical carbon, technical stearic acid (stearin ), organic peroxide, stabilizer-modifier in the following ratio, parts by weight: SKEPT - 100.00; technical stearic acid (stearin) - not less than 1.00; zinc white - at least 5.00; technical active carbon type ISAF - at least 50.00; organic peroxide - 2.5-6.00; stabilizer-modifier - 1-2.5 (RU 2241010, C08L 23/16, 2004.11.27).

This composition does not have the necessary properties for use in emergency situations when exposed to aggressive environments.

The technical result of the present invention is the development of a rubber composition having a complex of mechanical, chemical, fire, electrical insulation properties and is capable of being processed by molding during vulcanization under pressure.

To achieve a technical result, a rubber composition is proposed for the manufacture of rubber products containing synthetic rubber, carbon black, stearin, a stabilizer, characterized in that it contains a mixture of ethylene propylene diene rubber SKEPT 40 and butyl rubber BK 1675, taken in equal proportions; vulcanization accelerator in the form of a mixture of captax and thiuram in a ratio of 1: 2, respectively; a mixture of equal amounts of chloroparaffins 470 and 1100; a mixture of active carbon of the technical grade PM-75 and inactive carbon of the technical grade TG-10, taken in a ratio of 4: 1; sulfur as a curing agent and antioxidant - Neozone D in the following ratio of components, parts by weight:

Synthetic rubber - 100.00 Vulcanization accelerator - 1.95 Stearin - 1.00 Zinc white - 3.00 Antimony trioxide - 10.00 Carbon black - 55.00 Chloroparaffins - 20.00 Vulcanizing agent - 2.00 Antioxidant - 0.50

As a synthetic rubber, the composition contains a mixture of ethylene propylene diene rubber (SKEPT-40) and butyl rubber - BK-1675, taken in equal proportions.

As a vulcanization accelerator, the composition contains a mixture of Captax and Thiuram taken per 100 parts by weight. synthetic rubber in a ratio of 1: 2, respectively.

To give strength products made from the proposed rubber composition, it contains carbon black in the form of a mixture of active carbon of the technical grade PM-75 and inactive carbon of the technical grade TG-10, taken per 100 parts by weight of synthetic rubber in a ratio of 4: 1, respectively.

Chloroparaffins are included in the composition as a mixture of chloroparaffin - 470 and chloroparaffin - 1100, taken per 100 parts by weight of synthetic rubber in equal amounts.

As a vulcanizing agent, the composition contains sulfur, and Neozone D. as an antioxidant.

The presence of antimony trioxide in combination with chloroparaffins gives the products from this rubber composition flame retardant properties.

The rubber composition is prepared on rollers or in a rubber mixer. Calendering of the composition is carried out at a temperature of 80-120 ° C.

Currently known latex technology allows thin-walled seamless protective products of complex configuration to be obtained, however, in terms of resistance to mechanical and chemical influences, they cannot be used when working in extreme emergency situations.

In addition, the limited filling of the latex mixture, a small assortment of latexes, and their instability are a disadvantage of latex technology. The high consumption of solvents makes the process highly toxic and fire hazard.

The present invention provides a method for molding protective articles of complex configuration from a rubber composition of the claimed composition, which is vulcanized on rollers or in a rubber mixer, subjected to calendering at a temperature of 80-120 ° C, and then using a compression tooling consisting of a punch and two half-matrixes, repeating the shape of manufactured products, pressed and vulcanized at a temperature of 170 ° C for 6-10 minutes The casting mold is made of steel. The proposed method in the conditions of the proposed method using semi-matrices of the appropriate profile from the rubber composition of the present invention can also be made shoes, mittens and other products of personal protection from the influence of aggressive environments.

Currently, known protective gloves, which are a textile base coated on one or two sides with a polymer composition, are made by impregnating with a polymer mixture a fabric substrate - a knitted blank from cotton or synthetic yarn and drying. A mold with a cloth backing placed on it is dipped into the polymer mixture.

As a polymer composition, covering the textile base on both sides, a coating based on chloroprene rubber can be used, while the textile basis of the plain weave can be made of fiberglass with a surface filling of 60 70% and a surface density of 90 to 120 g / m ² in a mass ratio bases and polymer coatings (90 120) (230 270), respectively (RU 2070517, B32V 25/10, 1996.12.20).

Such a glove with high heat resistance has a relatively low bond strength of the polymer coating with the glass base, low resistance of the composite material to the action of alternating loads and low resistance of the chloroprene coating to the action of an open flame.

A protective glove, in particular for welding and other work at elevated temperatures, can be made of a warp containing a mixture of polymer filaments and natural fibers, which includes 60.40% heat-resistant polymer filaments or cord on a polyamide basis and 40.60% yarn on the basis of cotton (application 95101059, A41D 13/10, 1996.11.10).

Such gloves with high strength do not have sufficient fire resistance.

Currently used latex gloves based on butyl rubber latex become sticky under the influence of components, for example, rocket fuel, and also break when working with hard surfaces, having a reduced tear index of 3 kN / m.

Known gloves obtained by applying from the inner surface of the glove to the outer surface of a layer of polyurethane, a rubber layer (such as chlorosulfonated polyethylene or ethylene propylene copolymer), a layer formed from a mixture of lead oxide and polychloroprene (to protect against radioactivity) and then again a layer rubber and a polyurethane layer, wherein the rubber layers prevent the polyurethane from reacting with lead oxide. These gloves, although suitable for protection against radioactive radiation, do not have satisfactory mechanical properties (US patent 5165114, A41D 19/00, 1992.11.24).

Also described are gloves containing a layer of rubber (for example, butyl rubber BK), intended for contact with human hands, and a layer of polyurethane, which gives the glove mechanical strength. The rubber layer present on the inner surface of the glove prevents the hydrolysis of polyurethane from coming into contact with the user's hand. Such gloves are used in spacesuits, especially for working with radioactive substances. Their tensile strength is 24 H and their puncture strength is 55 H in accordance with NF EN 388 (patent application FR 2777163).

However, gloves suitable for working with radioactive substances according to the above application do not have a sufficient level of mechanical properties. In particular, their puncture strength and tensile strength do not provide the user with optimal protection.

Using the method of molding by vulcanization in the presses of the rubber composition and protective rubber products of the present invention of a complex configuration, a protective glove is developed for working in extreme conditions with high mechanical properties, combined with chemical resistance and fire resistance, containing synthetic rubber as a basis in the form of a mixture of ethylene propylene diene rubber (SKEPT) and butyl rubber (BK), taken in equal proportions.

Rubber of industrial grade SKEPT-40 was used as ethylene propylene diene rubber, and rubber of industrial grade BK-1675 was used as butyl rubber.

For work in the oil fields, molded products of complex configuration — five-fingered gloves, shoes, and mittens — are produced by vulcanization in presses for the first time. For their manufacture, the workpiece is put on the core, placed in a press of type “Sweet” and subjected to vulcanization for 6-10 minutes at a temperature of 170 ° C.

Molded products from the rubber composition proposed in the present invention withstand 3 cycles of “toxic chemicals (TX) contamination - degassing”, 2 cycles of “rocket fuel component (CMT) contamination - neutralization” (during one-minute contact with MCT) and three times exposure to fuels and lubricants during testing (Fuels and lubricants) (kerosene, gasoline, diesel fuel).

After these effects, the molded products retain their protective properties at the level of the data given in Table 1, have a conditional tensile strength of at least 7.7 MPa and tear resistance of at least 21 kN / m. After exposure to TX, KRT, fuels and lubricants and degassing (neutralizing) solutions, gloves do not stick together and do not change their size and shape.

The products retain protective operational and ergonomic properties after storage in storage conditions for three years and in operating conditions at an air temperature of -40 ° C to + 50 ° C with a relative humidity of 20 to 98%.

Physico-chemical properties of molded rubber protective products made from a rubber composition in accordance with the present invention are shown in table 2.

Table 1 Protective properties of molded rubber products (gloves, shoes, mittens) №№ pp The name of indicators Numerical values of indicators 2 The time of the protective action during dousing with rocket fuel components (CRT) lasting, min: 1 (three times) 3-8 10 (one time) 3-8 3 Protection against burns of hands when exposed, sec: open flame -10-30 heat radiation flux with an intensity of 60-80 kW / m ² 10-25

table 2 Physico-mechanical properties of molded rubber products (gloves, shoes, mittens) №№ pp The name of indicators Numerical values of indicators one Conditional tensile strength, not less than MPa 11.0 2 Tear resistance, not less than kNm 30,0 3 Coefficient of frost resistance at minus 40 ° С, not less 0.2 four Resistivity, no more than Ohm · cm 10 ⁸

Claims (4)

1. A rubber composition for the manufacture of protective rubber products, containing synthetic rubber, carbon black, stearin, a vulcanizing agent, a vulcanization accelerator and a stabilizer, characterized in that it contains a mixture of ethylene propylene diene rubber SKEPT-40 and butyl rubber BK-1675 taken in equal proportions; vulcanization accelerator in the form of a mixture of captax and thiuram in a ratio of 1: 2, respectively; a mixture of equal amounts of chloroparaffins 470 and 1100; a mixture of active carbon of the technical brand TG-10, taken in a ratio of 4: 1; sulfur as a vulcanizing agent and antioxidant - Neozone D in the following ratio of components, parts by weight:
Synthetic rubber 100.00 Vulcanization accelerator 1.95 Stearin 1.00 Zinc white 3.00 Antimony trioxide 10.00 Carbon black 55.00 Chloroparaffins 20.00 Vulcanizing agent 2.00 Antioxidant 0.50 2. The method of molding protective rubber products of complex configuration from the rubber composition according to claim 1, which is vulcanized on rollers or in a rubber mixer, subjected to calendering at a temperature of 80-120 ° C, and then using a molding tooling consisting of a punch and two half-matrixes , repeating the shape of the manufactured products, pressed and vulcanized at a temperature of 170 ° C for 6-10 minutes 3. Protective products of complex configuration, molded according to the method of claim 2 from a rubber composition containing, as synthetic rubber, a mixture of SKEPT-40 ethylene propylene diene rubber and BK-1675 butyl rubber, taken in equal proportions; vulcanization accelerator in the form of a mixture of captax and thiuram in a ratio of 1: 2, respectively; a mixture of equal amounts of chloroparaffins 470 and 1100; a mixture of active carbon of the technical brand TG-10, taken in a ratio of 4: 1; sulfur as a curing agent and antioxidant - Neozone D in the following ratio of components, parts by weight:
Synthetic rubber 100.00 Vulcanization accelerator 1.95 Stearin 1.00 Zinc white 3.00 Antimony trioxide 10.00 Carbon black 55.00 Chloroparaffins 20.00 Vulcanizing agent 2.00 Antioxidant 0.50 4. A protective glove molded by vulcanization in presses of a rubber composition according to claim 1, resistant to toxic chemicals and rocket fuel components, for operation in extreme conditions with high mechanical properties in combination with chemical resistance and fire resistance.