SU372823A1 - - Google Patents

Description

composition ON

one

Known coma, positions based on diorgiopolisiloxane rubber, diorganoborsiloxane rubber, filler, organic peroxide.

According to the invention, in order to obtain an auto-adhesion composition that is tight: to adhere to the cream-inorganic elastomers, M, M-dinitroso-N, N-dimethylterephthalamide is added to the composition and per 100 wt. Diorganopolysiloxane rubber components are taken in the following ratio (in weight. h.):

Diyur.Ganoborsiloxane

rubber4 -12

Filler20 -90

Organic Peroxide1 - 6

N, N-dinitropo-N, N-di: methyl terephthalamide, 5-10

This composition, when heated, is capable of vulcanizing into elastomers, which have the ability to self-stick almost instantly, as well as to glue with organosilicon elastomers.

Diorganopolysiloxane rubber used according to the invention has the general formula

GK

Ro4siofR

B

where R is the same or different monovalent hydrocarbon radicals | kalah or substituted hydrocarbon radicals;

R is the same or different radicals: hydrogen, Si (R) 3, n from 1000 to 20000,

moreover, the minimum is 60% of the total amount of R consists of methyl radicals and 0.03-2% of vinyl radicals.

DiorganObrasilOXane rubber (get

when heated oxygen derivative

boron with a liquid organ. polysiloxane with a viscosity of 3–1000 centipoise at 25 ° С, containing

1.9-2 organic chips per atom of silicon.

As filler can be used

silica with a high specific surface area

gas soot | y. Silica Surface .can

be treated with octamethylcyclotetrasiloxane. Filler particles have a meter

a few microns to several

dextral mkron. BASED ON DIORGANOPOLYSILOXANE RUBBER

Vulcanization of the composition is carried out under the action of organic peroxide or omeoi of organic lerekis, for example, cumyl peroxide, benzoyl peroxide, perbenzoatg / 7g-butyl, 2,4-dichloro | benzoyl peroxide, etc.

In order to avoid aging of the composition during storage, it is advisable to add one or more organosilicon compounds, for example tetramethylenedioxydimethylsilane, difbnilsilandiol, etc.

In order to obtain the above composition, the components are thoroughly mixed with the usual apparatus used in the rubber industry. First, a homogeneous filling agent, a plasticizer, and other additives (pigments, antioxidants, a stabilizer) are dispersed in the diorganol polysilac1ananoBom rubber. Diorganoborsiloxano is then added (rubber is heated, the mixture is heated to 80-100 ° C, after which the temperature is reduced to room temperature and organic peroxide is introduced, either directly or by use.

The catalyzed composition can be transformed by extrusion and calendering into sheets, tapes, strips and shaped articles. Curing is carried out by heating in air (ISO-280 ° C).

The resulting elastomers can be used to isolate electrical wires, to coat pipes and pipelines. The composition can also be used for fixing various kinds of elements, for example metallic, on siloxone elastomers, as well as for interconnecting silicone elastomers.

Example. Homogenous composition A-1 receive, mixing (grinding), in a two-cylinder mixer (in g):

Dimethylpolysiloxane rubber with terminal hydroxyl groups (contains 0.2% by weight of methyl1-vinylsiloxy groups, viscosity at 25 ° С

18X106 spz) 100

Heat-treated silica with high specific surface treated with octamethylcyclotetrasiloxane - 36

Methylpolyborsiloxane rubber6, 8

a, (o-di10 (KSidimetil1polisilak Sanovo oil (contains

13 wt. % hydroxyl groups, viscosity 40 centipoise at 25 ° C) 1.35

A mixture of S, S-dinitroso-K1, S-dimethyl terephthalamide and a, to bis- (trimethylsiloxy) -dI1methylpolysiloxane ma | S viscous 100,000 centipoise at 25 ° C, taken in a ratio of 50: 5011

g / 7g-Butyl ester of perbenzoic acid1,17

A mixture of benzoyl peroxide and a, schbis - (trimethylsiloxy) - dimethylpolysilomsan oil with a viscosity of 1000 spz at 25 ° C, taken in a ratio of 50: 50-1,17

The composition is extruded in the form of a PA1 tape, which is then vulcanized for 75 seconds in a K-meter at a temperature of 180-220 ° C. The resulting tape is a microporous material 28 mm wide and 0.5 mm thick. When she wraps the copper bus, she immediately glues the layers, forming a uniform coating, insulating and porous.

When performing the same wrapping with the PB1 tape, obtained similarly to the previous layers from composition B-1, but not containing N, N-dinitroso-M, N — dimethyltetraphthalamide, it takes at least 22 hours to obtain a uniform coating.

Ready three elastomers of known type by air curing of the following compositions.

Composition A.

The following components are mixed (in g): a, w-Dioxymethylpolysiloxane oil with a viscosity of 5000 sps at 25 ° С, containing 0.2 wt. % dietrox groups 100

Iron Oxide65

Diatomitov-land 25

Polyethyl silicate containing

40 wt. % silica 3

The product of the reaction of dibutyl tin dilaurate with orthotitanoic acid butyl ester, mixed in weight. 100: 27 when heated for 3 hours at 120 ° C. 1 After 24 hours of holding the composition at room temperature, it turns into an elastomer.

Composition B.

The following components are mixed (in g): a, co-dioxindi, methylpolysnloxane oil with a viscosity of 5000 sps at 25 ° C, containing 0.2 wt. % hydroxyl group100

Fine carbonate

calcium 40

Polyethylamine containing

40 wt. % silica 3

The product of the interaction of dibutyl tin dilaurate with orthotitanoic acid butyl ester, taken in a weight ratio of 100: 27, with heating for 1 hour at 120 ° C

After 24 hours at room temperature, the composition cures to an elastomer.

Composition B.

The following components are mixed (in g): a, d) -dioxymethylpolysiloxane oil, viscosity 20,000 cm3 At 20 ° C, containing 0.2 volts. % hydrosilane groups100

Silica (diatomite) 25

Silica obtained by heat treatment with a large specific surface 5 Methyl-tri-cethoxysilane 4 The composition is converted to an elastomer after 48 hours at oriental temperature.

Tapes PA1 and PB1 are placed on the surface of each elastomer and allowed to stick together for 30 seconds under a pressure of 5 bar. The force required to unstick the tape is then determined using a dynamometer. The results are shown in the table.

Subject invention

A composition based on diorganapolysiloxane rubber, dioorganoborsiloxam rubber, filler, organic peroxide, characterized in that, in order to obtain an autoadhesive composition capable of tightly fitting to the organosilicon measures, the composition was put into the composition of the adhesion composition, which is tightly applied to the silicon, to the composition, the composition was put into the composition of the adhesi - dimethylterephthalamide and 100 weight. h diorganopolisiloksonovogo rubber 15 Ka something (in the weight h.):

Diorganaborsil ocean marketing

rubber4 -12

Filler20 -90

Organic Peroxide1 - b

20M, K-Dinitroso-.M, Y-dimethylterephthalamide 0, 5-10