SU1002313A1 - Vulcanizable polymeric composition based on stereoregular rubber - Google Patents

Description

This invention relates to the rubber industry and relates to the development of a vulcanizable polymeric composition based on stereoregular rubber.

A vulcanizable polymeric composition based on stereoregular rubber, such as CIS-polyisoprene, is known, including rubber fillers: carbon black (acetylene) and graphite, for example in a ratio of 100: 70: 35 1.

However, the required volume resistance of the vulcanizates of such a composition (not more than 10 ohm cm) for the cable screen is achieved only at very high soot content - more than 2 weight. h. on 1 weight. h. graphite and more than 100 weight. hours per 100 weight. rubber rubber; however, the composition has low plasticity, and vulcanizates have low strength 1.

Also known is a vulcanizable polymer composition based on stereoregular rubber, including fillers — graphite and highly structured carbon black treated with a 0.2–0.6% solution of nitric acid in a ratio (wt.%): 30–35: 16.5– 25: 20-40 2,

However, this mixture has lower ductility, electrical conductivity, and rubber from it - low strength.

The purpose of the invention is to simultaneously increase the plasticity of the composition, electrical conductivity and strength of the rubber from this composition.

The goal is achieved by

Q that a vulcanizable polymeric composition based on stereoregular rubber, which includes soot and graphite as fillers, contains active furnace soot with a porosity factor of 2.4–3 and a ratio of macropores and micropores of 1: 2–4 and graphite with a ratio of carbon black 0.75-6.0: 1 in the amount of 95170 weight. h of fillers per 100 weight parts of rubber.

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The invention is illustrated by examples. Example 1. On laboratory rolls with a roll temperature of 7080 0 and rubber loading 200 g, a vulcanizable polymer composition of the following composition is prepared (by weight): cis-polyisoprene SKI-3-50, cis-polybutadiene SKD-50, stearic acid . that - 10, zinc oxide - 5, dibutyl phthalate - 10, transformer lo - 30, neozon D-1, captax - 1.5 thiuram 2.5 and a mixture of active furnace black and graphite in a ratio of 1.22133 (carbon content 73 weight. hours and graphite 60 parts by weight per 100 weight parts of rubber). The active furnace soot had an elementary particle diameter of 23 m and a specific geometric surface 102,. a specific external surface of 148 and a specific absorption surface of 253 m / g. The soot surface porosity coefficient is 2.48; the ratio of the surface area of macropores and micropores - 1; 2.3 The preparation of the composition is repeated, increasing the content of graphite to 73 parts by weight. per 100 weight parts Rubber. Accordingly, the ratio of carbon black and graphite is reduced to 1, and the content of the carbon black mixture with c-graphite increases to 146 weight. h. per 100 weight, h. rubbers. The preparation of the composition is repeated, increasing the content of graphite to 80 wt. hours and transformer oil to 40 weight.h. per 100 weight parts rubbers. Accordingly, the ratios of carbon black and graphite are reduced to 0.91, and the content of the mixture of carbon black with graphite is increased to 153 weight. hours per 100 weight. H. rubbers. The preparation of the composition is repeated, increasing in it the content of graphite to 9 wt. h. and transformer oil to 50 weight. h, per 100 weight.h rubbers. Accordingly, the ratio of carbon black and graphite is reduced to 0.71, and the content of the mixture of carbon black with graphite is increased to 163 weight. hours per 100 weight. H. rubbers. The preparation of the composition is repeated, changing the content of carbon black in it to 83 wt. h. grafit to 14 weight. h per 100 weight. H. rubbers. Correspondingly, the ratio of carbon black to graphite is increased to 6, and the content of the carbon black to graphite mixture is reduced to 97 weight.h per 100 weight. h, rubbers. The preparation of the composition is repeated, changing the content of soot in it to 73 parts by weight, graphite to 9 parts by weight, and transformer oil to 40 parts by weight per 100 parts by weight. rubbers. Accordingly, the ratio of carbon black and graphite is reduced to 0.77, and the content of the mixture of carbon black with graphite is increased to 168 parts by weight. per 100 weight parts rubbers In parallel, a control composition of the same composition was also prepared with a mixture of highly structural furnace soot PM-1003 according to TU 3811532-7 treated with granulation with a 2% aqueous solution of nitric acid, with graphite in a ratio of 1 with a total mixture content of 146 wt. parts per 100 weight, parts of rubber. Ready also two control compositions of the same composition, containing respectively 146 parts by weight. and 160 weight.h. Acetylene black mixtures according to Specifications 14-7-24-73 with graphite at a ratio of 1 and 2.2. The plasticity of vulcanizable polymer compositions is determined according to GOST 41553. The vulcanization of the compositions was carried out in a press for 15 minutes. The results of testing the compositions and their vulcanizates are given in Table. 1. Example 2, On laboratory rolls with a roll temperature of 8090 C and loading of rubber 300 g, a vulcanizable polymer composition of the following composition is prepared (parts by weight): cis-polyisoprene - 100, stearic acid 10, zinc oxide - 5, neozone D-2, captax-1, 2, dibutyl phthalate - 10, pine resin - 10, sulfur - 1.5, and a mixture of active furnace soot of example 1 with graphite in a ratio of 0.75-140. The results of testing the composition are given in table. 2. Frost. The vulcanizable polymer composition was prepared in accordance with Example 2, but a mixture of active furnace black was used in Example 1 with graphite in a ratio of .1.6 in an amount of 130 parts by weight. per 100 weight parts rubber. The results of testing the compositions are given in table. 2. EXAMPLE 4. A vulcanizable polymer composition was prepared according to Example 2, but a mixture of active furnace black was used in Example 1 with graphite in a ratio of 1.33 in an amount of 140 parts by weight. per 100 weight.h, rubber. A composition is also prepared in which a mixture of carbon black and graphite is contained in a 1: 1 ratio in an amount of 160 parts by weight. per 100 weight parts rubber The results of testing the compositions are given in table. 2. Example 5. A vulcanizable polymer composition was prepared in accordance with Example 2, but an active furnace soot with a particle diameter is used in the mixture of fillers. 29 MMK, specific geometric surface 82, specific external surface 118, specific adsorption surface 219. The soot surface porosity coefficient was 2.7, and the surface area ratio of macropores and micropores was 1: 4. The results of the test composition are given in table. 2. From the table. 1, it can be seen that the proposed vulcanizable polymer composition with an equal ratio of carbon black and graphite and the content of their mixture exceeds the known composition with acetylene black carbon in electrical conductivity and rubber strength. Increasing the degree of filling of the control composition with acetylene aj to higher ratios with graphite leads to a decrease in

electrical resistivity of rubber, i.e. to increase their conductivity, but the strength of such

The composition and properties of polymer compositions and their vulcanizates based on a combination of rubbers SKI-3 and SKD (1: 1) in example 1

rubber and plasticity of the composition, in contrast to the proposed composition, are below the established norms.

Table 1

Properties of vulcanizable polymeric Table2 compositions based on cis-polyisoprene

When the content of the mixture of furnace soot and graphite in the range of 95-170 weight.h. per 100 weight parts rubber and the ratio of soot and graphite from 0.75 to 6 composition satisfies the requirements of consumers to the quality of the screens of cable products. This makes it possible to use the proposed composition for the manufacture of an elastic screen instead of a metal one, which will make it possible, by saving metal, to obtain a large economic effect and also increase the reliability and durability of the cables, since the elastic screen is more resistant to mechanical effects than a metal braid. and does not corrode when using the cable.

So, as can be seen from the presented examples, the proposed composition in comparison with the prototype is characterized by increased ductility, and the rubber of this compromise has improved electrical conductivity and strength.

Continued table. 2

Claims (2)

1. Kabanov, Yu.F., and others. On the thermal conductivity of electrically conducting polymeric materials. Kozhevenno-Obuvna Pro, 5, 1977, p. 52. mind 2. USSR author's certificate No. 674427, cl. C 08 L 9/00, 1975.