SU679605A1 - Polyethylene-base conductive composition - Google Patents

Description

The invention relates to electroplating conductive polymer compositions, in particular, to polyolefin compositions used for the manufacture of pipes, sheets, containers, films, and the like. Electroconductive compositions based on polyethylene and acetylene black are known. But such compositions are very fragile and, as a result, cannot be used to make pipes, sheets, films. In order to improve the elasticity of these compositions, elasmers are usually introduced into them (for example, polyisobutylene polybutadiene J2, a copolymer of isobutylene with isoprene 3. However, in this case, the strength of the electrically conductive compositions decreases significantly, which significantly degrades the quality of the products and limits the scope of their application. In addition , the introduction of elastomers increases the cost of the electrically conductive compositions .In order to increase conductivity, strength, elasticity and reduce the cost, the composition based on polyethylene contains alkylating carbon black containing 0.5 to 10 wt.% alkyl groups, in the following ratio of components, wt.%: Polyethylene 70-85 Alkylated carbon black 15-30 For the manufacture of the proposed composition, carbon black, alkylated with compounds containing 2 to 12 carbon atoms is used. Soot is obtained, for example, as follows: 500 g of carbon black, 2 liters of benzene, 140 ml of butyl bromide, and 5 g of boron trifluoride are loaded into the apparatus with LK. The alkylation process is carried out with stirring for 2 hours. After cooling the mixture to room temperature, the carbon black Department from the suspension and dried in a vacuum oven with a residual pressure of 180 mm Hg. Get soot containing 0,510 wt.% Butyl groups. The proposed electroconductive composition based on polyethylene has a specific volume electrical resistance () 2, 5-1 (D-1,310 Ohm-cm and specific surface electrical resistance () 2,1105-1.1-10 Ohm at a temperature and has a yield point at stretching (bu) 106-126 kgf / cm, tensile stress at stretching (fff,) 101 126 kgf / cm and elongation at break () 130-286%.

The proposed composition may contain various target additives, for example, heat stabilizers, anti-corrosion additives, lubricants.

f

The electrically conductive composition can be obtained by mixing the components at a higher temperature, for example, on rollers, in heavy-type mixers, in high-speed mixers, followed by extrusion.

Example I. 85% by weight of low density polyethylene and 15% by weight of blackened carbon black (content

alkyl groups of 0.5 wt.%) BcUOT brush on the rollers for 20 minutes until a homogeneous mass is formed. The resulting composition has a D of 1.1-10 Ohms and 1.310 Ohm "cm at a temperature of 20 ± 3 C-5 and has 106 kgf / cm ffp 101 kgf / cm and 6 286%.

Examples 2-5. The compositions are prepared as in Example 1, but the ratios of the components vary. 0 Data on the composition are given in table 1, the properties are given in table 2.

Examples 6-12 (control) Compositions are prepared as in Example 5-1 MO using schistilated carbon black and polyisobutylene, varying the ratios of the components.

Data on the composition are given in table 1, the properties are given in table 2.

82,517,5

Alkylated carbon black (content of alkyl groups 4.5 wt. ")

3-4

80 20

(also)

75 25

(content of alkyl groups

9weight.%)

70 30

(content of alkyl groups

10 wt.%)

85 15

Acetylene black

7 8 9

80 20 75 25 70 30

60. 20 + 20

0

Acetylene black and polyisobutylene

55 25 + 20

1 45 30 + 25 2

Table