Patent ID: 11920018
Assignee: BOREALIS AG
Field: Other special machines (Mechanical engineering)
Classification: CPC C  B  H | IPC B  C  H

Claim 0:
1. A process for preparing a semiconductive polymer composition, comprising the steps of:
i) introducing 30-90 wt % of a polymer component (a) and 0-8 wt % additives in a mixer device and mixing the polymer component and additives at elevated temperature such that a polymer melt is obtained;
ii) adding 30-70 wt % of a carbon black (b) having a mass pellet strength (MPS) according to ASTM D1937-13 of from 50 to 180 N and further mixing of the polymer melt to obtain a semiconductive polymer mixture, wherein the carbon black (b) has an average pellet size according to ASTM D1511-12 of from 0.1 to 5 mm, an average value of individual pellet hardness for the 5 hardest pellets (M5H) according to ASTM D5230-13 of from 15 to 35 cN, an average value of individual pellet hardness (CSAV) according to ASTM D5230-13 of from 10 to 30 cN and an iodine adsorption number measured according to ASTM D1510-13, method A of from 38 to 48 g/kg; and
iii) extruding and pelletising the obtained polymer mixture.