| The carbon black particles are strongly attached to a cross-linked polyethylene network, and they can not be separated from the network even by refluxing in a boiling xylene for many hours at the temperature higher than the melting point of cross-linked polyethylene. It is thus expected to reduce the free movement of the carbon black particles at high temperatures, and to greatly improve mechanical, thermal and electrical stability. The degree of the cross-link is determined in a gel reflux extraction, and the relation among the cross-link effect, additives and gel fraction is discussed.(5 refs.) |
