| 摘要 |
A mixture of substances is fed to an extruder and, after being homogenized and liquefied, is extruded on an electric conductor or as a pipe. To meet electric cable specifications, the insulating material used is a polyolefin, such as polyethylene, cross-linking of which is brought about by the addition of a silane, a free-radical generator, and a silanol condensation catalyst. After extrusion, cross-linking takes place in the presence of moisture. To facilitate penetration of the moisture and accelerate cross-linking, an agent capable of reducing the rate of crystallization of the polymer, such as vinyl acetate, is used as a further additive. |
