Extruder for silane-polyolefin mixts. - has short screw and low shear mixing zones

摘要

An extruder used for single step mixing, plasticising, grafting and moulding of silane/polyolefin compsns. esp. those with a filler content of greater than 10% have a screw length 20-28 times its diameter (D) and a mixing zone with operates at low shear. Premature crosslinking is avoided since residence time in the extruder is is reduced and mixing is carried under reduced shear. The compsn. is esp. used for cable insulation. The extruded insulation has a smooth, spot-free surface.