Thermoplastic elastomer manufacture using a planetary extruder with successive roll arrangements

摘要

A process for manufacturing a thermoplastic elastomer consisting of a mixture of one or more thermoplastic plastics and one or more cross-linked rubbers uses a roll arrangement with an inlet to a conveyer screw feeding roll elements. Each roll element consists of a main spindle and secondary spindles rotating around it and feed points for additives are located at the transition areas of the elements. In a first version of the process 10-90 wt% of thermoplastic plastic material and one or more uncrosslinked rubbers are fed into the inlet of the roll arrangement and melted and dispersed to form a homogenous mixture. The mixture is conveyed axially along the roll arrangement and a cross-linking agent added at a transition area of the rolls is dispersed and homogenised while dynamic crosslinking occurs simultaneously as the thermoplastic elastomer is subjected to high stretching rates producing a rolled out area of 75 sq m/kg of material. In an alternative process the thermoplastic plastics and uncross-linked rubbers are fed together with the cross-linking agent into the inlet orifice of the roll arrangement, melted and dispersed and are simultaneously subjected to the same stretching effect as before during the crosslinking stage.