PROCESS FOR THE MANUFACTURE OF THERMOPLASTIC MATERIAL, THERMOPLASTIC MATERIAL OBTAINED AND ITS USE AS A HIGH TEMPERATURE RESISTANT TRANSPARENT MATERIAL

摘要

PROCESS FOR THE MANUFACTURE OF THERMOPLASTIC MATERIAL, TERMOPLASTIC MATERIAL OBTAINED AND ITS USE AS A HIGH TEMPERATURE RESISTANT TRANSPARENT MATERIAL The invention relates to a process for the manufacture of thermoplastic material which has a high glass transition temperature, this process being characterised in that a starting polymer is prepared, containing anhydride units among its constituent units, in that a sufficient quantity of primary amine or of a mixture of primary amines is reacted for the anhydride units to be converted at least partially to acid-amide units, and in that the ring closure of the polyacid-amide obtained is carried out. The thermoplastic material obtained can be used especially to form high temperature resistant optical fibres. (no drawing)