VERFAHREN ZUR HERSTELLUNG VON TEILEN AUS THERMOTROPEN FLUESSIGKRISTALLINEN KUNSTSTOFFEN MIT DEFINIERTER ORIENTIERUNG DER LC-POLYMER-MOLEKUELE SOWIE DIE SO HERGESTELLTEN TEILE.

摘要

A process is claimed for the prodn. of parts from thermotropic liq.-crystalline plastics (I) with specific mol. orientation in at least two independent pref. directions, by extrusion through a nozzle, during which process the material flowing through the nozzle under pressure is at least temporarily subjected to elongation in two or more given directions, to stretch the chain mol., by means of the forces applied over the form of the boundary surfaces. Parts such as films, sheets, and sections, are also claimed., mfd. by this process. Pref. (I) are polyesters contg. the units -O-R-CO-, -O-R'-O-, or -CO-R''-CO-, with R', R'' = C6H4, 2, (5, 6, 7, or 8)-naphthylene, or C6H4-X-p-C6H4, in which X = S, O, CO, CMe2, SO2, NR, NH, or direct bond. One- or more-phase mixts. of (I) and other polymers can be used, and processing is carried out from the thermotropic or the isotropic melt phase. The process is applicable esp. to fully aromatic polyesters and is carried out pref. at 200-400 deg.C.