FIBRES MELT-SPUN FROM A THERMOPLASTIC ALTERNATING COPOLYMER AND A PROCESS FOR PREPARING SUCH FIBRES

摘要

Claimed are fibres melt-spun from a thermoplastic alternating copolymer composed of alkenes and carbon monoxide having a - tenacity BT > 900 mN/tex, - melting point Tm > 220 DEG C, - crystallinity Vc > 33%, and - birefringence DELTA n > 0,0550. The preparation of these fibres, in which process the copolymer is melt-spun and the resulting fibres are subsequently drawn, the spinning process being conducted using a polymer melt free of crystallisation nuclei at a temperature of at most 40K above the melting temperature of the polymer Tm (in K) and the drawing of the fibres being conducted at a temperature in the range of Tmc - 15K to Tmc - 90K, with Tmc representing the constrained melting temperature, at a draw ratio in the range of 5 to 12 and a drawing tension corrected for temperature DTd,corr. in the range of 105 to 300 mN/tex. The fibres were found to be pre-eminently suitable for use as reinforcing yarn in rubber articles such as car tyres.