HIGH-STRENGTH AND HIGH-MODULUS POLYVINYL ALCOHOL FIBER HAVING EXCELLENT HOT-WATER RESISTANCE AND PRODUCTION OF SAID FIBER

摘要

PURPOSE:To obtain the title fiber useful for the reinforcement of rubber such as tire cord, V-belt or hose or as a rope, conveyor belt, fishing net, etc., by spinning a dope of a PVA polymer having high polymerization degree and drawing the obtained fiber under specific condition. CONSTITUTION:The objective fiber having a tensile strength of =15g/d, preferably =20g/d, an elastic modulus of =250g/d, preferably =300g/d, a hot-water resistance of =120 deg.C, preferably =130 deg.C and a steam resistance index of =50, preferably =60 can be produced by spinning a dope of a PVA polymer having a polymerization degree of =1,500, preferably =3,500, drawing the obtained fiber at a draw ratio of =3, preferably 3.5-7, treating the drawn fiber with a crosslinking agent (e.g., hydroperoxide) and subjecting to a dry-heat treatment at a draw ratio of =3.