PRODUCTION OF POLYVINYL ALCOHOL YARN

摘要

PURPOSE: To obtain the subject yarn having high strength and excellent water resistance even from a polymer solution of a PVA having a high concentration by subjecting a solution of PVA in an organic solvent having a specific concentration to dry-wet spinning by using a spinning nozzle having capillaries of a specific shape. CONSTITUTION: Firstly, a solution of a PVA in an organic solvent is prepared by using a PVA having 10<5> to 4×10<5> viscosity-average molecular weight V under conditions that weight % concentration C of the polymer solution satisfies the equation. Then the solution is extruded from a spinning nozzle comprising capillaries having a length of >=5 times its diameter into a coagulating bath through an air or inert gas atmosphere once. The obtained undrawn yarn is drawn by a hot drawing method under conditions at 190-250 deg.C in 15-30 draw ratio to give the objective yarn. N-Methylpyrrolidone is preferable as the organic solvent to prepare the spinning stock solution.