Oriented cellulose films and fibers from a mesophase system

Abstract

Abstract Cellulose mesophases were obtained by preparing concentrated solutions of cellulose (20–55%) in a mixture of N ‐methyl‐morpholine N ‐oxide (MMNO) and water. The anisotropy depends on four interconnected parameters: the temperature of the solution which, in general, must be lower than 90°C; the concentration of cellulose which must exceed 20%; a water content such that the mole ratio water/anhydrous MMNO is smaller than unity; and the degree of polymerization of the dissolved cellulose. The anisotropic cellulose solutions can readily be oriented during extrusion or casting thus giving fibers or films which upon regeneration exhibit high orientation.