CELLULOSE-BASED FIBERS FROM LIQUID-CRYSTALLINE SOLUTIONS .2. PROCESSING AND MORPHOLOGY OF ACETATE BUTYRATE ESTERS

Fibers were spun from isotropic and anisotropic dimethylacetamide solu tions of cellulose esters. Take-up speeds of the dry jet/wet spinning process varied. Water served as the coagulant. The mechanical properti es of the fibers increased as spinning progressed from the isotropic t o the anisotropic state of the solution. A trade-off in solubility and fiber properties was noted as the butyryl acetyl ratio decreased. Whe reas high butyryl content enhances both overall solubility and the for mation of liquid-crystalline solutions at lower concentration, it resu lts in lower fiber modulus and strength. Morphology of the fibers depe nded on the coagulation rate which was influenced by the concentration of the spinning solution. The level of orientation and crystallinity of the fibers increased somewhat when they were spun from liquid-cryst alline solutions. (C) 1993 John Wiley & Sons, Inc.