CELLULOSE ACETATE HAVING HIGH MOLDABILITY AND PROCESS FOR PREPARING THE SAME

摘要

A cellulose acetate which, despite the high average degree of polymerization, has a low solution viscosity and a high moldability.The low-molecular-weight fraction of cellulose acetate (such as CTA having an average degree of acetylation of 59.0 to 62.5 %) is eluted with a washing solvent to prepare cellulose acetate having a molecular weight distribution Mw/Mn of 1 to 1.7. The washing solvent may be any solvent capable of swellling or partially dissolving cellulose acetate, for example, a solvent capable of dissolving 0.1 to 30 % by weight of celllulose acetate. Examples of such solvents include ones having a solubility parameter delta of 7 to 12.5 (such as ketones, ethers, organic acids, and esters).