METHOD OF MODIFYING CELLULOSE ACETATES FOR PREPARING FILMS, MEMBRANES AND BIOFILTERS Russian patent published in 2001 - IPC

FIELD: manufacture of films, membranes and biofilters for medical purposes. SUBSTANCE: original cellulose acetate is treated with vapors of mixture of solvents; water and dimechyl sulfoxide or water and dimethyl acetamide at 90: 10-99:1 ratio, respectively, in closed system at room temperature to degree of absorption of vapors of not higher than 5 wt %. Invention makes it possible to prepare films, membranes and biofilters capable of selectively purifying plasma of patient's blood from excessive amount of cholesterol, using simple and ecologically clean method to retain other components, e.g. proteins and electrolytes which are essential for life. EFFECT: more efficient modification method. 6 ex, 5 dwg, 1 tbl