| 摘要 |
PURPOSE:While it is filled with a specific liquid in the hollow part, a hollow fiber is hydrolyzed to keep its esterification degree in a certain range, thus producing a cellulose ester hollow fiber membrane with good deaeration from the inner and outer surfaces of the membrane and high flux. CONSTITUTION:A spinning dope of cellulose ester is extruded through the outer annular slit of a spinning orifice with a double-layered structure and simultaneously a liquid incompatible with alkali aqueous solution such as benzene, toluene, light oil, kerosine, fluid paraffin or perchloroethylene is injected into the inner tube of the orifice. The extruded yarn is led through a gas atmosphere into an aqueous coagulation bath to effect coagulation. Then, the resultant yarn is washed wit water, introduced into an aqueous alkali to effect hydrolysis so that the average esterification degree of the resultant yarn X is in such a range as satisfying the equation (y is the average esterification degree before hydrolysis). Then, the alkali remaining on the fiber surface is neutralized with aqueous acetic acid and washed with water thoroughly. |
