PRODUCTION OF ELECTRIC FIELD-APPLIED HOLLOW FIBER

摘要

PURPOSE:A spinning dope is extruded through orifices which have a two-layer structure where the inner nozzle is separated from the outer nozzle with an insulator in an electric field to give a hollow fiber yarn increased hydrophilic properties on their surface and improved flux. CONSTITUTION:The inner nozzle 1 and the outer nozzle 2 are separated from each other with an insulator 3 made of teflon or the like and electrodes 4, 4' provided on both nozzles. The resultant 2-layer orifices are used to effect the extrusion of the spinning dope under application of an electric field of higher than 1V/m intensity whereby the objective hollow fibers are obtained. The spinning dope is not specified, but a polymer having locally dipole moment such as polysulfone or polyether imide is preferred to markedly improve the properties of the resultant hollow fibers.