同质编织管增强型聚丙烯腈中空纤维膜研究

利用二维编织技术将聚丙烯腈(PAN)纤维编织成中空编织管,以聚丙烯腈为成膜聚合物,以聚乙二醇为成孔剂,配制铸膜液,采用同心圆纺丝法制备同质编织管增强型聚丙烯腈中空纤维膜.研究结果表明,所得同质编织管增强型聚丙烯腈中空纤维膜的表面分离层具有类似于非对称膜的结构,铸膜液可渗入编织管纤维束中;随着编织管编织节距的增大,同质编织管增强型聚丙烯腈中空纤维膜表面分离层厚度减小,同时膜的平均孔径增大,膜的纯水通量随之增大;铸膜液渗入编织管纤维束的现象未影响膜的通透性能;编织管的断裂强度最大可达100 MPa以上.通过水浴振荡、超声波水浴振荡及等力拉伸3种方法测试了同质编织管增强型中空纤维膜和异质编织管增强型中空纤维膜中编织管与表面分离层之间的界面结合性能,结果表明前者的界面结合性能优于后者.

STUDY ON HOMOGENEOUS BRAIDED TUBE REINFORCED POLYACRYLONITRILE HOLLOW FIBER MEMBRANES

Homogeneous braided tube reinforced polyacrylonitrile(PAN) hollow fiber membranes which contained hollow braided tube and separation surface were prepared by concentric circles spinning method.The braided tube was prepared by the two-dimensional braided technique using PAN fibers.While the separation surface was obtained by non-solvent induced phase separation method with PAN as the polymer matrix,dimethyl sulfoxide(DMSO) as the solvent,and polyethylene glycol(PEG) as the pore-forming agent.Results showed that the structure of separation surface was similar to asymmetric membrane.The casting solution would penetrate into the voids among fiber bundles of the braided tube.As the braided pitch increasing,the thickness of separation surface decreased,which induced the promotion of the membrane water flux.There was no obvious influence of casting solution penetration on the membrane permeability.The breaking strength of braided tube was up to 100 MPa.Water bath vibration,ultrasonic vibration and the same axial tension force were utilized to investigate the interfacial adhesion between separation surface and braided tube of homogeneous and heterogeneous braided tube reinforced hollow fiber membranes.The results showed that the interfacial adhesion of the homogeneous one was superior to that of the heterogeneous one.