Structure design and performance study on homogeneous-reinforced polyvinyl chloride hollow fiber membranes

Homogeneous-reinforced (HR) polyvinyl chloride (PVC) hollow fiber membranes consisting of coating layer and matrix layer were fabricated via coating process. The mixtures of polymer solutions were uniformly coated on the homogeneous PVC matrix membrane which was prepared by melt-spinning method. The influences of PVC concentration and poly(ethylene glycol) (PEG) molecular weight in polymer solutions on structure and performance of HR membranes were investigated. The results showed that the HR PVC membranes had a dense and smooth outer surface compared with matrix membrane. The maximum pure water flux and protein permeation flux of HR PVC membranes were obtained as the PVC concentration reached to 10 wt.% and PEG molecular weight was 2000. The increase of PVC concentration and PEG molecular weight brought about the increase of protein rejection rate and the decrease of membrane porosity. The high flux recovery rate (> 85.00%) indicated that the HR membranes had excellent anti-fouling property. Moreover, the HR PVC membranes had a favorable interfacial bonding force between the coating layer and matrix membrane. The tensile strength of HR membranes decreased slightly compared with matrix membrane and was nearly 19 MPa, but the elongation at break was opposite which was nearly 102%.