Preparation and properties of polytetrafluoroethylene/CaCO_3 hybrid hollow fiber membranes

摘要

A novel method of preparing polytetrafluoroethylene (PTFE) hollow fiber membrane was presented by utilizing poly (vinyl alcohol) (PVA) can form a gel of two dimensional complex compounds with Boric acid (H_3BO _3). Effects of H_3BO_3 on PTFE nascent hollow fiber were investigated, and the results showed that the introduction of H _3BO_3 effectively reduced the addition of PVA. The configuration named "fibril" formed between PVA and H _3BO_3 could be observed in nascent hollow fiber by SEM (Scanning electronic microscopy). Furthermore, Calcium carbonate (CaCO _3) particles (60 nm～ 90 nm) were introduced into PTFE matrix. The interfacial microvoids (IFMs) which were different from the PTFE sintering or node-fibril network structure were obtained. The assumption of the IFMs formation was proposed in this study. Effects of CaCO_3 amount and draw ratios on structure and properties of hybrid hollow fiber membranes were analyzed, and the SEM results showed that the IFMs quantity and diameter improved with draw ratio increasing.