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The interaction between polyacrylonitrile (PAN) and various plasticizer at different temperature was discussed by infrared analysis. At the room temperature, the interaction between nitrile groups of polymer is so strong that the conventional plasticizer propylene carbonate (PC) or new-type plasticizer ionic liquid can’t have interaction with nitrile groups. However, the interaction between nitrile groups weakens at higher temperature, i.e. 160°C, and the interaction between the nitrile groups and IL is formed, which is maintained when natural cooling to 90°C. The interaction between the nitrile groups and IL weakens again when natural cooling to room temperature, it may be attributed to the interaction between IL and water is stronger than that of IL and PAN.

Poly (vinylidene fluoride) (PVDF) hybrid membranes reinforced by hydrophilic nanoSiO2 particles were fabricated from PVDF/N-dimethylacetamide (DMAc)/γ-butyrolactone (γ-BL) system via thermally induced phase separation (TIPS) process. Surface and cross-sectional morphology of membranes were characterized by scanning electron microscope (SEM). The properties such as permeability, mechanical performances and antifouling property were also determined. The results showed that the pore size of membrane surface became smaller, while cross-sectional morphology was changed from bicontinuous structure to cell structure, the pore size became larger and majorities of closed pores became open with the addition of hydrophilic nanoSiO2 particles in the system. Compared with pure membrane, pure water flux of hybrid membrane increased by 30.3%, i.e. from 290 to 378 L/(m2·h·0.1MPa), antifouling property increased from 63.1% to 80.2%. Meanwhile, tensile strength and elongation at break increased by 70.6% and124%, respectively.

Poly (vinylidene fluoride) (PVDF) hollow fiber membranes were successfully prepared using DMAc/γ-BL as the mixed diluent and PEG as the additive through modified thermally induced phase separation (M-TIPS) process. The membranes prepared were characterized by scanning electron microscope. Their properties such as water permeability and mechanical properties were also determined. The results show that PVDF membranes have spherical crystallites structure with interconnected network structure because of the combination of solidliquid and liquid-liquid phase separation. When using 25wt% aqueous ethanol solution as the coagulation, the PVDF hollow fiber membrane shows the tensile strength, i.e.4.59MPa and pure water flux, i.e.415 L/ (m2·h).

A new membrane carrier was presented to immobilize zero-valent iron nanoparticles (ZVI NPs) for the removal of contaminants in water. The modified PAN-based oxidized membrane was prepared through acid treating method and used as a nanoreactor to chelate Fe (III) ions for the reductive formation of highly reactive ZVI NPs. The ZVI NP immobilized membrane system is stable and effectively degrades trichloroethylene (TCE). These results suggest that PAN-based oxidized membrane containing ZVI NPs exhibits the good properties and significant potential for environmental applications.