A series of amphiphilic graft copolymers consisting of poly(vinyl chloride) (PVC) main chains and poly(vinyl pyrrolidone) (PVP) side chains, i.e. PVC-g-PVP, was synthesized via atom transfer radical polymerization (ATRP), as confirmed by 1H NMR, FT-IR spectroscopy, and gel permeation chromatography (GPC). Transmission electron microscope (TEM) and small angle X-ray scattering (SAXS) analysis revealed the microphase-separated structure of PVC-g-PVP and the domain spacing increased from 21.4 to 23.9nm with increasing grafting degree. All the membranes exhibited completely amorphous structure and high Young's modulus and tensile strength, as revealed by wide angle X-ray scattering (WAXS) and universal testing machine (UTM). Permeation experimental results using a CO 2/N 2 (50/50) mixture indicated that as an amount of PVP in a copolymer increased, CO 2 permeability increased without the sacrifice of selectivity. For example, the CO 2 permeability of PVC-g-PVP with 36wt% of PVP at 35°C was about four times higher than that of the pristine PVC membrane. This improvement resulted from the increase of diffusivity due to the disruption of chain packing in PVC by the grafting of PVP, as confirmed by WAXS analysis.
All Science Journal Classification (ASJC) codes
- Polymers and Plastics