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Nano-TiO2/poly(methylmethacrylate) nanofibres were prepared by electrospinning with poly(methylmethacrylate) (PMMA) and anatase nano-TiO2 as main materials which were blended mechanically and dissolved in dimethylformamide (DMF) and ethyl ethanoate (EA) solvent. The nanofibres morphologies and physical states were investigated using scanning electron microscopy (SEM), X-ray diffraction (XRD), thermogravimetry analysis (TG), fourier transform infrared (FTIR) spectroscopy and UV–visible (UV–Vis) spectroscopy. Scanning electron microscopy observations revealed that when the content of TiO2 was 5%, nano-TiO2/poly(methylmethacrylate) nanofibres had the minimum average diameter which was 409 nm. Results from FTIR, XRD and TG suggested that anatase nano-TiO2 had been successfully introduced to the PMMA matrix and TiO2/PMMA nanofibres had good thermal stability within 300 °C. Results from UV–Vis suggested that when 10% of anatase nano-TiO2 was added, the photocatalytic decomposition of methyl orange was 50% higher than that of pure PMMA nanofibres under sunlight irradiation for 5 h. [ABSTRACT FROM AUTHOR]

1-acryloylpyrrolidine-2-carboxylic acid (APCA) monomer was copolymerized with acrylonitrile (AN) by aqueous suspension polymerization. High molecular weight (HMW) copolymers of AN and APCA [poly(AN-co-APCA)] with different copolymer composition were successfully prepared by employing azobisisobutyronitrile (AIBN) as initiator and polyvinyl alcohol (PVA) as dispersant in a H2O/N,N-dimethylformamide (DMF) mixture at 60°C. The PAN homopolymer and copolymers were characterized by elemental analysis (EA), nuclear magnetic resonance (NMR), Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), and X-ray diffraction (XRD). The EA results indicated that the content of oxygen increased significantly in PAN copolymers with increasing APCA content. The APCA copolymer composition calculated from the EA was higher than that from1H NMR spectra. The FTIR spectra of PAN and poly(AN-co-APCA) with different monomer ratios confirmed that the contents of APCA units in the copolymer chains increased with increasing APCA content in the feed. The DSC exotherms revealed that copolymerization with APCA could slow the rate of the exothermic reactions during the heat-treatment processes. The XRD results indicated that the PAN homopolymer and copolymers poorly crystallized and the crystallinity decreased with increasing APCA contents. [ABSTRACT FROM PUBLISHER]