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Electrospun polyacrylonitrile (PAN) nanofiber membrane was fabricated. The surface of the PAN nanofiber membrane was spray-coated with a hydrophobic paint or knife-casted with an ultra-fine nanofiber cellulose (NC) layer. This was to mitigate the problem of infiltration of the coating solution into the pores of the virgin PAN nanofiber membrane when preparing composite membranes. As a result, defect-free and thin PVA layers were successfully deposited onto the hydrophobic PAN nanofiber or NC-PAN nanofiber substrates by a spray-coating method. The thin film composite (TFC) PVA/NC-PAN membrane exhibited extradentary pervaporation desalination properties. A water flux of 238.7 ± 4.1 kg/m2·h and a salt rejection above 99.8% were obtained using a 3.5 wt% NaCl solution as feed at 80 °C. This is the highest reported water flux of all the PV desalination membranes. Moreover, a high-water flux of 103.1 ± 5.8 kg/m2·h was observed using the composite membrane to desalinate a 20 wt% NaCl solution at 70 °C. The excellent desalination property of the PV composite membrane demonstrates a great potential for recycling brine solutions.

l-Dopa functionalized halloysite nanotubes (HNTs) were prepared by the self-polymerization of l-dopa in the weak alkaline condition. Then different contents of l-dopa coated HNTs (LPDHNTs) were blended into cellulose acetate to prepare enhanced performance ultrafiltration membranes via the phase inversion method. The HNTs and LPDHNTs were characterized by FTIR, XPS, and TEM anysis. And the membranes morphologies, separation performance, antifouling performance, mechanical properties and hydrophilicity were also investigated. It was found that the composite membranes exhibited excellent antifouling performance. The pure water flux of 3.0wt% LPDHNTs/CA membrane increased from 11.4Lm-2h-1 to 92.9Lm-2h-1, while the EA rejection ratio of the membrane was about 91.2%. In addition, the mechanical properties of the resultant membranes were strengthened compared with the CA ultrafiltration membrane.

The binary nanocomposites blended by carboxymethyl cellulose (CMC) and SiO2 nanoparticles were constructed to prepare the films with superior thermal stability and flame retardant properties. The incorporation of cellulose nanofibers(CNFs) and SiO2 nanoparticles were followed to prepare ternary nanocomposite films exhibiting excellent mechanical properties. The mechanism and chemical reaction of the thermal decomposition for the CMC/SiO2 composite membrane were proposed, which showed that the mass residuals were Na2CO3, SiO2 and Na2SiO3, Na2CO3 when the content of the SiO2 nanoparticles was lowered and higher than 9.6 %, respectively. Compared with the pure CMC, micro combustion calorimeter (MCC) showed that the total heat release (THR) and the peak heat release rate (PHRR) both decreased from 6.4 kJ/g to 5.8 kJ/g, 134 w/g to 27 w/g, respectively. Moreover, mechanical properties of CMC/CNFs/SiO2 membrane showed that the toughness and rigidity of the nanocomposites increased by 56.0 % and 63.0 % on the basis of CMC, respectively.