Preparation of homogeneous grafting cellulose and partial substitution for polyethersulfone membrane material.

The homogeneous grafting was carried out by using N,N-dimethylacetamide/lithium chloride as the solvent of cellulose. The results showed that the efficient reaction conditions were as follows: reaction time, 2 h; mass ratio of monomer/cellulose, 1/1(g/g); mass ratio of initiator/cellulose, 6/50 (g/g); and reaction temperature, 80 °C. Under these conditions, the grafting percentage could reach 76%. The grafted polymer was characterized by Fourier transform infrared spectroscopy, scanning electron microscope and thermogravimetric analysis. An exploration about the partial substitution of grafted cellulose for polyethersulfone membrane material was carried out by preparing blend membranes. The blend membranes were characterized by tensile testing, pure water flux, scanning electron microscope and differential scanning calorimetry. The results showed that the blend membrane was a compatible system and the blend ratio should be controlled in about 1:16. The introduction of the grafted cellulose may result in the increase of pores size and pure water flux.