Morphology and Mechanical Properties of a New Nanocrystalline Cellulose/Polysulfone Composite Membrane

ABSTRACT A new nanocrystalline cellulose/polysulfone composite membrane was prepared. The composite membranes were coagulated in different coagulation baths (i.e., water, methanol, ethanol, isopropanol) and concentrations (i.e., 10, 30, 50 v/v %). The chemical structure of membrane is characterized by Fourier transform infrared spectroscopy. The viscosity of the casting solutions was measured. The cross‐section morphology of the membrane was characterized using scanning electron microscopy. The mechanical properties were also studied. Results showed that the connectivity of nanocrystalline/polysulfone composite membrane pores is better than that of pure polysulfone membrane, macrovoids, and short finger‐like pores are produced when adding methanol, ethanol, or isopropanol into the coagulation bath. As the coagulant concentration increases, the sponge‐like structure becomes looser and thinner. A right amount of nanocrystalline cellulose has a positive effect on the tensile strength. The tensile strength of the pure membrane in different coagulation baths shows the following order: methanol > ethanol > isopropanol > water (10 % v/v).