Abstract: Carboxymethyl cellulose-chitosan (CMC-CS) blended membranes with different weight ratios(1:2, 1:1, 2:1) were prepared by co-solution method. The structure of membranes was characterized by FT-IR and SEM. The thermal property of membranes was characterized by DSC. The properties of CMC-CS were evaluated by uniformity, acid resistance, tensile strength and absorption rate. The intermolecular mechanism was analyzed. The results indicated that CMC and CS generated polyelec-trolyte through electrostatic and hydrogen-bond interactions. The intermolecule bonds of CMC-CS membranes were degraded between 170℃ and 330℃. At 217.4℃, the ionic bonds were fractured and the electrostatic interaction disappeared. The CMC-CS membrane with a weight ratio of 1:1 was the ideal membrane, whose electrostatic interaction between CS and CMC was the highest. Tensile strength of the CMC-CS membrane reached 34.44MPa, which was 64.47% higher than CS membrane. The maximal acid adaptability was decreased from pH value 5 to 4, and tensile strength of CMC-CS membrane was 25.71MPa after dunking at pH value 6. The water-swelling rate of CMC-CS membranes was effectively reduced.

Key words: carboxymethyl cellulose, chitosan, blended membrane