Spreading and drying of starch-glycerol-fiber film produced by tape-casting

The objective of this work was to evaluate spreading and drying processes of starch-glycerol-cellulose fiber film prepared by tape-casting. Suspension spreading was evaluated at 50, 150 and 250 cm min(-1), followed by drying in a forced-air oven at 40 or at 70 degrees C; suspension spreading was also evaluated at 150 cm min-1, followed by film drying on the tape-casting support at 22 degrees C and 60% relative humidity, at air-drying velocity of 4, 6, and 8 m s(-1) in the drying tunnel. Rheological tests showed that suspension spreading at temperatures below 50 degrees C had the modulus of elasticity superior to the modulus of viscosity, in all oscillation frequency spectrum. Micrographs showed films dried at 40 and 70 degrees C without defects and whose mechanical properties showed no differences. Spreading speed and air-drying velocities did not change the drying time and film properties. The drying time can be reduced to approximately two hours, which is important to the scale-up of film production.