Abstract
Cellulose acetate films are stretched uniaxially by swell-wet process in acetone aqueous solution at room temperature, because the stretching of this film by hot dry process in very difficult. The swelling agent consists of a mixture of a good solvent (acetone) and a poor one (water). The optimum mixing ratio for the swell-wet process stretching was determined. The stretchability of film by swell-wet process was evaluated by stretching work which depends on stretching conditions such as concentration of swelling agent, stretching temperature and rate of stretching, etc.. The results of stretchability of cellulose acetate film by swell-wet process are summarized as follows. (1) The films are had swelling of isotropy under the influence of film-forming by flow-casting method. (2) In view of kinetic analysis the stretching working can be better measure for the evaluation of stretchability of film by swell-wet process. (3) The most suitable swelling agent for stretching of the film by swell-wet process should be 40/60∼50/50 in the ratio of acetone/water at room temperature based on the evaluation of maximum stretching work.
