CELLULOSIC DERIVATIVE RESIN COMPOSITION, FILM OR SHEET COMPRISING THE SAME

PROBLEM TO BE SOLVED: To obtain the subject composition excellent in impact resistance dimensional accuracy, cutting workability, etc., and useful as a film or a sheet by adding an epoxidized diene-based block copolymer besides a conventionally used plasticizer to a cellulosic derivative resin. SOLUTION: This composition is obtained by compounding (A) 100 pts.wt. of a celulosic derivative resin (e.g. cellulose acetate resin) with (B) 5-70 pts.wt. of a plasticizer and (C) 0.5-50 pts.wt. of an epoxidized diene-based block copolymer. The component C is preferably prepared by epoxidizing a block copolymer of (i) a vinyl-aromatic compound (e.g. styrene) and (ii) a conjugated diene compound (e.g. butadiene) or obtained by partially hydrogenating the above block copolymer and then epoxidizing the partially hydrogenated block copolymer. The copolymerization ratio of the components (i) to (ii) is preferably (5:95) to (70:30) (weight ratio) and the number-average molecular weight of the block copolymer is preferably 5,000-600,000.