POLYSTYRENE BASED HEAT SHRINKABLE FILM

摘要

PURPOSE:A film, obtained by blending block SBR with an impact-resistant polystyrene, capable of mounting on glass bottles with good slipperiness at a high speed, having improved slipperiness and blocking properties in a process of passing through hot water for sterilization in a filling line and suitable for coating drink bottles. CONSTITUTION:A polystyrene based heat shrinkable film obtained by drawing a sheet consisting of (A) 100pts.wt. styrene-butadiene block copolymer (block SBR) with70-80wt% styrene content and 30-20 wt% butadiene content and (B) 3-10pts.wt. impact-resistant polystyrene with 4-10wt% rubber content in one direction and having 60-85% shrinkage in the drawing direction and <=15% shrinkage in the direction perpendicular to the drawing direction on heating at 120 deg.C. The above-mentioned film has>=6000kg/cm<2> tensile modulus in the drawing direction and >=5000kg/cm<2> tensile modulus in the direction perpendicular to the drawing direction. The drawing direction is the winding direction of the film.