PROPYLENE RANDOM COPOLYMER COMPOSITION AND FILM MADE THEREOF

摘要

PROBLEM TO BE SOLVED: To obtain a propylene random copolymer composition which is useful for preparing a film which is excellent in heat sealability and has slipperiness and antiblocking properties necessarey for high-speed bag making by compounding a nucleating agent into a random copolymer of propylene and ethylene and/or 1-butene so as to give a composition having specified caloric properties. SOLUTION: This composition satisfies the conditions: that the peak top temperature Tc ( deg.C) at the highest temperature side in a crystallization curve obtained with a differential scanning calorimeter and the peak top temperature Tm ( deg.C) at the lowest temperature side in a melting curve satisfy the realtion represented by the formula: Tc>=0.75×Tm-5; and that the amount W0 (wt.%) of a component eluted in the temperature range of lower than 0 deg.C in the temperature-rise fractionation chromatograph is 6 wt.% or lower. Preferably, the nucleating agent is compounded in an amount of 0.001-5 wt.% of the random copolymer. Preferably, the random copolymer has a melt index of 0.1-200 g/10 min or has a stereoregularity index P measured by 13C-NMR of 98 mol% or higher.