| 摘要 |
PURPOSE:To provide a film composition containing synthetic silica having specific physical properties in a specified amount, excellent in transparency, luster, mechanical strength, and especially lubricity at a high temperature, and useful for automatic heating and charging package of foods, etc. CONSTITUTION:The objective composition is by dry-blending (A) 100 pts.wt. of crystalline PP with (B) 0.1-0.3 pt.wt. of synthetic silica (average particle diameter: 2.5-5mu; apparent specific gravity: >=0.1g/ml; pore volume: <=1ml/g), melt-kneading the blend at 190-300 deg.C and subsequently pelletizing the product. The component A is preferably the copolymer of propylene and ethylene or >=4C alpha-olefin [its content is 1.5-4.0wt.%] giving an extract of <=20% by a cross fractionation using ortho dichlorobenzene as a solvent at 80 deg.C and having a MFR of 1-10g/10min. |
