MULTILAYER THERMOPLASTIC FILM WITH IMPROVED PUNCTURE RESISTANCE PERFORMANCE

摘要

The present disclosure provides for a heat-shrinkable, biaxially stretched, multilayer thermoplastic film that includes at least a puncture resistant layer. The puncture resistant layer is formed with a polyethylene based plastomer having a density of 0.890 g/cm³ to 0.910 g/cm³ as measured in accordance with ASTM D-792, and a melt index (MI) as measured by ASTM D-1238 at 190 °C/2.16 kg from 0.20 g/10 minutes to 1.5 g/10 minutes. The polyethylene based plastomer has a logM_25% of an upper 25% of a GPC quadrant having a value of 5.1 to 5.7, an intermediate molecular weight distribution (Mw/Mn) of 2.5 to 3, a Mz/Mw value of 2 to 2.5, a Comonomer Distribution Constant value from 60 to 400 and a single SCBD peak between 40-85 °C with a mass fraction of less than 3% above 85 °C as determined by CEF, and a ZSVR value from 1.0 to 5.5. The multilayer thermoplastic film is biaxially stretched at a temperature of 60 °C to 120 °C with a blow-up ratio from 2:1 to 10:1.