COPOLYETHER ESTER COMPOSITION AND AIR BAG COVER MADE THEREFROM

摘要

The invention relates to a copolyether ester composition consisting essentially of a blend of (a)at least one copolyether ester consisting essentially of polyester hard segments and aliphatic polyether soft segments and having a hardness lower than 46 Shore D; and (b)at least one polyester with hardness higher than 60 Shore D, which polyester is compatible with the polyester hard segments of component (a); wherein components (a) and (b) are present in a mass ratio of 9/1 to 1/9, which composition has a modulus at -40°C lower than 500 MPa and at 190 °C higher than 10 MPa, as measured with a Dynamic Mechanical Spectrometer on a test-sample dynamically elongated at 1 Hz following ASTM D5026, and a melt viscosity, as measured at 240 °C and at shear rate 1 s<-1>, of at least 1 kPa.s. An advantage of this composition is that an air bag cover moulded thereof, passes an air bag deployment test at -35 +/- 2°C, also if the air bag cover is painted. The invention also relates to a process for preparing such a copolyether ester composition and to a process for making an air bag cover from such composition. The invention also relates to an air bag system comprising an air bag 20 cover obtainable by the latter process, which system successfully passes a deployment test at -35 +/- 2°C.