Thermoplastic foam with concomitant expansion and curing

Abstract

A thermally expandable composition, includes between 20 and 85 wt.-% of least one thermoplastic polymer P cross-linkable by radical reaction, between 2 and 15 wt.-% of at least one azo radical initiator I, optionally up to 25 wt.-% of at least one adhesion promoter AD, up to 10 wt.-% of at least one tackifier T, up to 2.5 wt.-% of at least one antioxidant AO, and up to 2.5 wt.-% of at least one polyacrylate AC, having a molecular weight of less than 2,500 g/mol, wherein all individual amounts are based on the total composition before expansion. The thermally expandable composition is free of commonly used blowing agents such as azodicarbonamide, but shows excellent properties in terms of expansion stability over a wide temperature range between 120° C. and 200° C. and is especially suitable for baffle and/or reinforcement elements, e.g. in automotive manufacturing.

Dependencies are inferred from the claim text.