Short PET and PA fibre composites based on LDPE and HDPE matrices - Morphology-behaviour relationship

The effect of unmodified and azide-modified short poly(ethylene terephthala te) (PET) and polyamide 66 (PA) fibres on the mechanical properties of ther moplastic composites based on low density (LDPE) and high density polyethyl ene (HDPE) matrices was investigated. The results have shown that both orga nic fibres are suitable reinforcements for LDPE and HDPE matrices. The weak est the matrix the strongest is the reinforcing effect of the fibres, so, t he reinforcing effect of the fibres is more sensible in the LDPE matrix, p- (Azidosulfonyl)benzoyl azide is an adequate coupling agent for both fibres, especially for PET fibres. A better adhesion at the fibre/matrix interface of the composites has been observed by scanning electron microscopy, mainl y in the PET-filled LDPE.