Anisotropy of optical and mechanical properties of stretched low density polyethylene

Summary Parallel measurements of IR dichroism, birefringence and microhardness anisotropy of drawn low density polyethylene films have been carried out. The angle α between the dipole moment vector of the IR band at 1367 cm⁻¹ and the chain axis has a value of 50°. The longitudinal and transverse moduli of the drawn samples, measured by microhardness indentations, increase as the draw ratio increases after passing through a minimum for a draw ratio of around 1.5. Received: 27 April 1998/Revised version: 22 July 1998/Accepted: 22 July 1998