Comparative study of orientation in hot-drawn poly(ethylene terephthalate) by means of refractive index and microhardness measurements



Refractive index and microhardness of drawn samples of poly(ethylene terephthalate) were measured by means of an Abbé refractometer and a microindentation hardness equipment. The optical and mechanical anisotropies determined from these measurements were compared with the birefringences obtained by using compensators and fitted to the affine deformation scheme, showing that microhardness anisotropy is a suitable technique for studying the overall orientation in polymers.