Polarized Light: Qualitative Microscopy

Abstract

This chapter is concerned with the uses that are made of polarized light in the study of polymer structure. These uses are determined by the type of polymer under examination, i.e. whether it is semicrystalline or amorphous. Semicrystalline polymers crystallize from the melt, in the absence of significant shear or elongational flow, in the form of a characteristic structural entity called a spherulite. Variation in size, shape and type of spherulite with temperature and flow conditions during crystallization is a powerful diagnostic indicator of the change in the factors throughout a complex moulded product. Hence the study of spherulitic texture in these materials will reveal the structural changes caused by varying production conditions. In fact the study of sefnicrystalline polymers by polarized light methods constitutes a large proportion of all light microscope studies on polymers.