Introduction

This book deals with the properties of filled polymers, i.e. mixtures of macromolecular materials with finely divided substances, with respect to established scientific aspects and industrial developments. So-called (polymer) composites, that consist of long fibers impregnated with resins, such as glass fibers reinforced polyesters or carbon fibers reinforced epoxy resins, are not within the subject of this book. Filled polymers discussed hereafter are heterogeneous systems such that, during processing operations, the polymer and the dispersed filler flow together. In other words, filled polymers are macroscopically coherent masses that exhibit interesting physical, mechanical, and/or rheological properties, often peculiar, but always resulting from interactions taking place between a matrix (the polymer) and a dispersed phase (the filler). It follows obviously that filled polymers have to be prepared through mixing operations, generally complex and requiring appropriate machines, in such a manner that a thorough dispersion of filler particles is achieved.