Characterisation of Filled Compounds

Frequently, fillers such as hard minerals or soft rubbers are combined with polymers to modify mechanical properties, such as elastic modulus or resistance to crack propagation 

Of great relevance to filled polymer formulations, is the uniformity of particle distribution, the degree of dispersion achieved and the interaction between the filler and matrix phases. Other influencing factors include the presence of micro-porosity, reductions in the molecular mass of the polymer, and changes to the form and level of crystallinity in semi-crystalline thermoplastics. It can be beneficial to consider the measurement of quality in filled polymers in terms of characterising these structural parameters, since, as will be considered later, often an identifiable relationship exists with the compounding route used. 

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