ABSTRACT
This chapter explores polymer properties that have been discussed in terms of cohesion parameters. Koenhen and Smolders examined several of these correlations for polymers, using relationships obtained from studies of nonpolymeric liquids. It is reasonable to expect correlations to exist between the observed mechanical properties of polymers and their cohesion parameters. Polymers are viscoelastic, having the characteristics of either elastic materials or of viscous flowing materials, depending on the time-scale of the perturbation and on the temperature. The tests commonly carried out on polymers are stress-strain test, stress relaxation tests, creep tests, and dry crazing tests. The nature of interaction with polymers of plasticizers, whether “primary” (solvent type) or “secondary” (nonsolvent type), may be characterized by their cohesion parameters. Low-volatility plasticizers used in commercial plastics have a long-lasting effect on polymer properties, but volatile liquids can have a similar effect on a short-term basis.
