MORPHOLOGY AND THERMOMECHANICAL PROPERTIES OF LATEX FILMS

Latex films involve polymers, copolymers and (or) polymer blends, with more or less complex morphologies. First of all, the mechanical behavior of their amorphous polymeric component is considered. A theoretical approach, which relates macroscopic behavior to molecular processes, is used to model ifs dynamic mechanical properties and also plastic behavior. Then, in the case of heterogeneous films, we propose that information about the morphology of samples can be deduced from a comparison of their measured viscoelastic properties with the corresponding properties calculated for a suitable model. After a brief review of the theoretical approaches for the mechanical behavior of multiphase systems, we show the validity of the procedure in the case of latex films obtained from different copolymerization pathways. Thus, it is possible (a) to get information about the morphology of binary systems, (b) to determine the stability of the morphology, and (c) to characterize a third phase as an interphase between nodules and matrix. High stress-strain behavior is discussed in the case of latex films reinforced with nanoparticles of silica or with cellulose whiskers.