Depending on latex properties, solvent evaporation or particle deformation may rate-limit the process of wet film formation. Contrary to dry film formation, wet film formation is aided by the hydroplasticized state of the polymer. Another advantage of wet film formation is the appearance of capillary forces directed towards particle deformation. As a result hydrophilic latices may film-form at temperatures significantly lower than T g of the dry film, which is of practical significance. Cracks originate from stress built up during densification of coatings and limit their application.
Superficial cracks result from stresses due to the deformation of particles within the skin.
Cracks may also form at later stages and then proceed throughout the film. The spatial frequency and direction of the cracks depend on drying conditions. Immediate release of the stress through plastic shrinkage normal to the film plane yields perfect, crack-free films. In this case, water evaporation is the rate-limiting process for film formation. This project aims, through a combination of different scientific disciplines and an innovation of appropriate techniques, to develop a deeper understanding of the effects the nature of latex and the drying conditions have on film formation and final properties.