On crystalline interfaces in composite materials

The fiber/matrix interactions across the interface in composite materials include a wide range of chemical, mechanical and physical processes, depending on the nature of the constituents in question. In composites of thermoplastic polymer matrices a specific interaction is feasible that results in nucleation and crystallization of a transcrystalline layer on the fiber surface. Such a layer is characterized by a highly ordered structure and different mechanical and physical properties compared to the bulk matrix, and it may generate significant changes in the behavior of the composite material. From the aspect of application the properties of the composite are of prime interest, and thus the question of the effect of transcrystallinity on the composite properties becomes essential. In this paper we scan and review our main observations on a number of specific systems that we have investigated recently, contributing to the accumulation of sufficient relevant data for some meaningful generalizations to be attempted, despite the high compositional variability of composite materials and, in turn, of transcrystallinity.