Development of High Thermal Conductivity and Toughness of Networked Polymers with Liquid Crystal Structure

Abstract

The structure of the highly ordered polymer network formed by liquid crystalline (LC) epoxy resins varies significantly depending on the curing conditions and the chemical structure of the curing agent. Therefore, controlling the alignment of molecular chain with mesogenic groups is a key strategy for improving the thermal conductivity and toughness of the thermosets. In practical applications, the incorporation of fillers is essential. In such composites, it is necessary to consider not only the dispersibility of the fillers but also the influence of the filler–matrix interface on the molecular chain alignment. This review provides a detailed overview of the impact of curing agent structure on molecular alignment of LC epoxy, as well as the influence of fillers and their surface modifications. Furthermore, it presents examples of applying LC epoxy resins to modify high heat-resistant cyanate ester resins, and introduces the properties of LC cyanate esters with mesogenic group.