Phthalonitrile end‐capped polyarylene ether nitrile: crystals embedded in matrix through crosslinking reaction

Abstract

AbstractA novel single‐component composite based on phthalonitrile end‐capped polyarylene ether nitrile (PEN‐Ph) which undergoes a crosslinking reaction combined with crystallization behavior has been prepared successfully by hot compressing. The project focuses on studying the influence of the processing temperature and curing time on the crosslinking reaction and crystallization behavior. Differential scanning calorimetry analysis indicates that the crosslinking degree increases with an increase of processing temperature and curing time. In contrast, the crystallinity increases first and then decreases as the curing time increases, owing to the effect of the restriction of the crosslinking reaction on the crystallization behavior. Thermal polarizing microscope images provide direct evidence for crystal formation as a result of crosslinking reaction. Moreover, through comparative analysis of amorphous and crystallized PEN‐Ph sheets, the conclusion is drawn that the glass transition temperature and mechanical properties are affected by not only the degree of crosslinking but also by the crystallinity. © 2015 Society of Chemical Industry