Ionic liquid as structuring agent of polyamide 11: Influence on the polymorphism and molecular mobility

Abstract

The impact of an imidazolium-based ionic liquid (IL) on the morphology as well as physical structure and molecular mobility of polyamide 11 (PA11) was investigated. A low IL content lead to the formation of the $\gamma$ crystalline phase of PA11, through a fractionated crystallization process promoted by the droplet morphology obtained at the nano to microscale. The thermal and dielectric signatures of IL excess inside the droplets were evidenced. Dynamic mechanical and dielectric analyses also revealed an additional secondary $\beta$ relaxation of PA11 associated with the mobility of its amide groups, as well as important modifications of the PA11 usual mobilities, explained by the complex interactions between the ionic liquid, water molecules and the polymer matrix.