Remarkable modulus enhancement of polylactide ion gels via network formation induced by a nucleating agent

Ion gels have been obtained by crystallization of polylactide (PLA) in an ionic liquid. The modulus of the resulted ion gels is increased with PLA content in the ionic liquid, whereas ionic conductivity follows an opposite tendency. Isolated spheres, caused by PLA crystallization, are responsible for low modulus in the ion gels with low PLA content. By adding a nucleating agent isolated spheres are transformed into interconnected network due to the increased nucleation density during PLA crystallization in the ionic liquid. It in turn significantly enhances the modulus by more than three orders of magnitude, while ionic conductivity remains nearly intact. [Display omitted] •Ion gel was obtained by PLA crystallization in an ionic liquid.•Low modulus was exhibited by ion gels with isolated PLA spheres.•Adding a nucleating agent transformed spheres into interconnected network.•The modulus was thus enhanced by more than three orders of magnitude.