Controlling crystallization morphology of semi-crystalline block polymer by photo-triggered immiscible phase aggregation

This work presents a novel strategy of performing a reversible microcrystalline-spherulite morphology transition based on photo-triggered immiscible phase aggregation in semi-crystalline block polymer. We propose that by assembling or disintegrating immiscible photo-active aggregates during melt crystallization under illuminations, end-to-end distance R of the photo-inactive semi-crystalline polymer chains can be adjusted to generate high-entropy state, R< R ₀ or low-entropy state, R > R ₀. Thus, the corresponding entropic effect influences chain nucleation and can be used to control crystallization morphologies. Besides, photo-tunable mechanical and electrical properties can be also simultaneously endowed. Promising potential applications of this study for optical patterning, memory materials and solid-state electrochemistry can be anticipated. (paper)