Tuning the Thermoresponsivity of Amphiphilic Copolymers via Stereocomplex Crystallization of Hydrophobic Blocks.
Xiaohua ChangHailiang MaoGuorong ShanYongzhong BaoPengju PanPublished in: ACS macro letters (2019)
Thermoresponsive polymers that exhibit a cloud point temperature ( T cp ) are an important class of stimuli-responsive polymers that have great potential for biomedical applications. Precise tuning of the T cp is of fundamental importance for designing thermoresponsive polymers. However, tuning the T cp generally requires sophisticated control over the chemical and assembled structures of thermoresponsive polymers. Here, we report a simple yet effective method to tune the T cp of thermoresponsive polymers only by mixing and varying the mixing ratios of amphiphilic copolymer pair that contains l- and d-configured hydrophobic blocks in a dilute solution. Stereocomplex (SC) crystallization of the l- and d-configured blocks led to form core-shell micelles with a larger size, a bigger core, and a higher aggregation number, which facilitated the intermicellar aggregation upon heating due to improved intermicellar attractions. SC crystallization of the hydrophobic blocks improved the separation efficacy of the thermoresponsive copolymers for removal of hydrophobic pollutants from water.