Mechanistic insights into the formation of polyion complex aggregates from cationic thermoresponsive diblock copolymers

Hypothesis: The formation of polyion complexes (PICs) comprising thermoresponsive polymers is intended to result in the formation of aggregates that undergo significant structural changes with temperature. Moreover the observed modifications might be critically affected by polymer structure and PICs composition. Experiments: Different block copolymers based on cationic poly(3-acrylamidopropyltrimethylammo nium chloride) and thermoresponsive poly(N-isopropylacrylamide) were synthesized by aqueous RAFT/MADIX polymerization at room temperature. Addition of poly(acrylic acid) in a controlled fashion led to the formation of PICs aggregates. The structural changes induced by temperature were characterized by differential scanning calorimetry, Nuclear Magnetic Resonance spectroscopy and scattering methods.

Automated summary

The study focuses on investigating the structural changes of polyion complexes (PICs) composed of thermoresponsive polymers with temperature variations, and suggests that the polymer structure and PICs composition play a crucial role in the observed modifications.