Preparation and Characterization of Thermoresponsive Copolymers

Abstract

This thesis reports the synthesis of PNIPA-b-PDEA block copolymers using sequential RAFT polymerization in dioxane. Copolymers with different block lengths were successfully prepared and purified, and their molecular weights were characterized using MALDI-TOF mass spectrometry and GPC. The MALDI results confirmed the expected block compositions, while GPC showed relatively narrow molecular weight distributions. A selected set of copolymers was further examined using temperature-dependent DLS to determine their aggregation (LCST-type) temperatures. The results demonstrated that the transition temperature increases with increasing PNIPA content, indicating that PNIPA has a stronger influence on thermoresponsive behavior than PDEA. Overall, the study highlights how block composition and molecular weight affect the solution properties of PNIPA-b-PDEA copolymers.