Effect of anions, urea and aggregation state on the thermal behavior of PDMAEMA-based polymers

Author(s)

Ferreira Silva, Igor Wallace ; Souza, Valdomiro Vagner ; Florenzano, Fabio Herbst

• Document type: Journal article
• Source: COLLOID AND POLYMER SCIENCE; v. 300, n. 10, p. 5-pg., 2022-08-04.

Abstract

Fine-tuning the thermal behavior of copolymer vesicles is useful to generate systems that perform a task triggered by a specific change in temperature. This work studies how urea and different anions affect the lower critical solution temperature (LCST) behavior of two polymeric materials based on poly(2-dimethylaminoethyl methacrylate), PDMAEMA: a homopolymer and a block copolymer (PDMAEMA-b-PS) in the non-aggregated and aggregated states, respectively, in aqueous media. The copolymer vesicles presented higher LCST than homopolymer systems, under the same conditions, as a result of the aggregation state. Moreover, concentrated urea solutions increase the cloud point temperature, T-cp, for both materials. Thiocyanate affects more thermoresponsiveness for both the homopolymer and the copolymer systems than chloride. Urea affects the ion condensation on the surface of the vesicles or on the solubilized chains leading to the anions behaving similarly (small difference in the affinity to the positively charged surface in the presence of the additive). (AU)

• FAPESP's process: 13/08166-5 - Interfacial chemistry: drugs, peptides and ezymes interactions with membrane models
• Grantee: Iolanda Midea Cuccovia
• Support Opportunities: Research Projects - Thematic Grants