Self-assembly of dual-responsive amphiphilic POEGMA-b-P4VP-b-POEGMA triblock copolymers: effect of temperature, pH, and complexation with Cu2+

Autor(es)

Zanata, Daniela de Morais ^[1] ; Felisberti, Maria Isabel ^[1]

Afiliação do(s) autor(es)

^[1] Univ Campinas UNICAMP, Inst Chem, POB 6154, BR-13083970 Campinas, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: Polymer Chemistry; v. 12, n. 32 JUL 2021.
• Citações Web of Science: 0

Resumo

Amphiphilic and stimuli-responsive triblock copolymers are an important class of smart materials due to their low critical micellar concentration in solution and capacity of self-assembly into different structures depending on the environment. In this context, the synthesis of a thermo-responsive poly(oligo(ethylene glycol) methyl ether methacrylate) (POEGMA) macro-RAFT using S,S `-bis(alpha,alpha `-dimethylacetic acid) trithiocarbonate (CMP) as a RAFT agent, followed by copolymerization with a pH-responsive poly(4-vinyl pyridine) (P4VP) is reported. The thermo- and pH responsiveness and critical micellar concentration of the POEG(x)MA(y)-b-P4VP(z)-b-POEG(x)MA(y) copolymers in aqueous solutions were investigated by dynamic light scattering. Cryo-TEM images showed that the POEG(5)MA(24)-b-P4VP(36)-b-POEG(5)MA(24) copolymers self-assemble as spherical and interconnected micelles depending on the composition and environmental conditions. Nanostructures with a hydrodynamic radius (R-H) between 15 and 300 nm are formed. These nanostructures can encapsulate hydrophobic molecules, such as Nile red at pH >= 7 and 25 degrees C. Finally, the P4VP blocks of the triblock copolymer coordinate with Cu2+, generating a thermo- and pH-responsive nanogel whose R-H reduces from 90 to 25 nm by a thermo- or pH-induced deswelling. (AU)

• Processo FAPESP: 15/25406-5 - Organizando a matéria: colóides formados por associação de surfactantes, polímeros e nanopartículas
• Beneficiário: Watson Loh
• Modalidade de apoio: Auxílio à Pesquisa - Temático
• Processo FAPESP: 17/24938-9 - Copolímeros tribloco multiresponsivos baseados em poli[metacrilato de oligo(etileno glicol) metil éter] e poli(4-vinil piridina): síntese e propriedades em solução
• Beneficiário: Daniela de Morais Zanata
• Modalidade de apoio: Bolsas no Brasil - Doutorado