Double stimuli-responsive behavior of graft copolymer with polyimide backbone and poly(N,N-dimethylaminoethyl methacrylate) side chains

作者：Filippov A P; Belyaeva E V; Zakharova N V; Sasina A S^*; Ilgach D M; Meleshko T K; Yakimansky A V

来源：Colloid and Polymer Science, 2015, 293(2): 555-565.

DOI：10.1007/s00396-014-3441-3

• Graft copolymers
• Atom transfer radical polymerization
• Thermo- and pH-sensitive polymers
• Static and dynamic light scattering
• Lower critical solution temperature
• Aggregation

Comblike block copolymer having a polyimide backbone and poly(N,N-dimethylaminoethyl methacrylate) side chains, i.e., PI-g-PDMAEMA, was prepared through the "grafting from" method using (N,N-dimethylaminoethyl methacrylate) polymerization on a polyimide multicenter macroinitiator by atom transfer radical polymerization (ATRP) mechanism. Its molar mass characteristics were determined in chloroform solution using hydrodynamic methods. PI-g-PDMAEMA is a relatively loose molecular brush with the substitution degree z = 0.44. The behavior of PI-g-PDMAEMA in aqueous solutions at a concentration 0.015 g cm(-3) was studied by light scattering within a pH interval from 2.1 to 12.4. The temperature dependences of light scattering intensity and hydrodynamic sizes of dissolved species were obtained. Synthesized copolymer shows clearly temperature and pH responsiveness. PI-g-PDMAEMA is thermo-sensitive at pH a parts per thousand yenaEuro parts per thousand 8.9. The pH growth is accompanied by a decrease in the phase transition temperature and an increase in the width of the phase transition interval and hydrodynamic radii of the micellar aggregates and large loose aggregates.

• 出版日期2015-2