Temperature and anion responsive self-assembly of ionic liquid block copolymers coating gold nanoparticles

• Published in: Frontiers of materials science Vol. 10; no. 2; pp. 178 - 186
• Main Authors: LI, Junbo, ZHAO, Jianlong, WU, Wenlan, LIANG, Ju, GUO, Jinwu, ZHOU, Huiyun, LIANG, Lijuan
• Format: Journal Article
• Language: English
• Published: Beijing Higher Education Press 01.06.2016
• Subjects: Au纳米粒子; block copolymer; Chemistry and Materials Science; dual stimuli-responsive; gold nanoparticles (Au NPs); Materials Science; Research Article; self-assembly; 低临界溶液温度; 可逆加成-断裂链转移; 嵌段共聚物; 离子响应; 离子液体; 自组装行为; 金纳米粒子; block copolymer; self-assembly; dual stimuli-responsive; gold nanoparticles (Au NPs)
• ISSN: 2095-025X; 2095-0268
• DOI: 10.1007/s11706-016-0334-z

In this paper, double hydrophilic ionic liquid block copolymers （ILBCs）, poly poly[1-methyl-3-（2-methacryloyloxy propylimidazolium bromine）]-block-（N.isopro. pylacrylamide） （PMMPImB-b-PNIPAAm） was first synthesized by reversible addition- fragmentation chain transfer （RAFT） and then attached on the surface of gold nanoparticles （Au NPs） via a strong gold-sulfur bonding for preparing hybrid nanoparticles （PMMPImB-b-PNIPAAm-@-Au NPs）. The hybrid NPs had a three layers micelle-like structure, including a gold core, thermo-responsive inner shell and anion responsive outer corona. The self-assembling behavior of thermal- and anion-response from shell and corona were respectively investigated by change of temperature and addition of （CF3SO2）2N-. The results showed the hybrid NPs retained a stable dispersion beyond the lower critical solution temperature （LCST） because of the space or electrostatic protecting by outer PMMPImBo However, with increasing concentration of （CF3SO2）2N-, the micellization of self-assembling PMMPImB-b-PNIPAAm-@-Au NPs was induced to form micellar structure containing the core with hydrophobic PMMPImB- （CF3SO2）2N- surrounded by composite shell of Au NPs-PNIPAAm via the anion- responsive properties of ILBCs. These results indicated that the block copolymers protected plasmonic nanoparticles remain self-assembling properties of block copoly- mers when phase transition from outer corona polymer.