Xue Xiaoqiang, Li Fang, Huang Wenyan, Yang Hongjun, Jiang Bibiao, Zheng Yiliang, Zhang Dongliang, Fang Jianbo, Kong Lizhi, Zhai Guangqun, Chen Jianhai
Key Laboratory of Polymeric Materials of Changzhou City, School of Material Science and Engineering, Changzhou University, Changzhou, Jiangsu, 213164, People's Republic of China.
Macromol Rapid Commun. 2014 Feb;35(3):330-6. doi: 10.1002/marc.201300743. Epub 2013 Dec 6.
The novel hyperbranched poly(methyl acrylate)-block-poly(acrylic acid)s (HBPMA-b-PAAs) are successfully synthesized via single-electron transfer-living radical polymerization (SET-LRP), followed with hydrolysis reaction. The copolymer solution could spontaneously form unimolecular micelles composed of the hydrophobic core (PMA) and the hydrophilic shell (PAA) in water. Results show that the size of spherical particles increases from 8.18 to 19.18 nm with increased pH from 3.0 to 12.0. Most interestingly, the unique regular quadrangular prisms with the large microstructure (5.70 μm in length, and 0.47 μm in width) are observed by the self-assembly of unimolecular micelles when pH value is below 2. Such self-assembly behavior of HBPMA-b-PAA in solution is significantly influenced by the pH cycle times and concentration, which show that increased polymer concentration favors aggregate growth.
通过单电子转移活性自由基聚合（SET-LRP），随后进行水解反应，成功合成了新型超支化聚（丙烯酸甲酯）-嵌段-聚（丙烯酸）（HBPMA-b-PAAs）。该共聚物溶液在水中可自发形成由疏水核（PMA）和亲水壳（PAA）组成的单分子胶束。结果表明，随着pH值从3.0增加到12.0，球形颗粒的尺寸从8.18 nm增加到19.18 nm。最有趣的是，当pH值低于2时，通过单分子胶束的自组装观察到具有大微观结构（长度为5.70μm，宽度为0.47μm）的独特规则四方棱柱。HBPMA-b-PAA在溶液中的这种自组装行为受到pH循环次数和浓度的显著影响，这表明聚合物浓度的增加有利于聚集体的生长。
