Authors: Qing Miao Yong Jin Yang Dong Zhifeng Cao Biao Zhang
Publish Date: 2010/02/02
Volume: 17, Issue: 6, Pages: 911-921
Abstract
A novel series of nonionic bolaamphiphiles—polyurethane amphiphilic block copolymers were synthesized by addition polymerization Their chemical structures were characterized using FTIR and 1HNMR spectra The critical micelle concentration was determined by surface tensiometer and UVvis absorption spectra The surface behaviors of copolymers at air/water interface were also investigated including the effects of concentration molecular structure electrolytes and rest time The results show that these bolaform polyurethane amphiphilic block copolymers exhibited excellent surface activity PU34 could attain surface tension as low as 356 mN m−1 According to the images of Transmission Electron Microscopy TEM the copolymers could selfassemble starlike aggregates comprised of hydrophobic block PPO surrounded by hydrophilic block PEO Moreover variation of concentration the weight fraction of the hydrophilic block fphil and the molecular weight of the copolymers could lead to the transformation of micelle or premicelle morphology This provides a new and simple way to obtain nanoparticles with control over structure on the nanometer scaleThe research is supported by National Natural Science Foundation of China NSFC No20874102 and Project of Science and Technology Commission of Jiaxing No2007A22018 and Ningbo No2006B100056 of Zhejiang We are also thankful to Dr Yujun Feng for the surface tension measurements
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