通过核磁共振氢谱研究尿素与普朗尼克嵌段共聚物的相互作用。

Interaction of urea with pluronic block copolymers by 1H NMR spectroscopy.

作者信息

Ma Jun-he, Guo Chen, Tang Ya-lin, Chen Lin, Bahadur P, Liu Hui-zhou

机构信息

Laboratory of Separation Science and Engineering, Institute of Process Engineering, Graduate School of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing 100080, People's Republic of China.

出版信息

J Phys Chem B. 2007 May 17;111(19):5155-61. doi: 10.1021/jp070887m. Epub 2007 Apr 17.

DOI:10.1021/jp070887m

PMID:17439172

Abstract

Solution 1H NMR techniques were used to characterize the interaction of urea with poly(ethylene oxide)-poly(propylene oxide)-poly(ethylene oxide) (PEO-PPO-PEO) triblock copolymers. The urea was established to interact selectively with the PEO blocks of the block copolymer, and the interaction sites were found not to change with increasing temperature. Such interactions influence the self-assembly properties of the block copolymer in solution by increasing the hydration of the block copolymers and stabilizing the gauche conformation of the PPO chain. Therefore, urea increases the critical micellization temperature (CMT) values of PEO-PPO-PEO copolymers, and the effect of urea on the CMT is more pronounced for copolymers with higher PEO contents and lower for those with increased contents of PPO segments.

摘要

采用溶液¹H NMR技术表征尿素与聚（环氧乙烷）-聚（环氧丙烷）-聚（环氧乙烷）（PEO-PPO-PEO）三嵌段共聚物的相互作用。已证实尿素与嵌段共聚物的PEO链段选择性相互作用，且相互作用位点不随温度升高而改变。这种相互作用通过增加嵌段共聚物的水合作用并稳定PPO链的gauche构象来影响嵌段共聚物在溶液中的自组装性能。因此，尿素提高了PEO-PPO-PEO共聚物的临界胶束化温度（CMT）值，对于PEO含量较高的共聚物，尿素对CMT的影响更为显著，而对于PPO链段含量增加的共聚物，这种影响则较小。