Association behavior of PEO-PPO-PEO block copolymers in water or organic solvent observed by FTIR spectroscopy
文献类型：期刊论文
| 作者 | Su, YL; Liu, HZ; Guo, C; Wang, J |
| 刊名 | MOLECULAR SIMULATION
 |
| 出版日期 | 2003-12-01 |
| 卷号 | 29期号:12页码:803-808 |
| 关键词 | Fourier transform infrared spectroscopy PEO-PPO-PEO block copolymers critical micellization concentration critical micellization temperature |
| ISSN号 | 0892-7022 |
| 其他题名 | Mol. Simul. |
| 中文摘要 | Fourier transform infrared (FTIR) spectroscopy is applied to investigate the association behavior of poly(ethylene oxide)-poly(propylene oxide)-poly(ethylene oxide) (PEO-PPO-PEO) block copolymers in water or organic solvent as a function of temperature. In aqueous solutions, when the temperature approaches the critical micellization temperature, the antisymmetric C-H stretching vibration of methyl groups shifts toward lower wavenumber. It indicates that the methyl groups are experiencing a progressively less polar environment and the interaction of the methyl groups with water molecules is weakened by heat. At higher temperatures, the symmetric deformation vibration of methyl groups is composed of two bands, which are related to hydrated and dehydrated state. The proportion of the dehydrated methyl groups of Pluronic polymers increases with an increase of temperature, which means the exclusion of water from the micelle cores and formation of micelles with a denser PPO core at higher temperatures. A more hydrophobic Pluronic polymer would form a micelle in water with a higher proportion of dehydrated methyl groups. No changes in FTIR spectra correspond to temperature dependent gelation of Pluronic F127 in water. Based on FTIR spectroscopic results of Pluronic P104, the PPO blocks are hydrated only in a condition of lower temperature and lower polymer concentration. In the hydration process, PEO blocks would be hydrated preferentially where H 2 O molecules are bound easily to PEO segments. The water-induced reverse micelle formation of Pluronic L92, in p -Xylene solution has also been investigated by FTIR spectroscopic technique. The reason of reverse micelle formation is explained by the strengthening of the intermolecular interactions of copolymers, which was originated from the interactions of solubilized water. |
| 英文摘要 | Fourier transform infrared (FTIR) spectroscopy is applied to investigate the association behavior of poly(ethylene oxide)-poly(propylene oxide)-poly(ethylene oxide) (PEO-PPO-PEO) block copolymers in water or organic solvent as a function of temperature. In aqueous solutions, when the temperature approaches the critical micellization temperature, the antisymmetric C-H stretching vibration of methyl groups shifts toward lower wavenumber. It indicates that the methyl groups are experiencing a progressively less polar environment and the interaction of the methyl groups with water molecules is weakened by heat. At higher temperatures, the symmetric deformation vibration of methyl groups is composed of two bands, which are related to hydrated and dehydrated state. The proportion of the dehydrated methyl groups of Pluronic polymers increases with an increase of temperature, which means the exclusion of water from the micelle cores and formation of micelles with a denser PPO core at higher temperatures. A more hydrophobic Pluronic polymer would form a micelle in water with a higher proportion of dehydrated methyl groups. No changes in FTIR spectra correspond to temperature dependent gelation of Pluronic F127 in water. Based on FTIR spectroscopic results of Pluronic P104, the PPO blocks are hydrated only in a condition of lower temperature and lower polymer concentration. In the hydration process, PEO blocks would be hydrated preferentially where H 2 O molecules are bound easily to PEO segments. The water-induced reverse micelle formation of Pluronic L92, in p -Xylene solution has also been investigated by FTIR spectroscopic technique. The reason of reverse micelle formation is explained by the strengthening of the intermolecular interactions of copolymers, which was originated from the interactions of solubilized water. |
| WOS标题词 | Science & Technology ; Physical Sciences |
| 类目[WOS] | Chemistry, Physical ; Physics, Atomic, Molecular & Chemical |
| 研究领域[WOS] | Chemistry ; Physics |
| 关键词[WOS] | ANGLE NEUTRON-SCATTERING ; AQUEOUS-SOLUTIONS ; MICELLE FORMATION ; AGGREGATION BEHAVIOR ; LATTICE THEORY ; TEMPERATURE ; MICELLIZATION ; HYDRATION ; SOLUBILIZATION ; DYNAMICS |
| 收录类别 | ISTP ; SCI |
| 原文出处 | |
| 语种 | 英语 |
| WOS记录号 | WOS:000186010000015 |
| 公开日期 | 2013-11-08 |
| 版本 | 出版稿 |
| 源URL | [http://ir.ipe.ac.cn/handle/122111/5268]  |
| 专题 | 过程工程研究所_研究所（批量导入） |
| 作者单位 | Chinese Acad Sci, Inst Proc Engn, State Key Lab Biochem Engn, Young Scientist Lab Separat Sci & Engn, Beijing 100080, Peoples R China |
| 推荐引用方式 GB/T 7714 | Su, YL,Liu, HZ,Guo, C,et al. Association behavior of PEO-PPO-PEO block copolymers in water or organic solvent observed by FTIR spectroscopy[J]. MOLECULAR SIMULATION,2003,29(12):803-808. |
| APA | Su, YL,Liu, HZ,Guo, C,&Wang, J.(2003).Association behavior of PEO-PPO-PEO block copolymers in water or organic solvent observed by FTIR spectroscopy.MOLECULAR SIMULATION,29(12),803-808. |
| MLA | Su, YL,et al."Association behavior of PEO-PPO-PEO block copolymers in water or organic solvent observed by FTIR spectroscopy".MOLECULAR SIMULATION 29.12(2003):803-808. |
入库方式： OAI收割
来源：过程工程研究所
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