Knowledge Management System Of Institute of process engineering,CAS
| Association behavior of PEO-PPO-PEO block copolymers in water or organic solvent observed by FTIR spectroscopy | |
| Alternative Title | Mol. Simul. |
| Su, YL; Liu, HZ; Guo, C; Wang, J | |
| 2003-12-01 | |
| Source Publication | MOLECULAR SIMULATION
 |
| ISSN | 0892-7022 |
| Volume | 29Issue:12Pages:803-808 |
| Abstract | 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.; 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. |
| Keyword | Fourier Transform Infrared Spectroscopy Peo-ppo-peo Block Copolymers Critical Micellization Concentration Critical Micellization Temperature |
| Subtype | Article |
| WOS Headings | Science & Technology ; Physical Sciences |
| DOI | 10.1080/0892702031000121888 |
| URL | 查看原文 |
| Indexed By | ISTP ; SCI |
| Language | 英语 |
| WOS Keyword | ANGLE NEUTRON-SCATTERING ; AQUEOUS-SOLUTIONS ; MICELLE FORMATION ; AGGREGATION BEHAVIOR ; LATTICE THEORY ; TEMPERATURE ; MICELLIZATION ; HYDRATION ; SOLUBILIZATION ; DYNAMICS |
| WOS Research Area | Chemistry ; Physics |
| WOS Subject | Chemistry, Physical ; Physics, Atomic, Molecular & Chemical |
| WOS ID | WOS:000186010000015 |
| Citation statistics | |
| Document Type | 期刊论文 |
| Version | 出版稿 |
| Identifier | http://ir.ipe.ac.cn/handle/122111/5268 |
| Collection | 研究所（批量导入） |
| Affiliation | Chinese Acad Sci, Inst Proc Engn, State Key Lab Biochem Engn, Young Scientist Lab Separat Sci & Engn, Beijing 100080, Peoples R China |
| Recommended Citation 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. |
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| Association behavior（125KB） | 限制开放 | CC BY-NC-SA | Application Full Text | |||
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