| Autor: |
Ray, Biswajit, Isobe, Yutaka, Kamigaito, Masami, Habaue, Shigeki, Okamoto, Yoshio |
| Předmět: |
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| Zdroj: |
Polymer Journal; 2004, Vol. 36 Issue 9, p728-736, 9p, 4 Diagrams, 6 Charts, 2 Graphs |
| Abstrakt: |
A novel radical initiating system -- rare-earth metal triflate [Y(OTf)3, Yb(Otf) 3, Lu(OTf) 3, Sc(OTf) 3] and alkyl halide containing α-esters (ethyl 2-bromoisobutyrate and ethyl 2-bromopropionate) or α-amide (N,N-dimethyl-2-bromo-2-methylpropanamide) was used for the stereocontrolled radical polymerization of N-isopropylacrylamide (NIPAM). The Lewis acids serve a dual role as the promoter of the radical initiation and the controller of the stereospecific polymerization. The effects of the Lewis acid type and concentration, the initiator type and concentration, solvents, and temperature on the polymerization of NIPAM have been reported. The chain-end structure of the resulting polymer was determined by ¹H NMR. We also extended this initiating system for the polymerization of N,N-dimethylacrylamide, styrene, n-butyl acrylate, and methyl methacrylate. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Supplemental Index |
| Externí odkaz: |
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