SYNTHESES OF HIGHLY EFFECTIVE NITROXIDE RADICALS IN LIVING RADICAL POTYMERIZATION
Project/Area Number |
12450376
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Research Category |
Grant-in-Aid for Scientific Research (B)
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Allocation Type | Single-year Grants |
Section | 一般 |
Research Field |
高分子合成
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Research Institution | OSAKA CITY UNIVERSITY |
Principal Investigator |
MIURA Yozo OSAKA CITY UNIVERSITY, DEPARTMENT OF APPLIED CHEMISTRY, GRADUATE SCHOOL OF ENGINEERING, PROFESSOR, 大学院・工学研究科, 教授 (50047312)
|
Project Period (FY) |
2000 – 2001
|
Project Status |
Completed (Fiscal Year 2001)
|
Budget Amount *help |
¥2,700,000 (Direct Cost: ¥2,700,000)
Fiscal Year 2001: ¥2,700,000 (Direct Cost: ¥2,700,000)
|
Keywords | Living Radical Polymerization / Controlled Radical Polymerization / Nitroxide / star Polymer / Block Copolymer / Polydispersity / ブロックポリマー / スチレン / TEMPO |
Research Abstract |
2,6-di-spirohexylpiperidyl-N-oxyl (1) and 2-spirofeptylpipenridy-N-oxyl (2) were synthesized and their abilities to control the radical polymerization of styrene (St) were investigated. The radical polymerizations of St mediated by 1 and 2 were carried out at 70-90 ℃, and the polymerization systems gave poly (St) with low polydispersity indexes below 1.3, indicationg that the polymerization proceeds in the living fashion, even at 70-90 ℃. This is the first successful low-temperature living radical polymerization of St. Random copolymerization of St and BA and St with methyl mathacrylate (MMA) were carried out at 80 ℃ in the presence of 1 or 2 to evaluate the ability of to control well-controkked random copolymers. When the initial molar ratio of St is more than 0.30, the copolymerizations were well controlled to give copolymers with low polydispersity indexes. On the basis of the above results, it is concluded that nitroxides 1 and 2 are much more excellent in the ability to control th
… More
e polymerization of St and random copolymerization of St and BA and St and MMA than TEMPO. Well-controlled three-am and six-arm star poly (styrne)s were successfully prepared using the multifunctional initiators having three and six alkoxyamine moieties. In this study we estabished the general procedure for the preparation of a 6-alkoxyamine moiety bearing dendorimer. We now succeeded in the preparation of a 12-alkoxyamine moiety bearing dendorimer. Well-controlled poly (siloxane) -b-poly(St)s with a low polydispersity index were successfully prepared by using an alkoxyamine having an alkyllithium moiety. Thus, hexamethylcyclic-trisiloxane was polymerized with the butyllithium moiety, and St was polymerized with the resultant macroininitaor having the alkoxyamine moiety. The block copolymer obtained contains no homopolymers and its polydispersity index was below 1.3. This conventional procedure will provide an excellent method for the preparation of block copolymers by the combination of anion and radical polymerization Less
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Report
(3 results)
Research Products
(12 results)