Synthesis of Stereoregular Living Polymers from Substituted Acetylenes and Design of Polymerization Catalysts
Project/Area Number |
05650897
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Research Category |
Grant-in-Aid for General Scientific Research (C)
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Allocation Type | Single-year Grants |
Research Field |
高分子合成
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Research Institution | KYOTO UNIVERSITY |
Principal Investigator |
MASUDA Toshio Kyoto University, Dept. of Polymer Chemistry, Professor, 工学部, 教授 (60026276)
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Project Period (FY) |
1993 – 1994
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Project Status |
Completed (Fiscal Year 1994)
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Budget Amount *help |
¥2,200,000 (Direct Cost: ¥2,200,000)
Fiscal Year 1994: ¥900,000 (Direct Cost: ¥900,000)
Fiscal Year 1993: ¥1,300,000 (Direct Cost: ¥1,300,000)
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Keywords | Substituted Acetylene / Stereoregular Polymer / Living Polymer / Catalyst Design / tert-Butylacetylene / (o-Methylphenyl) acetylene / Stereospecific Living Polymerization / Molybdenum Catalyst / (ロ-メチルフェニル)アセチレン / 炭素13核磁気共鳴 |
Research Abstract |
The molecular weight distribution (MWD) and steric structure of a polymer should be well defined so that the polymer would exhibit excellent properties and functions. The present study deals with the synthesis of stereoregular living polymers from substituted acetylenes and development of novel catalysts useful for such purposes. 1. Stereospecific living polymerization of tert-butylacetylene (tBA) by Mo-based catalysts-The polymerization of tBA by the MoOCl_4-n-Bu_4Sn-EtOH (1 : 1 : 1) catalyst led to living and stereoregular polymers with narrow MWDs (Mw/Mn=1.12 ; cis 97%) . The living nature of this polymerization was confirmed by the fact that, in toluene at 0 and -30゚C,the Mn of the polymer increases in direct proportion to monomer consumption, while the MWD remains narrow. The cis content of polymer was evaluated by ^<13>C NMR spectroscopy. Similar but somewhat inferior results were obtained with the MoCl_5-n-Bu_4Sn-EtOH (1 : 1 : 1) system (Mw/Mn=1.24 ; cis 90%) . 2. Synthesis of a cis-rich, living poly [ (o-methylphenyl) acetylene] (oMePA) -Polymerization of oMePA by MoOCl_4-n-Bu_4Sn-EtOH catalyst in toluene at 0゚C provided a cis-rich living polymer ; cis 77%, Mw/Mn=1,21. The polymerization at-30゚C gave results similar to those for 0゚C,whereas the polymer obtained at 30゚C exhibited a broader MWD and a lower cis content. 3. Development of MoOCl_4-based new catalyst systems for living polymerization-In this study, we tried to develop new catalyst systems for the living metathesis polymerization using Et_3Al as cocatalyst. [o- (Trifluoromethyl) phenyl] acetylene was used as monomer, and polymerizations were carried out in anisole at 30゚C.Eventually, a polymer with very narrow MWD (Mw/Mn=1.02) could be obtained by use of MoOCl_4-Et_3Al-EtOH at 1 : 1 : 4 ratio.
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Report
(3 results)
Research Products
(9 results)