中國醫藥大學機構典藏 China Medical University Repository, Taiwan:Item 310903500/1190
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    Please use this identifier to cite or link to this item: http://ir.cmu.edu.tw/ir/handle/310903500/1190


    Title: GPC Observations of Branching Effects in Anionic Polymerization of Methyl Methacrylate:A Preliminary Study
    Authors: 蔡育勳(Yuhsin Tsai)*;(Jyh-Horng Wu);蔡輔仁(Fuu-Jen Tsai)
    Contributors: 中醫學院中國醫學研究所
    Keywords: anionic polymerization;gel permeation chromatography;branching reaction;polymethyl methacrylate;butyllithium
    Date: 2009-02
    Issue Date: 2009-08-19 16:36:04 (UTC+8)
    Abstract: The anionic polymerization of methyl methacrylate was performed in tetrahydrofuran (THF) at -78°C, using sec-butyllithium/1,1-diphenylethylene (DPE) as the initiation system. The effects of polymerization time and initiator concentration on the branching reaction were studied. High vacuum was used to prevent contamination during the polymerization. Gel permeation chromatography (GPC) was used to characterize the branching effect qualitatively. Experimental results indicated that the monomer conversion reached more than 98% in a polymerization time of 10 min. The branching reaction occurred after high monomer conversion, resulting in a tail of high molecular weight in the GPC trace. This branching effect, observed by GPC, increased with polymerization time. Rapid termination was thus probably required immediately after all of the monomer was consumed in the preparation of a well-defined PMMA without a high-molecular-weight tail in this diphenylbutylllithium/THF/-78°C system.
    Relation: JOURNAL OF APPLIED POLYMER SCIENCE 111(3):2099~2103
    Appears in Collections:[Graduate Institute of Chinese Medical Science] Journal articles

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