English  |  正體中文  |  简体中文  |  Items with full text/Total items : 94286/110023 (86%)
Visitors : 21696851      Online Users : 795
RC Version 6.0 © Powered By DSPACE, MIT. Enhanced by NTU Library IR team.
Scope Tips:
  • please add "double quotation mark" for query phrases to get precise results
  • please goto advance search for comprehansive author search
    •  Adv. Search
    Home ‧ Login ‧ Upload ‧ Help ‧ About ‧ Administer Goto mobile version


    Please use this identifier to cite or link to this item: http://asiair.asia.edu.tw/ir/handle/310904400/8632


    Title: GPC observations of branching effects in anionic polymerization of methyl methacrylate: A preliminary study
    Authors: Tsai, Yuhsin;Wu, Jyh-Horng;Tsai, Fuu-Jen
    Contributors: Department of Biotechnology
    Keywords: Acrylic monomers;Chemical reactions;Chromatographic analysis;Chromatography;Esters;Gelation;Gels;Monomers;Polyacrylates;Branching effects;Branching reaction;Butyllithium;C-systems;Gel permeation chromatography;High molecular weights;High vacuums;Initiation systems;Initiator concentrations;Methyl methacrylates;Monomer conversions;Polymerization time;Polymethyl methacrylate;TetrahydrofuranPolymerization;Polymers;Branching effects;Branching reaction;Butyllithium;C-systems;Gel permeation chromatography;High molecular weights;High vacuums;Initiation systems;Initiator concentrations;Methyl methacrylates;Monomer conversions;Polymerization time;Polymethyl methacrylate;Tetrahydrofuran
    Date: 2009
    Issue Date: 2010-04-07 13:17:57 (UTC+0)
    Publisher: Asia University
    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-molecularweight tail in this diphenylbutylllithium/THF/-78°C system. © 2008 Wiley Periodicals, Inc.
    Relation: Journal of Applied Polymer Science 111:2099-2103
    Appears in Collections:[生物科技學系] 期刊論文

    Files in This Item:

    File Description SizeFormat
    0KbUnknown760View/Open
    310904400-8632 .doc48KbMicrosoft Word536View/Open


    All items in ASIAIR are protected by copyright, with all rights reserved.

    DSpace Software Copyright © 2002-2004  MIT &  Hewlett-Packard  /   Enhanced by   NTU Library IR team Copyright ©   - Feedback