%0 Journal Article
%T Nitroxide-Mediated Photo-Controlled/Living Radical  Polymerization of Methacrylic Acid
%A Eri Yoshida
%J Open Journal of Polymer Chemistry
%P 16-22
%@ 2165-6711
%D 2013
%I Scientific Research Publishing
%R 10.4236/ojpchem.2013.31004
%X <p style=\"text-align:justify;\" class=\"MsoNormal\">
	<span lang=\"EN-US\">The photo-controlled/living radical polymerization of methacrylic acid (MAA) was performed at room temperature by irradiation with a high-pressure mercury lamp using azo</span><span lang=\"EN-US\"> </span><span lang=\"EN-US\">initiators and 4-methoxy-2,2,6,6-tetramethylpiperidine-1-oxyl as the mediator in the presence of (4-<i>tert</i>-butylphenyl)diphenylsulfonium triflate (<i><sup>t</sup></i>BuS) as the accelerator. Whereas the bulk polymerization yielded polymers with a bimodal molecular weight distribution in both the absence and presence of <i><sup>t</sup></i>BuS, the solution polymerization in methanol produced unimodal polymers with the molecular weight distribution of 2.0</span><span lang=\"EN-US\"> </span><span lang=\"EN-US\">-</span><span lang=\"EN-US\"> </span><!--?xml:namespace prefix = st1 /--><st1:chmetcnv w:st=\"on\" unitname=\"in\" sourcevalue=\"2.3\" hasspace=\"True\" negative=\"False\" numbertype=\"1\" tcsc=\"0\"><span lang=\"EN-US\">2.3 in</span></st1:chmetcnv><span lang=\"EN-US\"> the presence of <i><sup>t</sup></i>BuS. The molecular weight distribution of the resulting poly</span><span lang=\"EN-US\"> </span><span lang=\"EN-US\">(MAA) decreased with an in</span><span lang=\"EN-US\">- </span><span lang=\"EN-US\">crease in <i><sup>t</sup></i>BuS. The dilution of the monomer concentration also reduced the molecular weight distribution. The use of the initiator with a low 10-h half-life temperature also effectively controlled the molecular weight. The livingness of the polymerization was confirmed by obtaining linear increases in the first-order conversion versus time, the molecular weight versus the conversion, and the molecular weight versus the reciprocal of the initiator concentration.</span><span lang=\"EN-US\"><!--?xml:namespace prefix = o /--><o:p></o:p></span> 
</p>
%K Photo-Controlled/Living Radical Polymerization
%K Nitroxide-Mediated Polymerization
%K Methacrylic Acid
%K 4-Methoxy-2
%K 2
%K 6
%K 6-Tetramethylpiperidine-1-Oxyl
%K (4-Tert-butylphenyl)diphenylsulfonium Triflate
%K Molecular Weight Control
%U http://www.scirp.org/journal/PaperInformation.aspx?PaperID=28474