Thiol-ene coupling of 1,2-disubstituted alkene monomers: The kinetic effect of cis/trans-isomer structures
2010 (English)In: European Polymer Journal, ISSN 0014-3057, E-ISSN 1873-1945, Vol. 46, no 12, 2321-2332 p.Article in journal (Refereed) Published
The free-radical induced reaction between a tri-functional thiol (2-ethyl-(hydroxymethyl)-1,3-propanediol trimercapto propionate) and two 1,2-disubstituted alkenes (methyl oleate and methyl elaidate) has been investigated under photochemical conditions. The photoreaction was monitored via time-resolved FUR, Raman and NMR spectroscopy to provide insights about the kinetics and efficiency in end-product formation. The information collected was subjected to numerical modelling using the GEPASI software using pre-established literature values for the rate coefficients in order to verify the proposed reaction scheme. The results confirm the thiol-ene reaction mechanism showing a very fast cis/trans-isomerization (<1.0 min) when compared with the total disappearance of unsaturations, indicating that the rate-limiting step controlling the reaction is the hydrogen transfer from the thiol involved in the formation of product. High thiol-ene conversions can be obtained at reasonable rates without major influence of side-reactions when performed in bulk indicating that this reaction is suitable for network forming purposes with mono-unsaturated fatty acid methyl esters derivatives. The kinetic and mechanistic information collected provides a basis for the design of new thiol-ene systems aiming at material and coating applications.
Place, publisher, year, edition, pages
2010. Vol. 46, no 12, 2321-2332 p.
Thiol-ene chemistry, Real-time FTIR, Photopolymerization, Fatty acids, Isomer/isomerization, Coatings
IdentifiersURN: urn:nbn:se:kth:diva-28194DOI: 10.1016/j.eurpolymj.2010.10.001ISI: 000285128700013ScopusID: 2-s2.0-79954618129OAI: oai:DiVA.org:kth-28194DiVA: diva2:384713
FunderSwedish Research Council, 621-2007-5723
QC 201101102011-01-102011-01-102013-10-02Bibliographically approved