The Effects of Abstractable Hydrogen in Radical Photopolymerization of Maleate/Vinyl Ether Monomers Studied with EPR and Photo-RTIR
2010 (English)In: Journal of Polymer Science Part A: Polymer Chemistry, ISSN 0887-624X, E-ISSN 1099-0518, Vol. 48, no 13, 2810-2816 p.Article in journal (Refereed) Published
In this contribution, the influence of abstractable hydrogen on the kinetics of photopolymerized vinyl ether/maleate monomer formulations is reported. The effects of chain transfer on the polymerization rate were studied with photo real-time Infra Red (IR) for formulations composed of equimolar amounts of diethyl (DEMA) and three different vinyl ethers; methyl hexyl vinyl ether where the abstractable hydrogens adjacent to the vinyl functionality have been replaced with methyl groups, ethyl hexyl vinyl ether (EHVE) which has two easily abstractable alpha-hydrogens and triethylene glycol methyl vinyl ether (TEGMVE), which has several abstractable hydrogens. Four conclusions are drawn from these studies: (i) the vinyl ether/maleate kinetics differs significantly from the classical expression R-p = KI0.5, with recorded exponential factors of 0.84 +/- 0.04 in the absence of easily abstractable hydrogens; (ii) the presence of abstractable hydrogens significantly changes the kinetics of vinyl ether/maleate polymerizations with recorded exponential factors of 0.55 +/- 0.04 for EHVE/DEMA and 0.70 +/- 0.04 for TEGMVE/DEMA; (iii) the presence of easily abstractable hydrogens leads to a preferential consumption of maleates; and (iv) electron paramagnetic resonance studies show that vinyloxy-like radicals constitute the majority of the radicals in the systems with easily abstractable hydrogens.
Place, publisher, year, edition, pages
2010. Vol. 48, no 13, 2810-2816 p.
copolymerization, ESR/EPR, kinetics (polym.), maleate, vinyl ether
IdentifiersURN: urn:nbn:se:kth:diva-25393DOI: 10.1002/pola.24050ISI: 000279251300009ScopusID: 2-s2.0-77953106954OAI: oai:DiVA.org:kth-25393DiVA: diva2:357735
QC 20101019. Uppdaterad från manuskript till artikel (20101019).2010-10-192010-10-192010-12-17Bibliographically approved