The radical propagation rate coefficients, k p , of methyl acrylate (MA) and 2-ethylhexyl acrylate (EHA) have been determined in bulk via high frequency (500 Hz) pulsed laser polymerization coupled to size exclusion chromatography (PLP-SEC) up to elevated temperatures (20 e T/°C e 80). Prior to the analysis of the generated polymeric material, an investigation into the branching behavior of the generated polymers has been undertaken, employing the concept of local dispersity, D(V e ). In addition, the Mark-Houwkink-Kuhn-Sakurada parameters for both poly(MA) and polyEHA were determined at each studied reaction temperature. The temperature averaged values read (K = 10.2 Â 10 -5 dL g -1 ; R = 0.741) and (K=9.85 Â 10 -5 dL g -1 ; R = 0.719) for poly(MA) and polyEHA, respectively. The local dispersity data indicate that branching in polyEHA may be considerably more prevalent than in poly(MA), as with increasing temperature polymer microinhomogeneities are observed. Consequently, the Arrhenius parameters for k p of EHA are beset with a larger error than those of MA. The activation parameters in the temperature range between 20 and 80 °Cread:E A MA = 18.5 (þ0.8 to -0.9) kJ 3 mol -1 and A MA =2.5 (þ1.2 to -0.6) Â 10 7 L 3 mol -1 3 s -1 ; E A EHA =15.8 (þ1.6 to -1.4) kJ 3 mol -1 and A EHA =9.1 (þ10.1 to -2.9) Â 10 6 L 3 mol -1 3 s -1 .
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.