An alternative method to estimate the bulk backbiting rate coefficient in acrylate radical polymerizationElectronic supplementary information (ESI) available. See DOI: 10.1039/c6py01468b

Based on a pulsed laser polymerization-size exclusion chromatography (PLP-SEC) analysis, an alternative method to estimate the bulk backbiting rate coefficient k bb in acrylate radical polymerization is presented. For different solvent volume fractions (0-0.75), using the unsaturated analogue of the monomer as a solvent to rule out solvent effects, regression analysis is applied to inflection point data in the low frequency range (< ca. 100 s −1 ) only, which can be scanned with less expensive PLP equipment. Variation of the solvent volume fraction allows the independent alteration of the average mid-chain radical lifetime and improvement in the sensitivity of the method to estimate k bb confidently. The robustness of the method is verified considering in silico generated data including large artificial errors. The method is applied to experimental data of 2,2-dimethoxy-2-phenylacetophenone (DMPA) initiated PLP of n -butyl acrylate, taking butyl propionate as the solvent. A k bb value of 171 ± 21 s −1 (303 K) is found, in good agreement with literature data. The method presents a generic approach for the estimation of k bb for other acrylate monomers, allows a complete statistical analysis, and can be used as a complementary tool for existing methods. In the long term, the method can even be extended for the simultaneous estimation of the bulk k bb and mid-chain radical propagation rate coefficient k p,m . An alternative method to estimate the backbiting rate coefficient in acrylate polymerization is presented and successfully applied to experimental data.