The free radical copolymerization characteristics of α-methylene γ-butyrolactone

An Investigation of Free Radical Copolymerization Kinetics of the Bio‐renewable Monomer γ‐Methyl‐α‐methylene‐γ‐butyrolactone with Methyl methacrylate and Styrene

“…These values of the monomer reactivity ratios are compared to published values for a-MBL/MMA, [8] a-MBL/ST [8,11] and MMBL/ST copolymer [17] in Table 1 ST/a-MBL [6] 0.09 0.70…”

“…[6][7][8][10][11][12] The a-MBL homopolymer was found to have a significantly higher glass transition temperature than pMMA (T g of 195 vs. 105 8C), and the related MeMBL monomer produced a polymer with an even higher T g of 210-220 8C. [6,7,11] Polymer specimens moulded above these temperatures were clear, hard and brittle with improved solvent resistance.…”

“…[9] This process avoids the costly and time-consuming methods used previously [15,16] and generates a bio-renewable monomer. [9] Kinetic data for gamma lactone copolymers are limited in the open literature, with research primarily focussed on copolymers of a-MBL and more recently MMBL with ST. [8,11,17] In order to be able to produce copolymers of MeMBL with well defined characteristics and tailored physical properties, an improved understanding of its free radical polymerization kinetics is required. As far as we know, the copolymerization propagation kinetics of MeMBL with both MMA and ST has not yet been studied using pulsed laser polymerization (PLP) techniques, and only Qi et al have examined the copolymerization of MeMBL and ST at 70 8C.…”

Nonlinear regression by visualization of the sum of residual space applied to the integrated copolymerization equation with errors in all variables. II. Application to the system methyl methacrylate-?-methylene-?-butyrolactone using on-line Raman spectroscopy

“…Using data from Akkapeddi 28 (r MBL ϭ 1.6; r MMA ϭ 0.6 at 60°C) leads to initial monomer fractions of fЈ MBL ϭ 0.55 and f Љ MBL ϭ 0.23. The copolymer composition was calculated using 1 H-NMR signals of the methoxy peaks from MBL (A OOCH 2 O , ␦ ϭ 4.3 ppm) and MMA (A OCH 3 O , ␦ ϭ 3.6 ppm) using the following relationship:…”

“…Figure 3 also shows the recalculated reactivity ratios and 95% confidence intervals of Akkapeddi. 28 It can be seen that using NLLS, different estimates were obtained as compared to using the Fineman-Ross (F-R) method:…”