(a)
(b)
Figure 3: (a) FTIR spectrum of an RMGI sample in the range of 1800–1500 cm−1: the peak at ~1724 cm−1 indicates the ester bond (C=O str), the peak at ~1637 cm−1 indicates the methacrylate C=C bond (C=C str), and the peak at ~1562 cm−1 indicates the carboxylate salt formed (C=O str of COOM). (b) Deconvolution of the complex ester peak into three subpeaks: unionized carboxyl groups at ~1732 cm−1, ~1724 cm−1 and ester groups dependent on substitution at ~1708 cm−1.