For PMMA the polymer backbone remains intact after TMA insertion, due the location of the C=O moiety of the sidechain. However, an ethane molecule is released from the polymer upon insertion. This reaction is also exothermic, albeit less so than for PLA, with a reaction energy of -1.82 eV relative to the adduct. The peak corresponding to the redshifted C=O stretch disappears from the IR spectra upon insertion and two peaks, corresponding to the asymmetrical and symmetrical stretch mode of the chelating carboxyl group, appears at 1604.34 cm -1 and 1152.11 cm -1 respectively.