Investigation of microstructure in poly(methyl methacrylate) prepared via ambient temperature ARGET-ATRP: a combined approach of 1D and 2D NMR spectroscopy

This investigation reports the analysis of different microstructures present in poly(methyl methacrylate) (PMMA) using1D and 2D NMR spectroscopy. The PMMA used in this study has been prepared via activators regenerated by electron transfer atom transfer radical polymerization (ARGET-ATRP) in DMF at ambient temperature using methyl 2-chloro propionate (MCP) as initiator, CuBr2 as catalyst in combination with N, N, N´, N´´, N´´- pentamethyldiethylenetriamine (PMDETA) as ligand and ascorbic acid as reducing agent.13C NMR, which provides good information about tacticity of a polymer, has been used extensively along with 1H NMR spectroscopy to extract the information about the different microstructures present in PMMA. Heteronuclear multiple-bond correlation (HMBC), heteronuclear single-quantum coherence (HSQC), and total correlation spectroscopy (TOCSY) were also used to study the position of protons, couplings with carbon etc. in the PMMA.