Internal mobility of PMMA in concentrated CDCl3 solutions, 1. 1H NMR spectra

Abstract

AbstractMeasurements of the second moment and analysis of the derivative shape of 1H NMR spectra of PMMA have shown that in CDCl3 solutions containing 60% (w/w) or more of polymer, the internal mobility of PMMA is similar to the mobility of the pure polymer. The main chain is rigid on the NMR scale, and only CH3 groups are mobile. The motion of CH2 groups, representing the segmental mobility of the backbone chain, becomes appreciable on the NMR scale at concentreations of 60–50%, depending on the temperature. Measurements of 1H MAR‐NMR spectra of solutions containing 30% or more of polymer indicate spatial anisotropy of internal motions of PMMA. This spatial anisotropy is probably due to intermolecular interactions of ester groups, similarly as in the gels of the PMMA stereocomplex.