Molecular mechanics investigation of some acrylic polymers using SPASIBA force field

Abstract

The First generation SPASIBA force field is used to study normal vibrational modes of PMMA, and then extended to other thermoplastic polymers, namely PMA, PMAA and PAA, in order to determine its param- eters transferability. To this end, FTIR and FTR spectra of pure PMMA samples, prepared by the emulsion polymerization of MMA and initiated by sodium, are recorded in 400–3500 cm−1,respectively. A detailed vibrational analysis was performed on the obtained spectra and the observed frequencies are assigned to their respective vibrational modes, supported by potential energy distribution (PED) analysis. Our numerical results reveal an RMS value of 7.8 cm−1 corresponding to IR wavenumbers and 8.7 cm−1 relatively to Raman wavenumbers. Our vibrational calculations on PMA, PMAA and PAA polymers reveal that the parameters transferability criterion, established by Shimanouchi, is verified for the SPASIBAforcefield. and 200–3500 cm−1