“…The molecular motions can usually be calculated by means of dielectric relaxation, nuclear magnetic resonance (NMR) spectroscopy, dynamic mechanical analysis (DMA), differential scanning calorimetry (DSC) etc. [3][4][5][6] In addition to these measurements, theoretical calculations and computer simulations may be used to assist in the identification of the possible molecular motions. [7 -20] Boyd et al, [7][8][9] for example, have investigated the glass transition temperatures of polyethylene, polyisobutylene, etc., by MD simulations, and Sung et al [10,11] have explored the rotations of phenylene rings and segmental motions.…”