Plastic deformation of glassy polymethylene: Computer-aided molecular-dynamic simulation

Effect of plastic deformation on the character of micro-brownian motions in glassy poly(methyl methacrylate)

“…In our opinion, this result is extremely interesting. PMMA stores excess energy during plastic deforma tion [2,3,20]. The concentration of ester groups in PMMA is high.…”

“…Ideas about the dominant role of intermolecular structural factors in the plastic deformation of glassy polymers were expressed in [2,3]. The suggested pic ture explains the experimentally observed weak sensi tivity of the kinetics of β motions to structural rear rangements during deformation.…”

“…At deformation temperature Т def (above glass tran sition temperature T g ), inelastic deformation mass transfer in polymers is mainly provided by the segmen tal α motions of chains. However, it is assumed that the α mobility is "frozen out" during low temperature deformation (at Т def ≤ 0.7T g ) and that segmental motions cannot participate in the plastic deformation of glass [1][2][3][4]. The temperature boundary of 0.7Т g was estimated on the basis of the plasticity studies of crys talline metals because, at Т def lower than or approxi mately equal to (0.5-0.7)Т m , the diffusion mechanism of plastic deformation cannot be implemented and mass transfer proceeds only via generation and sliding of dislocations [5].…”

Simulating the ultrathin layer structure of dichloromethane on a solid substrate by means of density functional theory and molecular dynamics

“…These methods can be used to parameterize the mole cule-molecule and molecules-solid surface interac tion potentials apart from logically predicting a sub stance's properties (density, glass transition tempera ture, volume expansion coefficient, diffusion, free volume, heat conductivity, and so on [11][12][13][14][15][16][17][18]). Let us clarify this in detail.…”

“…For example, atomistic modeling uses force fields obtained from quantum mechanical calculations, followed by forcing the obtained param eters to fit the experimental data [21][22][23][24]. Hence MC and MD allow us not only to analyze the molecular structure of a system containing up to 10 7 atoms but also to calculate their physical properties with a high degree of accuracy [11][12][13][14][15][16][17][18]. Statistical analysis of the intermolecular distances and the mass centers of poly meric chain fragments in turn provide a way of deter mining the pair potentials of mesoscopic particle interaction (correlating with various total combina tions of atoms and molecules) needed to use the meso scopic methods.…”