On the short time dynamics of dense polymeric systems and the origin of the glass transition: A model system

In order to model the short time (and distance) scale motions for dense polymeric systems, we have performed dynamic Monte Carlo simulations of chains on a diamond lattice at considerably greater densities than those done previously. Chain dynamics were simulated by a random sequence of three‐ and four‐bond kink motions and end moves. For times shorter than the chain diffusion time, the single bead autocorrelation function g(t) exhibits three distinct regimes: a short time Rouse‐like regime where g(t)∼t1/2; a mid‐region where g(t)∼t β, followed by a longer time, Rouse‐like regime where g(t)∼t1/2. There is a smooth crossover from Rouse‐like dynamics, β=1/2, at low density to smaller values of β at higher density, and β=0 at the glass transition density (φG =0.92±0.01). It is shown that the major motion of the chains is transverse to the chain contour rather than along the chain. The observed motion is successfully analyzed in terms of the motion of defects (holes) through the sample. It is shown that the g...

[1]  P. Flory,et al.  Second‐Order Transition Temperatures and Related Properties of Polystyrene. I. Influence of Molecular Weight , 1950 .

[2]  P. E. Rouse A Theory of the Linear Viscoelastic Properties of Dilute Solutions of Coiling Polymers , 1953 .

[3]  M. Fisher,et al.  On random walks with restricted reversals , 1958, Mathematical Proceedings of the Cambridge Philosophical Society.

[4]  J. Ferry Viscoelastic properties of polymers , 1961 .

[5]  P. Gans Self‐Avoiding Random Walks. I. Simple Properties of Intermediate‐Length Walks , 1965 .

[6]  Peter H. Verdier Monte Carlo studies of lattice‐model polymer chains. III. Relaxation of Rouse coordinates , 1973 .

[7]  R. E. Robertson,et al.  The Physics of Glassy Polymers , 1973 .

[8]  F. T. Wall,et al.  Macromolecular dimensions obtained by an efficient Monte Carlo method without sample attrition , 1975 .

[9]  Hiroshi Okamoto,et al.  Monte Carlo study of systems of linear oligomers in two‐dimensional spaces , 1976 .

[10]  J. Curro Monte-Carlo Simulation of Multiple Chain Systems. Second and Fourth Moments , 1979 .

[11]  Gary S. Grest,et al.  Liquid-glass transition, a free-volume approach , 1979 .

[12]  B. Briscoe,et al.  The diffusion of long-chain molecules through bulk polyethelene , 1979, Proceedings of the Royal Society of London. A. Mathematical and Physical Sciences.

[13]  Kenneth E. Evans,et al.  Computer simulation of the dynamics of highly entangled polymers. Part 1.—Equilibrium dynamics , 1981 .

[14]  M. Ratner,et al.  Dynamic bond percolation theory: A microscopic model for diffusion in dynamically disordered systems. I. Definition and one‐dimensional case , 1983 .

[15]  Kurt Kremer,et al.  Statics and dynamics of polymeric melts: a numerical analysis , 1983 .

[16]  Jean-Louis Viovy,et al.  Dynamic Monte Carlo simulations of dense polymer systems on the tetrahedral lattice: A liquid‐glass‐type transition , 1984 .

[17]  Artur Baumgärtner,et al.  SIMULATION OF POLYMER MOTION , 1984 .

[18]  R. Palmer,et al.  Models of hierarchically constrained dynamics for glassy relaxation , 1984 .

[19]  Glenn H. Fredrickson,et al.  Kinetic Ising model of the glass transition , 1984 .

[20]  J. Kovac,et al.  Dynamics of cubic lattice models of polymer chains at high concentrations , 1985 .