Structure Formation of a Single Polymer Chain. I: Growth of trans Domains

"Molecular dynamics simulations are carried out to study structure formation of a single polymer chain with 500 CH_2 groups. Our simulations show that the orientationally ordered structure is formed at a low temperature both by gradual stepwise cooling and by quenching from a random configuration at a higher temperature. The growth of the global orientational order proceeds in a gradual manner in the case of gradual stepwise cooling, whereas it proceeds in a stepwise manner in the case of quenching. From the microscopic analysis of the structure formation process, we find the following characteristic features: (i) In the case of gradual stepwise cooling, the global orientational order grows gradually through the incorporation of small trans domains and the surrounding trans segments into the largest trans domain. (ii) In the case of quenching, the growth of the orientational order is either due to the incorporation of small trans domains and the surrounding trans segments into the largest trans domain or due to the elongation of the trans segments in the largest trans domain. The last feature endorses the previously proposed hypothetical grand view of self-organization [e.g. T. Sato, Phys. Plasmas 3, 2135 (1996)]: when a system is driven far from equilibrium, it will evolve to a more stable state in a stepwise fashion irrespective of its fundamental interaction forces.