Effects of field on temperature-induced segregation and folding of polymerchains

Segregation of polymer chains and their conformations are studied as a func tion of temperature and field in two dimensions using a hybrid (discrete-to -continuum) simulation method. Temperature-induced segregation occurs on de creasing the temperature, i. e., from T=5 (desegregation) to T=1 (segregati on) followed by chains folding (T less than or equal to 0.5) in the absence of field. The amplitude of folding increases on reducing the temperature. While the presence of field induces orientational ordering and anisotropy i n the mass segregation of chains, it leads to desegregation as the field is increased above a characteristic value (E-c). Radius of gyration exhibits conformational crossover from extended (SAW) (high T) to collapse (low T) i n the absence of field, but anisotropy sets in its spread in the presence o f field. Variation of the radial distribution is consistent with these obse rvations. (C) 1999 American Institute of Physics. [S0021-9606(99)51512-2].