Monte Carlo/reference interaction site model

Between the appearance of the MD studies by Vishnyakov and Neimark [56], and that by Urata et al. [60], Khalatur, Khokhlov and co-workers published two coarse-grained molecular modelling studies of Nafion [64, 65] that utilised rather different approaches to studying the morphology of PFSIs. The first of these [64] was based on a hybrid Monte Carlo/reference interaction site model (MC/RISM). The principle behind this method was to use MC simulations, based on the rotational isomeric state (RIS)... 

The older mean-field theories are often based on the lattice model of ill-defined a priori size and shape, neglecting variability of monomer structures in PO copolymers and blends. Several newer approaches have been proposed, viz., the polymer reference interaction site model (PRISM) (Schweizer and Curro 1989, 1997), the Monte Carlo (MC) simulations (Sariban and Binder 1987 Muller and Binder 1995 Weinhold et al. 1995 Escobedo and de Pablo 1999), the continuum field theory (CFT) (Fredrickson et al. 1994), or an analytical lattice models (Dudowicz and Freed 1991). The latter model leads to relatively simple mathematical expressions, which offer an insight into basic thermodynamics, but again do not predict how monomer structure affects blend miscibility. 

We also note that the same Monte Carlo data have helped to sort out an inadequate approximation in the context of the polymer reference interaction site model (PRISM) theory, which yielded a relation Tc oc /N while now oc is generally accepted. It has been very difficult to provide convincing experimental evidence on this issue— true symmetrical monodisperse polymer mixtures hardly exist, and the temperature range over which Tc N) can be studied is limited by the glass transifion temperature from below and by chemical instability of the chains from... 

---