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Significant progress has been made recently in the field of atomistic simulation of polymer melts through the advent of new powerful Monte Carlo methods. This article reviews the state of the art in the area. Sampling the configurational space of a dense polymer system is difficult, because of complications introduced by high density and the connectivity of the chain molecules. W e describe how some novel algorithms attempt to solve the problem, compare them using a set of stringent performance criteria and discuss their strengths and their weaknesses, their successes and their failures. Although we have still not reached the stage where realistically long polymeric chains with atomistic detail can be treated successfuJly, there is ground for hope. Configurationbias Monte Carlo (CBMC) and its extensions, concerted-rotation (ConRot)-based algorithms, and hybrid Monte Carlo (HMC) have opened up new possibilities for the investigation of more realistic polymer models than the ones used hitherto. The field of possible applications is vast: studies of polymers in melts and in solution, prediction of single-phase thermodynamic properties and phase equilibria, biopolymer modelling and, hopefully, the long-time behaviour of macromolecular systems, may soon become tractable with the rapid evolution of novel Monte Carlo methods.

The global orientational order that develops in polycarbonate under plastic deformation has been measured quantitatively by CSA and dipolar DECODER experiments. The results are in substantial agreement with the predictions of an affine entanglement network model. Athermal atomistic simulations, on the other hand, tend to overestimate the orientational order. The orientation behavior in glassy polycarbonate seems to be essentially the same as that in the melt.

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From the comparison of experimental low-pressure pVT data for a short alkane with the results of Monte Carlo simulations in the NpT ensemble of an atomistically detailed model of polymethylene (PM) with explicit hydrogens, we have obtained Lennard-Jones parameters that allow accurate prediction of pVT behavior for liquid long-chain alkanes at high pressure. The parameters were obtained from the Slater–Kirkwood formula and fitted to the experimental density of n-pentane at 0.1 MPa; they faithfully reproduce experimental data for chains up to C23H48 (n-tricosane) and pressures up to 100 MPa over a wide temperature interval.