Cover: Accurate chain-length dependent termination and the persistent radical effect play and important role in the accurate and predictive modelling of living radical polymerizations. This will allow new insights into mechanistic pathways to be deduced. Further details can be found in the article by G. Johnston-Hall, M. J. Monteiro^* on page 387.

Kinetic simulations using the composite k_t model allows a better understanding of the effects of the persistent radical affecting ATRP or for that matter any activation-deactivation system. It also provides a better fit to experimental data in either bulk or solution conditions for ATRP polymerizations carried out at 110°C. The PRE controls the molecular weight distribution, exemplified by a linear increase in with conversion and a low PDI.

Assuming power law dependencies of the size ρ ∼ N^ν of a chain on its length N at two different states, a scaling relationship is derived between the extending force F and the extension ρ of the chain. The exponent γ of the force/extension relation depends on both exponents ν_i and ν_f of the initial and the final states. The simplicity of the derivation permits the explanation of previous results and predicts some more.

Stochastic simulations of a diblock copolymer melt demonstrate that the Leibler-Ohta-Kawasaki phase-field model is a capable and appropriate simulation framework for examination of long-wavelength line edge roughness and line width roughness in diblock copolymer resists.

Using MD simulations, it is demonstrated that the transition from liquid-like behavior characteristic for small molecules to Rouse dynamics characteristic for polymers, in a series of polyisoprenes with molecular weights M = 70–6 802 g · mol⁻¹ is a smooth function of molecular weight. The results show that the Rouse behavior establish at molecular weights of about 1 000 g · mol⁻¹, which roughly corresponds to ≈14 monomer units in the chain.

A simple theory of the finite-extensibility effect on the equilibrium size of a single polymer chain is developed in this paper. Compared to the result from Flory's classic theory, the finite extensibility decreases the equilibrium chain size systematically. This effect is important and necessary to be taken into account for a chain with a short contour length and/or with strong repulsions between monomers. The highly charged and highly crosslinked hydrogel is a typical system where the finite extensibility plays an important role.

An RIS model for the erythro diisotactic isomer of PNB was developed that reflects the observed helix-kink morphology. MC simulations indicate that the origin of the kink is the reversal of the helical symmetry, which occurs in approximately 0.2% of the monomeric units. These kinks can form or be destroyed at the polymer ends, and each one of these kinks adds approximately 4kcal·mol⁻¹ to the energy of the helical structure. The basic format of the RIS model developed here may be applicable to other polymers as well.

A generalized Gibbs-Thomson equation is derived for one-component polymer systems with two crystalline phases. Its application to the PT phase diagram of polyethylene is demonstrated. Comparison with experimental data leads to estimates for the structural characteristics such as the ratio of the surface free energy to crystal length of the polymer crystal for the respective crystalline phases.

By Monte Carlo simulations we provide insight into the isolated single- and double-tethered polymer chain attached to an impenetrable surface to elucidate open theoretical questions and to guide future experiments investigating the impact of tethering on the packaging of the genome by concurrent visualisation of multiple loci along the chromosome(s) in eukaryotic and prokaryotic organisms.