Simulations of homopolymer collapse kinetics in dilute solution

We present results for the kinetics of folding of stiff and flexible homopo lymers using a variety of simulation techniques. A Monte Carlo simulation b ased on the Metropolis algorithm is implemented on a lattice, whereas; the Langevin equation is used to simulate polymers in the continuum. Using the lattice model, we study homopolymer solution at various concentrations up t o the semi-dilute regime. The conformational changes in all simulations are initiated by quenching the system to the poor soh-ent region of the phase diagram. The flexible homopolymers undergo collapse from a Flory coil to a globule. Stiff homopolymers collapse in the continuous model forming toroid al structures, whereas the system in the lattice model remained trapped in a hairpin metastable state. The lattice simulation for the homopolymer solu tion has the added complexity of polymer aggregation. The simulation shows that aggregates grow obeying the Lifshitz-Slyozov law during the main part of the process.