Free Energy Change Of Crystallisation In Single Copolymers

We performed dynamic Monte Carlo simulations to calculate the free energy change of crystallisation in single linear and ring polymers containing one or more non-crystallisable sequence defects (comonomers) along the chain. We found that, similar to chain ends, the numbers of comonomers bring only a thermodynamic effect to the free energy barrier and shift down the melting points of single copolymers by following Flory's thermodynamic equation. Furthermore, there exists a critical comonomer number (or sequence length) for the success of crystallisation, which explains the segregation of sequence lengths upon crystallisation in statistical copolymers. Our observations shed light onto the kinetic suppression of crystallinity for polymers containing various chemical, geometrical or stereo-optical sequence defects, as well as for protein molecules containing specific sequences.[GRAPHICS].