Monte Carlo Simulations Of Competitive Polymer Crystallization In Binary Blends

The nucleation-growth mechanism is the typical mode for polymer crystallization.There are two extreme nucleation modes for polymer crystallization.The first one is intramolecular nucleation with most of crystalline stems folded adjacently.The second one is intermolecular nucleation with all the crystalline stems connected with cilia.We performed dynamic Monte Carlo simulations of nucleation and growth of two crystals separately constructed by uniform-and staggered-component polymers in half-half symmetric binary blends.We observed that under separate enhancement of the driving forces for two crystallization,the molecular-uniform crystals exhibit faster nucleation and growth with larger amount of chain-folding as well as with less extent of thickening than the parallel-enhanced molecular-staggered crystals.We attributed the results to the molecular-uniform crystals preferring more intramolecular nucleation than the molecular-staggered crystals.Our simulations provide a direct molecular-level evidence to the kinetic selection of intramolecular crystal nucleation,which is responsible for chain-folded lamellar crystals upon polymer crystallization from quiescent solutions and melt.