ИСТИНА

A framework for multi-scale simulation of polylactic acid (PLA) and its oligomers (OLA) has been developed and employed for investigation of local ordering and segregation in PLA/OLA blends. The framework comprises the A-graft-B coarse-grained model, with the atoms of the PLA backbone represented by A units forming the coarse-grained backbone and the methylene groups represented by B side pendants. The force-field of the coarse-grained model was derived based on a phase trajectory of atomistic simulations of OLA melt. The force-field correction law for temperature transferability was derived to ensure close resemblance of melt density and spatial properties of the chains in coarse-grained and atomistic representations. The coarse-grained model was complemented with a reverse mapping procedure which reconstructs the atomistic structure of the chains based on positions of coarse-grained beads. The testing has shown that the properties of the melt samples created and equilibrated in the framework of the coarse-grained model and then converted to an all-atom representation are identical to those initially simulated in all-atom approach.