Revealing Structural and Physical Properties of Polylactide: What Simulation Can Do beyond the Experimental Methods

Bio-based semicrystalline polylactide (PLA) has a growing value as a substitute for fossil-based polyesters in technical applications and as a biocompatible material in medicine. The complexity of the behavior of PLA, determined by the presence of different stereoisomers, the role of electrostatic interactions, and its slow crystallization rate, makes computer simulations an important tool to discover new approaches to control the properties of PLA-based materials. The goal of this review is to summarize the efforts to simulate PLA materials with different levels of detail, including the quantum mechanical approach, all-atom modeling, and coarse-grained particle models. We focus on the validation of the models and the ways to cross-check the results with other simulation and experimental data. Special attention is devoted to the simulations of PLA in the presence of water, which provide insights into molecular mechanisms of hydrolytic degradation of PLA, especially at the initial stage, when the structural changes can not yet be detected by experimental methods. Ultimately, the selection of the appropriate simulation methods can facilitate material design, by combining the throughput and level of detail necessary for the job.