Smart Design of Rapid Crystallizing and Nonleaching Antibacterial Poly(lactide) Nanocomposites by Sustainable Aminolysis Grafting and in Situ Interfacial Stereocomplexation

Sustainable antibacterial poly(lactide) (PLA) nanocomposites have attracted plenty of attention due to their potential application in biomedical and packaging fields. However, the preparation of nonleaching antibacterial PLA nanocomposites with high crystallinity is still a challenge due to their poor compatibility and the low crystallization rate of PLA. An effective and facile way by compounding poly(d-lactide) (PDLA) with poly(l-lactide) (PLLA)-grafted ZnO that was synthesized via in situ aminolysis reaction at the surface of ZnO was designed to simultaneously overcome these limitations. During solution mixing, the PDLA matrix and the grafted PLLA chains tend to orient side by side at the PDLA/ZnO interface and finally cocrystallize into stereocomplex (sc) crystallites. The interfacial stereocomplexation not only serves as a nucleator to increase the crystallization rate of the matrix but also effectively prevents ZnO from leaching out of the polymer matrix. Meanwhile, the nanocomposites have excellent biocompatibility. Therefore, it may provide an effective route to prepare advanced PLA-based materials with a fast crystallization rate, excellent biocompatibility, and nonleaching antibacterial property in this work, thus broadening the application range of PLA in biomedical applications.