RESUMEN
Polylactic acid (PLA) is a biodegradable and biocompatible polymer with versatile applications in packaging and medicine. It is derived from lactic acid and thus represents an eco-friendly option sourced from renewable raw materials. Despite its advantages, PLA exhibits few drawbacks, such as brittleness and relatively high melting and glass transition temperatures. However, these limitations can be addressed through copolymerization with other monomers like ε-caprolactone (ε-CL), resulting in a composite material with improved physical properties. This paper comprehensively reviews achievements in PLA-PCL copolymerization using organometallic catalysts, discussing scientific findings and various copolymer architectures obtained, including random or block configurations. It also demonstrates various sustainable catalysts for achieving the required microstructure under mild reaction conditions without the aid of any external initiator.
RESUMEN
Unprecedented ring-opening polymerization of quinazolinones to produce novel polyacylamidines, led by a unique cooperation between a cesium metal center and imino-phosphanamidinate ligand, was developed. Morphological studies revealed the formation of a unique macromolecular assembly producing nanofibers in the absence of a templating agent with excellent control of molecular weights and polydispersity index.
RESUMEN
A cesium imino-phosphanamidinate, [{NHIDippP(Ph)NDipp}Cs], enabling efficient ring-opening (co)polymerization of rac-LA and ε-CL is disclosed. Owing to the highly controlled polymerization, precise di-block copolymers (PLA-b-PCL) with different block lengths can be produced by a simple one-pot reaction. NMR, GPC, DSC and microscopic analyses confirm the production of di-block copolymers with crystalline properties.