Green Antibacterial Nanocomposites from Poly(lactide)/Poly(butylene adipate-co-terephthalate)/Nanocrystal Cellulose–Silver Nanohybrids

Silver nanoparticles (AgNPs) with a diameter of 3–6 nm were uniformly reacted onto the surface of nanocrystal cellulose (NCC) via complexation leading to NCC–Ag nanohybrids with an AgNP content of 8 wt %. Subsequently, antibacterial green nanocomposites containing renewable and biodegradable poly­(lactide) (PLA), poly­(butylene adipate-co-terephthalate) (PBAT) and NCC–Ag nanohybrids were synthesized and investigated. The PBAT as flexibilizer improved the toughness of the PLA matrix while the uniformly dispersed NCC–Ag nanohybrids enhanced the compatibility, thermal stability, crystallization, and antibacterial properties of the PLA/PBAT blends. The crystallization rate and the storage modulus (E′) of the green nanocomposites were increased obviously with increasing content of CNC–Ag nanohybrids. Meanwhile, notably the antibacterial activity of the PLA/PBAT/NCC–Ag nanocomposites was achieved against both Gram-negative Escherichia coli and Gram-positive Staphylococcus aureus cells. The antibacterial performance was mainly related to the antibacterial nature of the finely dispersed NCC–Ag nanohybrids. The study demonstrates great potential of the green nanocomposites in functional packaging and antibacterial textile applications.