Improved performance of poly(lactic acid) nanocomposites with poly(butyl acrylate)‐modified cellulose nanowhiskers

Abstract Poly(butyl acrylate) (PBA) was grafted onto cellulose nanowhiskers (CNW) via transesterification in an ionic liquid and solution polymerization in water. Fourier‐transform infrared spectroscopy, transmission electron microscopy, thermogravimetric analysis, x‐ray photoelectron spectroscopy, and x‐ray diffraction were used to determine the structure and morphology of the PBA‐modified CNW (CNW‐g‐PBA). Poly(lactic acid) (PLA)/CNW‐g‐PBA nanocomposites were prepared by solution casting. The inclusion of CNW‐g‐PBA significantly increased the composite strength, toughness, and thermal stability. The maximum tensile strength and elongation‐at‐break values were approximately 28% and 268%, respectively, higher than those of PLA. The fracture surface showed typical ductile fracture characteristics. The glass‐transition temperature raised from 56.7 for PLA to 60.3°C for CNW‐g‐PBA (5 wt% PBA), and the crystallinity rose from 1.6% to 10.3%. These findings show that the modification of nanowhiskers increased their compatibility with, and dispersion in, PLA. These results show that a combination of surface‐functionalized CNWs and PLA provides biocomposites with a broad range of applications, for example, in packaging and biomedical products. Highlights CNW‐g‐PBA was prepared by transesterification and solution polymerization route. PLA/CNW‐g‐PBA exhibited strong and tough performance. Compatibility mechanism have been developed.