Preparation of functionalized cellulose nanoparticles and their effect on the crystallization behaviors of poly(l‐lactide) based nanocomposites

Abstract

AbstractA rather low crystallization rate has greatly limited the application of poly(l‐lactide) (PLLA) in many fields. Thus, functionalized cellulose nanoparticles (CPNs) were prepared based on cellulose aerogel through a novel and simple approach and were then applied as biobased nucleating agents to improve the crystallization rate of PLLA. First, isolated individual CPNs with a mean diameter around 37.2 nm and regular circular shape were obtained. Subsequently, PLLA based nanocomposites with various contents of CPNs were prepared by solution blending. As a result, CPNs promoted the crystallization rate of PLLA significantly. Compared with that of neat PLLA, the crystallinity (Xc) of the nanocomposites increased dramatically more than 30 times to 36.65% at a CPN loading of 0.5 wt%, and the half‐crystal time (t1/2) at 130 °C decreased by about 91%. Furthermore, due to the presence of CPNs, which provided a large number of nucleation sites in the PLLA matrix, the chain conformational and crystallization kinetics behavior of the PLLA based nanocomposites during isothermal crystallization were changed in the early stages, and based on this result a proposal for the nucleation process for CPNs in a PLLA matrix is presented. © 2018 Society of Chemical Industry