ABSTRACT
Growing concerns in addressing environmental challenges are driving the rapid advancement of both bio-based and environmental friendly materials. Biodegradable polymers have been compounded with various nanofillers to fulfill the multiple requirements in real applications. However, current technologies remain to be improved in terms of the intrinsic inferior performance and the lack of interfacial interactions. In this work, we employed a facile route to develop bio-nanocomposites integrating multiple functionalities by reactive processing of polylactide and reactive boehmite nanorods. The grafting of polymer chains onto the surface of the nanorods encourages fully homogeneous dispersion of nanofillers with even 30 wt% loadings. Such nanocomposites exhibit simultaneously enhanced tensile strength, modulus, ductility, and impact strength. Moreover, the bio-based nanocomposites present promising features such as high transparency, improved flame resistance, and heat resistance. This work demonstrates exciting opportunities to produce bio-plastics with diverse functionalities in versatile applications of sustainable packaging industry and engineering plastics.
ABSTRACT
The interfacial nanoparticle compatibilization (INC) strategy has opened up a promising avenue toward simultaneous functionalization and interfacial engineering of immiscible polymer blends. While the INC mechanism has been well developed recently, few investigations have focused on rigid nanoplatelets because of the inherent steric hindrance of the surface-grafted polymer chains. Herein, surface-modified rigid nanoplatelets have been incorporated into an immiscible poly(l-lactide) (PLLA)/poly(butylene succinate) (PBSU) blend. It is demonstrated that the strong interfacial adhesion between PLLA and PBSU phases is promoted via molecular entanglements of the grafted chains on the surface of nanoplatelets with the individual components. A refined phase morphology with improved mechanical properties can be achieved with the addition of 5 wt % modified Gibbsite nanoplatelets. It was further found that the stiffness of nanoplatelets can change the geometry of the interface significantly. It is, therefore, indicated that the simultaneous interface strengthening and interfacial curvature controlling of rigid nanoplatelets originate from the selective swelling/collapse of the in situ-formed PLLA and PBSU grafts within the corresponding phase at the interface. Such a mechanism is confirmed by the Monte Carlo simulations. This work provides new opportunities for the fabrication of advanced polymer blend nanocomposites.
