Effect of Lignin Incorporation and Reactive Compatibilization on the Morphological, Rheological, and Mechanical Properties of ABS Resin

In order to develop the potential application of industrial alkali lignin, its acrylonitrile-butadiene-styrene (ABS) composites were fabricated via melt blending in the absence/presence of a compatibilizer. The lignin can uniformly disperse in the ABS matrix with number-average dispersed-phase domains of sub-micron scale, ranging from 150–250 nm, as observed by scanning electron microscopy. Infrared spectroscopy reveals that strong intermolecular interactions, mainly hydrogen bonding, were responsible for their good interfacial compatibility. Rheological behaviors show that the presence of lignin restricts to some extent the relaxation of polymer chains without affecting the processing properties of ABS resin. The presence of lignin increases storage modulus and glass transition temperature (T g) of ABS. Incorporating small amounts of lignin, e.g. 5 wt%, can produce ABS composites with enhanced tensile strength and modulus, while higher loading of lignin will reduce mechanical properties. The latter, however, can be improved by reactive compatibilization.