The Influence of Ultraviolet Irradiation on the Structure and Properties of Acrylonitrile Butadiene Styrene/Lignin Composites

ABS plastic is an inexpensive material with attractive physical and chemical properties. Unfortunately, it is susceptible to degradation under UV radiation, so it limits the use of this material outdoors. In this paper, we demonstrate a low-cost approach to reduce the photodegradation of ABS plastic by using additives of kraft lignin and dioxane lignin as UV absorbers. Lignin is an abundant plant polymer, which is a waste product of the pulp and paper industry. Non-regular structure of lignin hampers its use in industry. However, there is possible use of lignin as an addition to enhance the properties of resulting materials. In this study, we obtained composites of ABS and lignin with the hot extrusion method. Adding up to 15% of lignin to ABS plastic does not have a significant negative impact on tensile properties. We irradiated the resulting composites with UV and studied the UV effects on their mechanical properties and chemical structure. Oxidative degradation was characterized by FTIR and 2D NMR methods. The results showed that small lignin additions reduced the photodegradation of ABS. The previously undescribed product of the degradation of the obtained composites was detected with the use of the set of 2D NMR spectra of the composites. We proposed a scheme for the formation of this photodegradation product based on the obtained data.