Mahmood, Samsul Arfin2020-02-262020-02-262019-12https://hdl.handle.net/11299/211701University of Minnesota M.S.M.E. thesis. December 2019. Major: Mechanical Engineering. Advisor: Venkata Menta. 1 computer file (PDF); viii, 60 pages + 2 supplementary files.With the expected exponential growth prospects of additive manufacturing, petroleum-based plastic products and applications are also expected to increase. Since last two decades, plastic pollution has become a concerning fact. About 25 million tons of plastics find their way into the environment annually. Traditional plastics are not biodegradable and hence they end up in landfills which is detrimental for the environment. Hence, there exists a need for renewable alternatives to traditional petroleum-derived plastics. Lignin, an abundant plant-derived feedstock, has been a perfect candidate for renewable materials. The work in this thesis focuses on investigating the effects of mixing lignin extracted from tobacco with high-density polyethylene (HDPE) in varying concentrations. This work is performed in three stages. The first stage is the making blends of HDPE-lignin at varying concentrations (5, 10, 15 & 30 wt.%). Later all the materials were melt mixed using a single screw extruder. In the later stage for mechanical testing purposes, tensile specimens were processed via injection molding. During this process effect of lignin in injection molding parameters were investigated. In the second stage, mechanical, physical and thermal tests were conducted to analyze the effects of blending on the performance of the resulting products. Tensile tests were performed to evaluate the ultimate tensile strength (UTS), Young’s modulus and elongation at break for each blend composition. To evaluate the physical properties, hardness and density of the blends were measured. The miscibility of the blends was studied using optical microscopy. TGA tests were performed to study the thermal stability of blend materials. In the third stage, maleic anhydride grafted polyethylene was used to compatibilize blend materials. Compatibilized HDPE-Lignin blend materials were later subjected to mechanical and physical tests to analyze and compare the effect of compatibilizer.enBiodegradabilityLigninPolyethylene Lignin blendsTobacco ligninThesis or Dissertation