Grant: Discovery Grants Program - Individual

Oil-water emulsions and composites are used extensively in cosmetics and food packaging industries. Due to the extensive use of environmentally unfriendly fossil fuel-based polymers and surfactants in these products, the incentives for identifying environmentally benign alternatives are high. Among natural-based polymers, lignin is an appealing, sustainable material due to its antioxidant, antimicrobial, and high thermal stability. Lignin is one of the most abundant renewable and biodegradable natural resources and is a by-product of the pulping industry. With the commercialization of lignin extraction technologies, e.g., LignoBoostTM, LignoForceTM, the potential application of lignin in the large-scale fabrication of marketable advanced materials has been legitimized. With this prospect in mind, research has intensified on using lignin in several applications, such as emulsions and composites. Despite previous efforts, lignin's utilization in emulsions and composites has faced challenges due to its molecular and structural heterogeneity. To tackle this problem, the use of lignin nanoparticles (LNP) for these applications has been suggested. As the science and technology for the fabrication and use of LNP are immature, the formation of functional LNP with different characteristics will be studied for the first time in this research program. This research will chemically modify kraft lignin via grafting, polymerization, and oxidation routes to bear altered charge densities, charged groups, and molecular weights. The high water solubility of these lignin derivatives will create a unique opportunity to develop an aqueous-based LNP formation system. This research program will focus on generating and characterizing LNP with different characteristics, such as surface charges and charged groups, particle size, softness, and hairy surface structure. Subsequently, using LNP in emulsions and composites will be studied comprehensively. Scientifically, the PhD (and undergraduate) students involved in this program will identify the correlations among lignin derivatives, LNP, and emulsion/composite characteristics. The outcomes of these studies will be identifying conditions for generating LNP-containing emulsion and composite systems with the best performance. The MSc students will utilize this knowledge and conduct systematic studies to develop technologies for fabricating LNP-containing emulsions and composites in one-pot systems. Then, they will use the generated data to investigate the techno-economic feasibility of the developed processes. This program helps the pulping industry identify a pathway for utilizing its lignin and creating a route for fabricating environmentally friendly and sustainable emulsion and composite systems. Another benefit of this program is training high-quality personnel with expertise in material science, biorefining, and nanotechnology, with tremendous job opportunities in Canada and elsewhere.