Yan, Ning (University of Toronto)

Purpose

There is a growing interest in utilizing renewable biomass materials to produce environmentally friendly products due to the concern for fossil fuel depletion and climate change. Bark, a waste stream produced in large quantities in saw mills and pulp and paper operations, is a valuable source of biomass that has found only a few low-valued usages in the industry. Over the last 6 years, we have developed extraction and conversion technologies for obtaining polyphenolic compounds from bark and to make value-added bark-based adhesives, resins, and foam products. However, depending on the wood species, a significant amount of solid residues still remain after the extraction. In order to realize the full potential of a bark biorefinery, utilization of all bark fractions, including the bark extraction residues, is necessary. The proposed NSERC Discovery application complements and extends our past work on bark biorefinery to focus on fundamental understanding of the nanofibrillation process of converting the bark extraction residues to highly promising novel bark-based lignocellulosic nanofibrils (BLNF) with a high lignin content. The specific research objectives that will be addressed by this NSERC proposal are to elucidate: 1) the role of bark microstructure and lignin on nanofibrillation processes of BLNF; 2) the effect of drying methods on structure, morphology, and surface topochemistry of BLNF; 3) the application of BLNF in thermoset and thermoplastic polymer composites as reinforcement for enhanced mechanical, thermal, and barrier performance. The mechanistic insights gained through these fundamental studies will contribute significantly to the realization of a true bark biorefinery process, by which all fractions of the bark materials are used for making valued added products. If successful, the bark-derived valued-added green chemicals and BLNF containing composites will reduce the market reliances on fossil fuel derived products and help transform Canadian forest mills into integrated biorefineries, greatly enhancing the forest sector's competitiveness in the global marketplace. HQP's trained by the project will be ideally suited to become the future leaders in the emerging bio-economy making significant contributions to Canada's long term prosperity and well-being.