RHEOLOGY AND PIPELINE FLOW BEHAVIOUR OF NANOPARTICLE-STABILIZED PICKERING EMULSIONS: MODELLING AND EXPERIMENTS

点击翻译按钮获取中文摘要

Recent research into the use of nanoparticles as emulsifiers in Pickering emulsions shows great promise for the production of new food, cosmetic and pharmaceutical products, to name a few. However, the way these Pickering emulsions behave in large-scale production systems is unknown. This research proposes to provide the models needed to predict their behavior, so that manufacturers can design plants and processes accordingly. This research will help Canadian industry capitalize on the advantages of these emulsions to produce enhanced products and so successfully compete in global markets. Many products incorporate emulsions that use surfactants to suspend one liquid in another immiscible liquid (e.g. oil and water). The surfactants stabilize emulsion products through manufacturing, packaging, transportation and storage, and help ensure they remain safe after purchase. Unfortunately, surfactants are commonly obtained from non-renewable sources and can cause health problems, including skin irritation and red blood cell damage. This is problematic in cosmetics and pharmaceuticals produced as creams, liniments and ointments for the skin. In the past decade, scientists began using solid nanoparticles of non-toxic substances, such as proteins and starches, to create surfactant-free emulsions. Their outstanding properties make them ideal for product development, but little is known about how they flow within a mass-production system. In fact, the layer of nanoparticles at the oil-/water interface of these Pickering emulsions changes their rheological and pipeline flow behaviours. Therefore, using the models for conventional surfactant-based emulsions to manufacture Pickering emulsions would cause process and quality control problems. Manufacturers need a solid understanding of the rheology and pumping behaviour of Pickering emulsions before they can design, select and operate equipment to handle, mix, store and transport such materials through a system of pipelines. And yet, no published studies adequately describe the rheology and pipeline flow of Pickering emulsions. The longterm goal of this research is to conduct modelling and experimental studies of the rheology and pipeline flow of dilute and concentrated Pickering emulsions, which will lead to models that predict how they will behave in a mass production system. Canadian industry can use these models to design cost-effective, long-lasting and energy efficient infrastructure and processes for their innovative new products. Much of this research will be conducted by students, who will become experts in a poorly understood aspect of manufacturing that could bestow a great advantage to Canadian companies. Upon graduation, the students will possess strong experimental skills and theoretical understanding of rheology, and interfacial and transport phenomena pertaining to emulsions. This transferrable knowledge, vital throughout Canada's manufacturing and resource industries, is in high demand.