Grant: Strategic Projects - Group

Micro/nanocellular foaming of polymers is an engineering process to create voids or bubbles of microns and nanometers in polymers. The foamed polymers can save the amount of material for products by up to 50% without compromising their properties, as compared with conventional, un-foamed polymers. The use of supercritical fluids, CO2 and N2 in this study, is environmentally acceptable, possessing no hazardous or toxic effects. When the bubble/cell size is made on a nanometer scale, nanocellular polymers are generated, which can exhibit superior structural, mechanical, optical, electrical and corrosion-resistant properties. Despite numerous advantages of micro/nanocellular foams, the research and development of these polymers are still at their infancy. The chief reason for not being able to manufacture desired sub-micro or nanocellular foams is the poor understanding of the mechanisms underlying the foaming process. Thus, our short term objectives are to understand the micro/nanocellular foaming mechanisms of polystyrene in supercritical CO2, demonstrate model predictions of lab-scale experiments, and test the optimized protocol in the extruder or injection molding processing. Our long term objectives are to implement the developed polymer foaming protocol/technology in the industry-scale processing at Mastercore, the industrial partner, and expand the polymer investigated to other commercial polymers, e.g., polyethylene (HDPE and LDPE) and polypropylene in supercritical CO2 and N2. The research outcome will provide necessary processing/materials/system requirements for manufacturing polymer foams of controlled cell size, distribution and density. This will represent a major breakthrough in producing lightweight, multifunctional micro/nanocellular polymers, which are suitable for a variety of industrial applications. The resulting technology will allow our industrial partner and Canadian plastics manufacturers to advance their polymer foaming processes, propelling them to the forefront of the international competition in the broader area of plastics processing and manufacturing.