Solid-State Shear Pulverization

This book is the first extended look at a new and multifaceted polymer processing technology that has already been discussed in numerous articles. Called Solid-State Shear Pulverization (S3P), this innovative process produces polymeric powders with unique physical properties not found in the output of conventional size-reduction methods.... This technology, which utilizes a pulverizer based on a modified co-rotating twin-screw extruder..., has profound implications for both the creation of new polymer blends and recycling of plastic and rubber waste. Unlike [earlier processes] where polymers are melted prior to pulverization, ...pulverizing mixtures of polymers with the S3P process...does not involve melting. By contrast, S3P maintains polymers in the solid state and avoids the additional heat history that occurs during [other processes], which can be detrimental to the physical properties of pulverized materials. The research and development of the S3P technology...has grown significantly since 1990 from the development of a new plastics recycling process to a much broader polymer processing method that allows intimate mixing of polymers with very different viscosities, sold-state dispersion of additives, including pigments, and continuous production of powder with unique shapes and larger surface areas. Polymeric powders are of growing importance to plastics processors due to the increase use of plastics in various applications, such as rotational molding, powder coatings, and compounding, which require powder as the feedstock. The Authors Klementina Khait, M.S. Ch.E., Ph.D., is Research Associate Professor and Director of the Polymer Technology Center in the Department of Chemical Engineering, Northwestern University. Her industrial experience in polymer science and engineering includes work with Borg-Warner Chemicals and Quantum Chemical Corporation. She received her two advanced degrees, in chemical engineering and polymer chemistry, from the Technological Institute, St. Petersburg, Russia. Dr. Khait holds several patents and has published more than 50 papers in scientific and technical journals. Stephen Carr, Ph.D., is Professor of Materials Science and Engineering and Chemical Engineering at Northwestern University. His industrial work includes work in polymer science and engineering with General Motors Corp. He received a doctorate in polymer science from Case Western Reserve University. He has been on the Northwestern University faculty since 1969. Martin H. Mack is Vice President for R&D with the Berstorff Division of Krauss-Maffei Corporation. He holds an engineering degree from the University of Stuttgart. He has served for more than ten years on the Board of Directors of the Society of Plastics Engineers (SPE).