From the Preface
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.
…[I]t has become clear that this process allows for in-situ compatibilization of dissimilar polymers by applying mechanical energy to cause chemical reactions. This aspect of S3P technology that we describe in this book should [be useful in] developing new polymer blends with the use of pre-made compatibilizing agents. In addition, it has been discovered that S3P efficiently mixes polymer blends with different comp