People

Finally, we are interested in understanding solid state processing (at temperatures lower than the melting point of a polymer) of polymeric materials for economic production with enhanced material properties. Although many attempts to apply the concept of solid state processing to many polymeric systems have been made for several decades, the practical impact of the process has been rather insignificant, because the lack of productivity seems to be inherently imbedded in the process. The interplay between material preparation and process development is the key here, and one good example of this interplay in solid state processing is the synthesis of ultra high molecular weight polyethylene (UHMWPE) for which the yield is high even at relatively low polymerization temperatures (Figs. 14 and 15). Such UHMWPE nascent reactor powders can directly be processed to continuous multi-stage orientation drawing to produce high strength, high modulus materials or microporous membranes (Figs. 16 and 17). Finite element analysis of solid-state drawing, which incorporates stress induced crystallization and morphology evolution, is applied to predict the structure and properties of the product.