How should one approach the engineering of macromolecular materials that combine the very different virtues of natural and synthetic polymers? Natural polymers, especially proteins an nucleic acids, serve as selective catalysts and as efficient information storage devices, while their synthetic counterparts (polyethylene, polypropylene, and so on) dominate modern materials technology because of their excellent mechanical, barrier, and processing behaviors (Rodriguez, 1996). The molecular architectural features that underlie these disparate patterns of behavior are strikingly different: proteins and nucleic acids are characterized by precisely defined chain lengths and sequences, whereas synthetic polymeric materials consist of complex mixtures of chain molecules in which length, sequence, and stereochemistry (molecular shape) vary widely from chain to chain.
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