Polymerization within a molecular-scale stereoregular template

Enzymes efficiently synthesize biopolymers by organizing monomer units within regularly structured molecular-scale spaces and exploiting weak non-covalent interactions, such as hydrogen bonds, to control the polymerization(1) process. This 'template' approach is both attractive and challenging for synthetic polymer synthesis, where structurally regulated molecular-scale spaces could in principle provide solid-phase reaction sites for precision polymerization. Previously, free-radical polymerization of methyl methacrylate in solutions containing stereoregular isotactic ( it) or syndiotactic (st) poly( methyl methacrylate) ( PMMA) has been shown to result in template synthesis(2,3) of the opposite PMMA based on stereocomplex formation(4,5) with van der Waals interactions. However, using the structure of a solid to determine the stereochemical structure of a polymer has not been satisfactorily achieved(6). Here we show that macromolecularly porous ultrathin films, fabricated by a single assembly step, can be used for the highly efficient stereoregular template polymerization of methacrylates through stereocomplex formation. This reaction mould accurately transfers its structural properties of stereo-regularity, molecular weight and organization within the template to the new polymer.