Polystyrene supramolecular networks based on DA-AD hydrogen bonds

International audienceThen polystyrene supramolecular networks were prepared by radical copolymerization of styrene with monomers containing donor–acceptor (DA) moieties methacrylamide (MAAM) or 2-methacrylamidopyridine (MAP). The molar percentages of MAAM and MAP in the copolymers were, respectively, 2–20% and 6–40%. The glass transition temperatures (Tgs) of these copolymers have been modeled by the Kwei equation showing secondary interactions due to intermolecular hydrogen bonds. The DA-AD association constants (K) have been calculated by 1H NMR spectroscopy of MAAM and MAP. These constants were, respectively, 6.75 and 16.75 M−1. Dynamic mechanical analyses by frequency and temperature sweep tests, were carried out in the molten state. Styrene–MAP or styrene–MAAM copolymers had higher moduli than neat polystyrene but the MAP influences the materials’ properties distinctively from the MAAM. MAP copolymers had a second G′ plateau that appeared at 150 °C, thus showing the formation of a supramolecular network