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To modify carbon black surface, the surface grafting of hyperbranched poly(amidoamine) onto the surface by using dendrimer synthesis methodology was investigated. Carbon black having amino groups (initiator sites) was prepared by the reduction of surface nitro groups introduced by nitration of aromatic rings. It was found that hyperbranched poly(amidoamine) was propagated from carbon black surface by repeating two processes: (1) Michael addition of methyl acrylate (MA) to surface amino groups and (2) amidation of the resulting esters with ethylenediamine: the percentage of poly(amidoamine) grafting reached to 96.2% after 10th‐generation. The grafting of hyperbranched poly(amidoamine) onto polystyrene‐bead as a model compound of carbon black was also achieved by the above procedures. However, the theoretical propagation of poly(amidoamine) dendrimer was not achieved, because of steric hindrance of grafted polymer. Hyperbranched poly(amidoamine)‐grafted carbon black gave a stable dispersion in a good solvent for poly(amidoamine). Copyright © 2001 John Wiley & Sons, Ltd.

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Spontaneous homopolymerization of 2,5‐dimethylene‐2,5‐dihydrofuran (DDF) was studied. The polymerization rates in two different initial monomer concentrations of DDF were analyzed with the first‐order and second‐order kinetics, and the homopolymerization of DDF was found to obey the first‐order kinetics. The Arrhenius plot of the apparent rate constants at 30, 40, 50, and 60° gave an overall activation energy of 68.0 kJ/mol for the polymerization of DDF. From the comparison of the apparent rate constants at –78° and the time (the so‐called half‐life time) to decrease in half the monomer concentration for DDF with the corresponding values for p‐xylylene (QM), DDF was found to be a less reactive monomer than QM. The copolymerizations of DDF with vinyl monomers such as acrylonitrile (AN), α‐chloroacrylonitrile (CIAN), diethyl fumarate (DEF), and fumaronitrile (FN) were carried out in chloroform at 50° in the presence of AIBN to obtain the monomer reactivity ratios r1(DDF) = 30.0 ± 3.0 and r2 (AN) = 0 for the DDF‐AN system, r1 (DDF) = 1.55 ± 0.2 and r2(CIAN) = 0 for the DDF‐CIAN system, r1(DDF) = 3.88 ± 0.2 and r2(DEF) = 0 for the DDF‐DEF system, and r1(DDF) = 2.41 ± 0.1 and r2 (FN) = 0 for the DDF‐FN system, respectively. As the monomer reactivity ratios of r2 for all systems were zero, Q and e values of DDF were calculated from the combination of two r1 (DDF) values of any two copolymerization systems to be the 7.64 to 6.63 ×1021 range for Q and the –0.70 to –6.31 range for e, indicating that DDF is a highly conjugative and electron‐donating monomer. © 1995 John Wiley & Sons, Inc.

The adhesion between a silicon nitride layer and polycarbonate substrate was improved by employing a silicon interfacial layer which was deposited by a microwave plasma enhanced chemical vapor deposition technique. The silicon interfacial layer had an interpenetrating layer composed of the two materials, which provided an anchoring effect. In the interpenetrating layer, it was assumed that chemical bonding between carbon of the polycarbonate substrate and the silicon interfacial layer occurred through the oxygen when the radio frequency power was used in the fabrication process. The oxygen originated in the polycarbonate substrate. During the silicon interfacial layer deposition, carbon was sputtered and oxygen reacted with silicon.