The synthesis of AB diblock copolymer polyampholyte polymer brushes of the type Si/SiO2//poly(acrylic acid-b-vinyl pyridine) prepared using atom transfer radical polymerization is reported. Both 2- and 4-vinyl pyridine have been used. The diblock polyampholyte polymer brushes demonstrate stimuli-responsive behavior with respect to pH, showing both polyelectrolyte and polyampholyte effects. Furthermore, we have quaternized the 4-vinyl pyridine segments to form a mixed weak/strong, or annealed/quenched, polyelectrolyte system. The quaternized polymer brush exhibits different pH-responsive behavior, with decreasing film thickness being observed with increasing pH.

Polymers are widely used as insulators in electronic devices. Low dielectric constant polymers are desirable since this lowers the potential for unintentional crosstalk and inductive coupling between conductors. Attempts to photopattern a low dielectric constant polymer, poly(5-hexyl-2-norbornene) (poly(1)), with a bis(azide) were unsuccessful. Incorporation of butenyl pendent groups improved patterning, but the dielectric constant of the cross-linked film was relatively high (2.60). A difunctional bis(diazirine) (compound 4) was synthesized and characterized by NMR and MS. Compound 4 rendered unreactive, aliphatic cycloolefin polymers such as poly(1) photopatternable, yielding negative tone patterns with good resolution. The dielectric constant of films cross-linked with compound 4 was substantially lower than the films cross-linked with bis(azide) (2.09 for poly(1)).

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The norbornenyl gluconamide (NBGA) monomer can be polymerized by a number of palladium catalysts to give water-soluble, vinyl addition poly(NBGA). Depending on the catalyst used, the reaction conditions, and the chain-transfer additives employed, high-molecular-weight polymers can be obtained. These polymers can be thermally cross-linked at ca. 190 °C or at ca. 150 °C when the difunctional glutaraldehyde is added. A photopatternable composition is formed by the addition of a water-soluble diazide when the poly(NBGA) molecular weight is sufficiently high. After image-wise exposure, negative-tone patterns are revealed by water development. A detailed analysis of NBGA monomer structures by high-resolution nuclear magnetic resonance techniques including pure shift is reported showing that two diastereomers of each endo- and exo-isomer are formed from the reaction of norbornene methylamine and δ-gluconolactone.