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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)).

Core/shell nanoparticles containing the fungicide tebuconazole were prepared from amphiphilic copolymers of gelatin grafted with MMA. The grafting was performed in water at levels of 1.5–15 wt.‐% solids based on matrix mass, to give core/shell nanoparticles with median diameters ranging from ≈200 to 400 or ≈10 to 100 nm depending on composition, conditions used, and work‐up. The biocide‐containing nanoparticles were delivered into wood in up to 85% efficiency. Wood blocks treated with tebuconazole‐containing nanoparticles leached less tebuconazole than wood blocks treated with tebuconazole solutions. The best nanoparticle formulations afforded wood blocks with a biological efficacy comparable to solution‐treated wood block controls in soil jar decay tests.