This work studies the properties of poly(n-butyl acrylate) functionalized with 2,6-bis(1′-methylbenzimidazolyl)pyridine ligand and cross-linked with either copper(II), zinc(II), or cobalt(II) metal ions. Because of phase separation between the metal–ligand complex and the polymer matrix, these polymers have a rubbery plateau modulus that is 10 times higher than expected based on the theory of rubber elasticity. Differences in the metal–ligand bond strength influence the mechanical behavior at high temperature and strains. Because of the particularly weak bond strength associated with the copper–ligand bond, the metallopolymer containing copper degrades at a lower temperature and has lower yield strength, ultimate tensile strength, and creep resistance than polymers containing cobalt and zinc. To tune the properties of the polymer further, a polymer is made with both copper and cobalt ions. The hybrid polymer combines the properties of the stiffer cobalt-containing polymer with the more compliant copper-containing polymer.

We performed atomistically detailed molecular dynamics simulations to study adsorption behaviors of catechol, which is a key functional group in marine bioadhesives, to two different alumina surfaces in both anhydrous and aqueous conditions. In anhydrous conditions, without competing interactions from water molecules, catechol adsorbed to both hydroxylated and nonhydroxylated alumina surfaces. In aqueous conditions, catechol and several analogous phenolic compounds displaced water molecules and were strongly attracted to the nonhydroxylated alumina surface, which is more hydrophobic. When comparing the phenolic moieties near the hydroxylated alumina surface in aqueous conditions, the catechol molecules displayed the strongest adsorptions mainly through cooperative hydrogen bonding interactions of two neighboring hydroxyl groups with the surface hydroxyl groups of alumina as evidenced by the longer hydrogen bonding lifetimes and the larger number of adsorbed molecules near the surface. Insights gained from this study can be used in design of novel bioadhesives or antifouling surface coatings.

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We present electronic structure calculations of the ultraviolet/visible (UV-vis) spectra of highly active push-pull chromophores containing the tricyanofuran (TCF) acceptor group. In particular, we have applied the recently developed long-range corrected Baer-Neuhauser-Livshits (BNL) exchange-correlation functional. The performance of this functional compares favorably with other density functional theory (DFT) approaches, including the CAM-B3LYP functional. The accuracy of UV-vis results for these molecules is best at low values of attenuation parameters (γ) for both BNL and CAM-B3LYP functionals. The optimal value of γ is different for the charge-transfer (CT) and π-π* excitations. The BNL and PBE0 exchange correlation functionals capture the CT states particularly well, while the π-π* excitations are less accurate and system dependent. Chromophore conformations, which considerably affect the molecular hyperpolarizability, do not significantly influence the UV-vis spectra on average. As expected, the color of chromophores is a sensitive function of modifications to its conjugated framework and is not significantly affected by increasing aliphatic chain length linking a chromophore to a polymer. For selected push-pull aryl-chromophores, we find a significant dependence of absorption spectra on the strength of diphenylaminophenyl donors.