19 research outputs found
Thermal Stability, Rheology and Morphology of Metallo-Supramolecular Polymers Based on bis-Terpyridine Ruthenium (II) Complexes
Supramolecular polymers, based on poly(ethylene glycol) and terpyridine-ruthenium(II) complexes, were investigated regarding their thermal stability by TGA. In addition, the temperature-dependent melt viscosity was studied using a rheometer and the results were compared to the corresponding classical poly(ethylene glycol). Finally, the morphology of an annealed film was investigated by AFM
Surface structuring and coating performance: novel biocidefree nanocomposite coatings with anti-fouling and fouling-release properties
State-of-the-art coatings consist of all kinds of ingredients amongst which (inorganic) filler particles are important additives. Knowledge of particle modification and chemistry of the coating formulation allows tailoring the coating properties and thus its performance and applicability. Recently nanocomposite coating systems were produced by introduction of anisotropic nanoparticles. These nanoparticles (sepiolite) are ionically and/or covalenty functionalised with one or more different organic groups, i.e. providing the particle with more than one function. By the introduction of coating compatible and coating incompatible modifiers a structured coating can be obtained. In this paper the modification of anisotropic particles will be presented as well as the effect of the type of particle modification on surface properties of a sol-gel based coating. The obtained surface structures of the coatings were evaluated on their anti-fouling and fouling-release properties. The adherence and ease of removal by hydrodynamic shear forces were determined for marine bacteria. The coatings were found to inhibit settlement of the marine bacteria and showed promising results with respect to fouling-release properties in comparison with state-of-the-art fouling-release coatings and anti-fouling coatings. © 2009 Elsevier B.V. All rights reserved
High molecular weight supramolecular polymers containing both terpyridine metal complexes and ureidopyrimidinone quadruple hydrogen-bonding units in the main chain.
Using a hydroxy-functionalized terpyridine as initiator, a poly(e-caprolactone) containing one terpyridine endgroup was prepared by tin octanoate-catalyzed controlled ring-opening polymerization. The ¿-hydroxy group of this polymer was subsequently reacted with an isocyanato-ureidopyrimidinone, resulting for the first time in polymers bearing a metal-coordinating ligand on the one and a hydrogen-bonding unit on the other chain end. Hydrogen-bonded supramolecular dimers were shown to be present in chloroform solution. The subsequent addition of iron(II) ions resulted in the formation of high molecular weight supramolecular polymers with novel properties resulting from the combination of both types of noncovalent interactions in the main chain, as could be shown using capillary viscosimetry and rheometry
Study of wettability and improvement of adhesion of UV curable powder coatings on polypropylenen substrates
Different benzophenone type photoinitiators were photografted onto polypropylene. The polymer surfaces were analysed by means of contact angle measurements, UV spectroscopy, and FTIR-ATR. The modified samples showed a better wettability and higher surface energies increasing from 26 mN/m for pure polypropylene up to 36 mN/m for the modified samples. Different acrylates were grafted efficiently onto the modified polymer surfaces. FTIR-ATR and contact angle measurements confirmed the presence of the grafted chains. The surface energy of the grafted surfaces samples increased then up to 70 mN/m depending of the type of acrylate used. Finally UV curable powder coatings were applied onto the modified polypropylene substrates and the adhesion was improved. Adhesion was measured by pull-off tests and values of 0.20 MPa were obtained for pure polypropylene while the modified polypropylene reach pull-off values of 2.00 MPa
Thermal Stability, Rheology and Morphology of Metallo-Supramolecular Polymers Based on bis-Terpyridine Ruthenium (II) Complexes
Supramolecular polymers, based on poly(ethylene glycol) and terpyridine-ruthenium(II) complexes, were investigated regarding their thermal stability by TGA. In addition, the temperature-dependent melt viscosity was studied using a rheometer and the results were compared to the corresponding classical poly(ethylene glycol). Finally, the morphology of an annealed film was investigated by AFM
Metallo-supramolecular coordination polymers: morphology, thermal behavior and rheology
Linear coordination polymers are interesting materials with respect to a wide variety of different applications due their electronic, photophys., magnetic and catalytic properties. The incorporated metal-complex moiety provides furthermore the possibility for a switching between monomeric units and the polymer upon external stimuli such as pH-changes, UV irradn., application of elec. potential or simply concn. changes. Here we present morphol. studies of thin films of metallo-supramol. polymers, their thermal behavior and their changes of rheol. upon heating
Metallo-supramolecular coordination polymers: morphology, thermal behavior and rheology
Linear coordination polymers are interesting materials with respect to a wide variety of different applications due their electronic, photophys., magnetic and catalytic properties. The incorporated metal-complex moiety provides furthermore the possibility for a switching between monomeric units and the polymer upon external stimuli such as pH-changes, UV irradn., application of elec. potential or simply concn. changes. Here we present morphol. studies of thin films of metallo-supramol. polymers, their thermal behavior and their changes of rheol. upon heating