The risks to human health and environmental hazards associated with VOCs, governmental directives, and economic factors are the main driving forces behind this effort. One way of achieving less or no VOC containing coating systems is to produce low viscosity resins. Hyperbranched resins owing to their globular structure have low viscosities and are promising materials for decreasing the VOCs. In this research hyperbranched resins having properties close to alkyds were synthesized. Dipentaerythritol, which was used as the core was esterified with dimethylol propionic acid. The hyperbranched polyester was then esterified with the castor oil fatty acids v (Castor FA). The hydroxyl group of the ricinoleic acid present in the castor FA was modified with different amounts of linseed oil fatty acids (Linseed FA) and benzoic acid. The chemical characterization of the resins was achieved by FTIR spectroscopy and the thermal properties were determined by DSC. Then, the physical and the mechanical tests were carried out. The resins containing the Castor FA only and 32.5 % Linseed FA in addition to the Castor FA had 24 and 68 Persoz hardness, respectively. The viscosity of the resins decreased from 17.3 Pa⋅s to 5.8 Pa⋅s as the amount of the Linseed FA was increased. The resins showed excellent adhesion, gloss, flexibility and formability.

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Bis(2,4,6-tribromophenolato)di(N-methyl imidazole)M(II), where M stands for cobalt and copper metals, was synthesized via reaction of the corresponding metal sulphate and 2,4,6-tribromophenolate in aqueous media in the presence of N-methyl imidazole and sodium hydroxide. Although various crystallization procedures were applied only cobalt complex was obtained as single crystals. The Co(II) ion has a distorted octahedral enviroment involving two O atoms and two N atoms of the Bis(2,4,6-tribromophenolato)di(N-methyl imidazole) ligand. Powder x-ray diffraction pattern of copper compound was used for cooper complex. For characterizations of complexes carbon, hydrogen and nitrogen elemental analysis, FTIR and UV spectroscopy, DSC thermal analysis and magnetic susceptibility measurements at room temperature were performed.

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