Synthesis of polyurethanes containing manganese and nickel 4,4'-dihydroxysalcyclohexane complexes

Abstract

4,4'-Dihydroxysalpentaen metal complex (ML1) was synthesized from 2,4- dihydroxybenzaldehyde, metal (II) acetate, where M were Mn2+ and Co2+, and pentaethylenehexamine. The purity of these synthesized complexes was not good and therefore they were not used in the polymer synthesis. Then, the new metal complex, 4,4'-dihydroxysalcyclohexane metal complex (ML2), was chosen. ML2 was synthesized from the reaction between 2,4-dihydroxybenzaldehyde, metal (II) acetate, where M were Mn2+ and Ni2+, and 1,2-diaminocyclohexane. ML2 was characterized by IR spectroscopy, elemental analysis and MALDI-TOF MS. Metal-containing polyurethanes have been synthesized by the reaction between ML2 and isocyanate-terminated prepolymers with dibutyltin dilaurate as a catalyst. The isocyanate-terminated prepolymers used were tolylene 2,4-diisocyanate terminated poly (l,4- butanediol) (PB), MW 900 and tolylene 2,4-diisocyanate terminated poly(propylene glycol) (PP), MW 1000. Characterizations of polymers were carried out using IR spectroscopy. Thermal stability was studied by thermogravimetric analysis (TGA). It was found that metal-containing polyurethanes showed good thermal stability.