Synthesis, spectroscopic and thermal characterization of new metal-containing isocyanate-based polymers

Abstract

© 2017, Akadémiai Kiadó, Budapest, Hungary. To overcome the polyurethanes low heat resistance and obtain new PU-based materials, in continuation of our research in the synthesis of hybrid polymers, we report here the synthesis of metal-containing polyurethanes formed in the reaction of pyrazole-based coordination compounds [Cuampf(NO3)2MeOH]·MeOH and [CuampfCl2] where ampf denotes N,N′-bis(4-acetyl-5-methyl pyrazole-3-yl)formamidine ligand, and two isocyanates, 1,6-diisocyanatohexane (HDI) and Bayhydur 3100 (Bay, a hydrophilic linear polymer based on 1,6-diisocyanatohexane) using dibutyltin-dilaurate catalyst. The formed materials were characterized by FT-IR spectrometry and thermal methods. The formation of the new polymers, besides the corresponding FT-IR spectra, was proved by differential scanning calorimetry (DSC) determining their glass transition temperatures. The thermal decomposition of the materials was examined by simultaneous thermogravimetric (TG) and DSC measurement. For the evaluation of the decomposition mechanism, the data obtained by coupled TG–mass spectrometric (MS) measurements were used. The thermal stability of the hybrid materials based on HDI was found substantially higher than that of the pure 1,6-diisocyanatohexane and decomposition of hybrid materials was more complex, while in the reaction of the metal complexes with Bay the thermal properties of the obtained hybrid polymers were changed only slightly, referring to a small amount of incorporated complexes.