Thermally Stable Polyureas and Poly(urea-imide)s Containing Zinc and Nickel Napthtrien Complexes

摘要

Two new napthtrien metal complexes, MNapth(2)trien; where M = Zn and Ni, were synthesized and used for the synthesis of metal-containing polyureas and poly(urea-imide)s. MNapth(2)trien underwent polymerization reaction with two diisocyanates, namely, 4,4'-diphenylmethane diisocyanate and isophorone diisocyanate to yield polyureas. Poly(urea-imide)s were obtained by the synthesis of metal-containing isocyanate-terminated polyurea prepolymers from the reaction between MNapth(2)trien and excess diisocyanates, which could then undergo further reaction with different dian-hydrides. The dianhydrides used were pyromellitic dianhydride and benzophenone-3,3',4,4'-tetracarboxylic dianhydride. The polymers were characterized by infrared, nuclear magnetic resonance, elemental analysis, X-ray diffraction, solubility, and viscosity. Glass transition temperature of the polymers was obtained from differential scanning calorimetry and dynamic mechanical thermal analysis. Thermal stability of polymers was studied by thermogravimetric analysis in air. It was found that the resulting metal-containing polymers exhibited good thermal stability. Initial decomposition temperatures of the polymers depend on the amount of MNapth(2)trien in the polymer composition. Char yields of metal-containing poly (urea-imide)s are higher than those of metal-containing polyureas. Most metal-containing polymers show good solubility in organic solvents. Shore D hardness test indicates that metal-containing poly(urea-imide)s are hard materials.