Effect of schiff's base metal complexes and catalysts on crosslinking reaction of epoxy resin

Abstract

Sodium hydroxide, N,N-dimethylaniline and tetrabutylammonium hydroxide (Bu4NOH) were used as catalysts in the crosslinking reaction of diglycidyl ether of bisphenol-A (DGEBA) with Schiff's base metal complexes of copper, cobalt and nickle. From Differential Scanning Calorimetry (DSC) study, use of the catalysts decreased the crosslinking temperature. The lowest crosslinking temperature was obtained when Bu4NOH was employed. The metal-containing epoxy polymers were synthesized using Bu4NOH at the amount of 20 mole % of the metal complexes. Crosslinking temperatures employed in the preparation of copper, cobalt and nickle-containing epoxy polymers were 150 ํC, 160 ํC and 155 ํC, respectively. The polymer properties were investigated by Dynamic Mechanical Analysis (DMA) and Themogravimetry Analysis (TGA). It was found that the copper-containing epoxy polymer showed the highest glass transition temperature value of 153 ํC, possessed the highest heat resistant with 1.9% weight loss after treatment at 250 ํC for 24 h and showed the best mechanical property, tensile strength of 69 MPa. This copper-containing epoxy showed better physical and mechanical properties than DGEBA/maleic anhydride and DGEBA/diethylenetriamine system.