Studies on Bismaleamic Acids Cured Tetrafunctional Epoxy Resin of Bisphenol‐C and Glass‐Epoxy Composites

ABSTRACT The tetrafunctional epoxy resin of bisphenol‐C was cured using bismaleamic acids of maleicanhydride and 4,4'‐diaminodiphenylsulfone, 4,4'‐diaminodiphenylether, and 4,4'‐diaminodiphenylmethane and characterized by infrared, differential scanning calorimetric, and thermogravimetric analysis. Cured resins showed endothermic transition at about 229–248°C, which supplemented decomposition reactions. Cured resins are thermally stable up to about 200–230°C and followed two‐step decomposition reactions. A 34–56% residue at 600°C supplemented the formation of highly thermally stable cross‐linked products. Glass composites showed 133–153 MPa tensile strength, 223–290 MPa flexural strength, 7520–8015 MPa flexural modulus, 33–38 kg m −2 impact strength, 37–40 Barcol hardness, 8.3–12.3 kV mm −1 electric strength, 8.9 × 10 12 to 4.2 × 10 14 ohm cm volume resistivity, and 13–14% water absorption. Good thermal, mechanical and electrical properties and excellent hydrolytic stability of the glass composites signify their industrial importance for low load bearing housing, electrical, and marine applications.