Tetrafunctional cardo epoxy resin (EBCF) was cured by using 10 wt% maleic anhydride (MA), pyromellitic dianhydride (PMDA), phthalic anhydride (PA), tetrahydrophthalic anhydride (THPA), tetrabromophthalic anhydride (TBPA), and tetrachlorophthalic anhydride (TCPA) as hardeners at 120°C for 40–105 min (gel time) and then postcured 1 h at 130°C. Gel time is found to depend on the structure of the anhydrides used. Cured samples were found insoluble in common solvents. Cured and uncured EBCF were characterized by FTIR, DSC, and TGA techniques. Cured and uncured resins followed multistep degradation reactions. Kinetic parameters, namely, order of degradation, energy of activation, frequency factor, and entropy change, were determined according to the Anderson-Freeman method and interpreted in light of the nature of hardeners used for curing purpose. The resins followed integral or fractional order degradation kinetics. Complex degradation reactions are due to different types of linkages in cured resins. Both nature and structure of resin and hardeners affected the curing behavior and the resultant thermal properties of the cured resins. 1. Introduction Epoxy resins are well known for their outstanding processing behavior and physicochemical properties such as mechanical stiffness and toughness; chemical, moisture, and corrosion resistance. They are most widely used in advanced technologies, aerospace, electronics, communication, adhesives, primers, coatings, and semiconductor encapsulation industries. They are also used for storage and management of nuclear waste as matrices for advanced fiber-reinforced composites [1–6]. The basic properties of epoxy resins can be modified by blending different resins, by selection of curing agents, and by the use of modifiers and fillers. Multifunctional epoxy resins are well known for their high glass transition temperatures, high decomposition temperatures, long term high temperature performance, and good wet strength performance [7–11]. These materials suffer two important limitations because of their intrinsic brittle nature and considerable moisture absorption tendency from environment, which adversely affect most physicomechanical properties of the fabricated articles. Both these drawbacks increase by enhancing the crosslink density of the network. To the best of our knowledge, no work has been reported on anhydrides cured multifunctional epoxy resin containing cyclohexyl as a cardo (Latin meaning a loop) group, which encouraged us to investigate the present work. In this paper, we have reported curing study of cardo
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