Two diglycidyl ethers of carborane bisphenols (1 and 2) were synthesized via a two-step method from carborane bisphenols and epichlorohydrin. The obtained carborane-containing epoxy resins were characterized with spectroscopic techniques including FTIR

1H-NMR

and GPC which give satisfactory results. When the etherification step of the synthesis of 1 and 2 was conducted at 100 ℃ for 2 and 3 h respectively

resins with the highest epoxy value

0.366 for 1 and 0.381 for 2

were obtained. 4

4'-Diaminodiphenylsulfone (DDS) was utilized as curing agent and the curing kinetics studies show that the activation energy (Ea) of 1/DDS and 2/DDS were calculated to be 79.0 and 67.1 kJmol-1 which are higher than that of E-51/DDS

indicating that the carborane structure plays a negative role in the reactivity of epoxy resins. On the basis of Ea values

the optimum curing condition is determined to be 180℃/2h+200℃/2h. DSC results show that Tg of 1/DDS and 2/DDS are 175.8 and 167.6 ℃

which are higher than that of TDE-85 (154.1℃).The introduction of carborane endows epoxy resin with ultrahigh char yield. Particularly

the char yield of the obtained carborane-containing epoxy resin under air is higher than that under nitrogen. For example

2 shows char yield of 65.4% and 78.7% at 700 ℃ under nitrogen and air

respectively. This could be explained by the fact that the carborane cage could react with oxygen to form BOB structure

which further postpones the thermal decomposition of epoxy resin and accounts for the high char yield.