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The nanometer carbon black (CB) was employed to prepare epoxy resin/carbon black (EP/CB) composites by blending-casting method. The different modified methods of silicone coupling agent were used to improve the dispersion of CB in epoxy resin. The mechanical and thermal properties of EP/CB composites were investigated. Experimental results showed that the mechanical properties increased at first, but decreased with excessive addition of CB. When the mass fraction of CB was 2%, the mechanical properties were maximum. The use of modified CB significantly enhanced the mechanical properties of the composites. For given CB loading, the CB modified by pretreatment method displayed better dispersion in the epoxy resin than that of the direct mixing method. SEM observation revealed that the tensile fracture surface of the composite filled with 2 wt% modified CB held more microcracks than that of 5 wt% modified CB, and the formed microcracks could consume more energy of rupture, finally to have better tensile strength. DSC analysis showed that the glass transition temperature (Tg) of the composites increased with the increasing mass fraction of CB. [ABSTRACT FROM AUTHOR]

The aluminum nitride (AlN) was employed to prepare epoxy/AlN composites by blending-casting moulding method, two different coupling agents were used to functionalize the surface of AlN. The thermal conductivity and mechanical properties of the composites were investigated. And the cure kinetics of the EP/AlN composites was studied by means of isothermal DSC. Results revealed that the thermal conductivity of EP improved remarkably with the addition of AlN, a higher thermal conductivity of 1.05 W/mK can be achieved with 42 vol% AlN, about 5 times higher than that of native epoxy resin. And the flexural and impact strength of the EP/AlN composites were optimal with 3.3 vol% AlN. The curing process of the EP/AlN composites contained autocatalytic mechanism, the whole process was according with the Kamal model. The presence of AlN did not change the cure reaction mechanism, and had little effecting on the activation energy, but decreased the rate constants kl and k2. [ABSTRACT FROM AUTHOR]