Effect of boric acid on thermal behavior of copper nanopowder/epoxy composites

The epoxy composites were synthesized from epoxy resin ED-20, polyethylene polyamine as curing agent and copper nanopowder and boric acid as fillers. The copper nanopowder was produced by electrical explosion of wires. The thermal properties of the epoxy composites at the heating in the atmosphere of air and argon from ambient temperature to 900 °C were characterized using thermogravimetric analysis and differential scanning calorimetry. The results showed that copper nanopowders catalyzed thermal oxidative degradation of the epoxy composites. The effect of the addition of boric acid in the epoxy polymer filled with copper nanopowder on the thermal stability of the composite at the heating in air was studied. It was found that the boric acid addition inhibited the degradation process. The limiting oxygen index was calculated in accordance with Van Krevelen and Hoftyzer equation.