Effect of γ-irradiation on the thermo-oxidative behavior of nano-silica based urea–formaldehyde hybrid composite with 4-chloro-3-nitro-2H-chromen-2-one

Two types of nano-silica based urea–formaldehyde (UF) hybrid composite materials with formaldehyde to urea (F/U) ratio (0.8) were synthesized without (UF + SiO2) and with coumarin (UF + SiO2 + 4-chloro-3-nitro-2H-chromen-2-one). Nano-silica based UF hybrid composites have been irradiated (50 kGy) and effect of γ-irradiation was evaluated on the basis of thermo-oxidative behavior before and after irradiation. The thermo-oxidative behavior of materials was studied by non-isothermal thermo-gravimetric analysis (TG), differential thermo-gravimetry (DTG) and differential thermal analysis (DTA) supported by data from IR spectroscopy. After γ-irradiation, the shift of temperature values for selected mass loss to a higher temperature indicates that thermo-oxidative stability of modified nano-silica based UF resin with coumarin 4-chloro-3-nitro-2H-chromen-2-one is increase.