How the physical confinement of phenolic resin in nano porous silica (8 nm Յ pore diameter (D p ) Յ 125 nm) affected the polymer's curing behavior was examined by conducting differential scanning calorimetry experiments at 320 K Յ T Յ500 K. Our results suggested that upon incorporating the phenolic resin into the silica, its curing temperature was lowered. However, what was interesting was that there was an inverse linear dependence between the pore size and the curing temperature, i.e., the smaller the pore diameter the higher the curing temperature. There was evidence that phenolic resin was unable to penetrate into 8 nm-sized pores.