Sodium silicate as catalyst and modifier for phenol-formaldehyde resin

The novel adhesives were prepared using PF resin as matrix and sodium silicate as modification additive. It was proved by Fourier transform infrared spectrometer (FTIR) that silicon-oxygen bonds had been successfully introduced to the structure of PF resin. Boiling water extraction (BWE), scanning electron microscopy (SEM), thermogravimetric analyzer (TGA) and differential scanning calorimetry (DSC) were used to characterize the structure of PF resin modified with sodium silicate (Na2SiO3-PF). The test results show that sodium silicate is an effective modifier to PF resin which lessen the brittleness, accelerate the cure rate and enhance the boiling water resistance of PF resin as well. The FTIR, TGA and DSC test results also show that the structure of PF resin has been changed by sodium silicate.