Effects of nano-TiO2 on bonding performance, structure stability and film-forming properties of starch-g-VAc based wood adhesive

The nano-TiO2 was utilized to improve the bonding performance, structure stability and film-forming properties of renewable starch-based wood adhesive. The results showed that 4% nano-TiO2 (nano-TiO2: starch, w; w) resulted in 6.5 MPa of shear strength and 6437 Pa.s of viscosity. The thermal stability was measured by thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). Additionally, low-field nuclear magnetic resonance (NMR) and rheological results exhibited the enhancement of nano-TiO2 on the pseudoplasticity and structure which determined the state and migration of water. Besides, the structural characterization of copolymer was analyzed via fourier transform infrared spectroscopy (FTIR) and X-ray diffraction analysis (XRD). Furthermore, the film-forming property was evaluated by small angle X-ray scattering (SAXS) and dynamic mechanical analysis (DMA). The morphological structures of adhesive were observed by scanning electron microscopy (SEM). In conclusion, the 4% nano-TiO2 (nano-TiO2: starch, w; w) can be employed to prepare starch-based wood adhesives with superior properties for wood application.