Surface-Modified TiO₂@SiO₂ Nanocomposites for Enhanced Dispersibility and Optical Performance to Apply in the Printing Process as a Pigment

The grafted modification TiO2@SiO2 compositewas fabricated by a liquid-phase deposition method with Na2SiO3 and a grafting reaction with a silane coupling agent.First, the TiO2@SiO2 composite was prepared,and the effect of deposition rate and silica content on the morphology,particle size, dispersibility, and pigmentary property of TiO2@SiO2 composites was investigated by scanning electronmicroscopy (SEM), transmission electron microscopy (TEM), Fouriertransform infrared (FTIR) spectroscopy, energy-dispersive X-ray spectroscopy(EDX), X-ray photoelectron spectroscopy (XPS), and zeta-potential.The islandlike TiO2@SiO2 composite had a goodparticle size and printing performance compared with the dense TiO2@SiO2 composite. The presence of Si was confirmedby EDX elemental analysis and XPS, and a peak at 980 cm(-1) belonging to Si-O was observed in the FTIR spectrum, confirmingthe presence of SiO2 anchored at TiO2 surfacesvia Si-O-Ti bonds. Then, the islandlike TiO2@SiO2 composite was modified by grafting with a silanecoupling agent. The effect of the silane coupling agent on the hydrophobicityand dispersibility was investigated. The peaks at 2919 and 2846 cm(-1) belong to CH2 in the FTIR spectrum, andSi-C in the XPS confirmed the grafting of silane coupling agentto the TiO2@SiO2 composite. The grafted modificationof the islandlike TiO2@SiO2 composite using3-triethoxysilylpropylamine endowed it with weather durability, dispersibility,and good printing performance.