Mechanical and thermal properties improvement of unsaturated polyester resin by incorporation of TiO₂ nanoparticle surface modified with titanate

Unsaturated polyester resin (UPR)/titanium dioxide (TiO _2 ) nanocomposites were obtained by the incorporation of TiO _2 nanoparticle surface modified with titanate in the UPR. The mechanical properties, thermal behavior, anti-ultraviolet aging properties and composite microstructure were tested. The results show that TiO _2 nanoparticles have a good compatibility with the UPR matrix. When the contents of TiO _2 and titanate coupling agent are 4% and 3% respectively, the impact strength, flexural strength and heat deflection temperature of the composites are 16.28 kJ m ^−2 , 63.23 MPa, and 70.3 °C, respectively, which increase by 890.5%, 77.5% and 23.7% compared with pure UPR. The incorporation of modified TiO _2 nanoparticles in the UPR enhances the anti-ultraviolet aging properties of the composites. When 4% TiO _2 nanoparticles are added to the UPR, the impact strength retention rate improves by 29.8% compared with pure UPR at 60 days. Strengthening and toughening effects with the incorporation of TiO _2 can be achieved by forming a flexible interface layer between the TiO _2 and UPR matrix because of the higher rigidity, excellent bonding and compatibility of the TiO _2 .