Study On The Effect Of Modified Inorganic Particles On The Performance Of PVB Composite Film

With the development of energy saving and safety requirements of buildings,laminated glass with sandwich structure（i.e.,glass-polymer interlayer-glass）is widely used.The modification of sound and heat insulation of organic/inorganic composites as interlayer substrates is the key to develop laminated glass with sound and heat insulation properties.In this thesis,inorganic nanoparticles such as TiO₂ and SiO₂,which have the function of absorbing and reflecting ultraviolet light,are incorporated into polyvinyl butyral（PVB）film sheets as additives,and their performance in the composites is optimized through modification to achieve sound and heat insulation effects.A series of PVB blends containing different additives were prepared by solution blending method,and the additives TiO₂ and SiO₂ were surface treated with silane coupling agent KH-570 to improve the dispersion performance of the inorganic fillers in the PVB matrix,and then to solve the agglomeration problem between the unmodified inorganic fillers and the matrix resin.And then the effects of modifier and additive dosage on the haze and light transmission,mechanical properties and bond strength to glass of PVB composite film sheets were systematically investigated,and the thermal and acoustic insulation properties of PVB composite film sheets were explored by UV-visible light transmission rate test and acoustic residue test.The surface modification of nano-TiO₂ particles using KH-570,Fourier infrared spectroscopy（FT-IR）test,particle size（DLS）analysis and grafting rate test together proved that KH-570 had successfully grafted onto the TiO₂ surface,and the results of lipophilization test,water contact angle test and dispersibility analysis showed that KH-570 modification conferred hydrophobic and lipophilic properties to TiO₂.When the KH-570 addition amount was 1.0 wt%,the particle size was relatively concentrated,the surface hydrophobicity of TiO₂ was the strongest,and the water resistance of PVB/TiO₂ composite diaphragm was the strongest,and the modification effect under KH-570 addition amount was the best at this time.Metallographic micrographs showed that the modified nano-TiO₂ was well dispersed in the PVB matrix without agglomeration.Tensile tests showed that the addition of TiO₂could significantly improve the mechanical properties of PVB film sheets.The composite film modified with 1.0 wt%KH-570 could block nearly 70%of UV light while achieving more than 80%visible light transmittance,and the thermal insulation effect was 33.3%higher than that of traditional PVB film.The bond strength test results showed that the addition of TiO₂ can strengthen the bonding force of the composite film to the glass.The nano-SiO₂ particles were added to PVB/TiO₂ for synergistic modification,and the effect of the addition of SiO₂ particles on the thermal and sound insulation properties of the composite film sheet at the same particle size was investigated.Infrared and water contact angle tests and dispersion characterization all proved that KH-570 successfully grafted on the TiO₂/SiO₂ surface,making TiO₂/SiO₂ exhibit lipophilic properties.When the nano-SiO₂addition was 10 wt%,the composite diaphragm had the strongest water resistance and mechanical properties,while it could transmit more than 80%of visible light and block more than 70%of UV light,and also blocked 35.4%of noise.The bond strength test results showed that the bond strength between the composite film and the glass exceeds 30 N/cm,which meets the requirements of the national standard.