Preparation and application of micron-sized ZnS-Qds@ polysiloxane core-shell light diffusion hybrid microspheres

In liquid crystal backlight module, diffusion film is usually used to improve the scattering effect of light and improve the utilization rate of light. Light scattering particles are the main factors affecting the transmittance and haze of light scattering materials. Because of its good thermal stability and dimensional stability, particle size and refractive index can be adjusted by reaction, organosilicon microspheres have a very broad application prospect as light diffusion particles in light diffusion materials. Micron-sized ZnS-Qds@polysiloxane core-shell light-diffusion hybrid microspheres were prepared by precipitating a layer of ZnS quantum dot (ZnS-Qds) coated with mercapto polysiloxane on polysiloxane microspheres prepared by sol-gel method. Light diffusion films with different mass fractions of the hybrid microspheres added were prepared. The prepared hybrid materials were characterized by TEM, TEM mapping, fluorophotometer and other testing methods, also tested the optical properties of the light diffusion films prepared with hybrid particles. The results show that ZnS-Qds@polysiloxane light diffusion hybrid microspheres have a core-shell structure with an average particle size of 3.6 µm and an average shell thickness of 87.4 nm. Zns-Qds with an average particle size of 2 nm are uniformly dispersed in the shell layer. The particles are added to the acrylic resin and coated on the polyethylene terephthalate (PET) films to make light diffusion films. The experimental results show that when the added amount of hybrid particles increases from 0wt% to 20wt%, the haze of light diffusion films is greatly improved from 1.67% to 91.11%, but the transmittance of light diffusion films is only slightly reduced from 90.10% to 82.57%. © 2023 Beijing University of Aeronautics and Astronautics (BUAA). All rights reserved.