Preparation of Light‐Diffusing Materials Combined with High Transmittance and High Haze–Comparing the Effectiveness of Diameter and Refractive Index

Abstract Preparing light‐diffusing material (LDM) combined with high haze and high transmittance has a significant value, but it is a challenge for the industry. The refractive index and diameter of light‐diffusing particles are the main factors. Two series of silicone microspheres with different diameters and refractive indices were prepared through precipitation polymerization and applied in LDM. The morphology of particles and LDM were investigated by scanning electron microscope. The corresponding thermal stability was studied by a thermal gravimetric analyzer. Furthermore, the influence of diameter and refractive index on light‐diffusing properties was explored systematically. The results show that the silicone particles have excellent thermal stability and can disperse evenly in a polycarbonate matrix. The corresponding LDM also has good thermal stability. It is the diameter, not the refractive index, acting as the key factor in preparing LDM combined with high haze and high transmittance. When achieving the same haze, selecting an appropriate diameter can prepare LDM with higher transmittance than other diameters. Different refractive indices lead to similar transmittance and haze of LDMs, but the refractive index can markedly affect the loading of particles to achieve an expected light‐diffusing property. This research has aspiring guidance for the industry.