Abstract
TiO(2) is a high-reflectance material for preparing sheets during dry reagent chemical tests in detail. In this study, bifunctional TiO(2) sheets with diffusive and reflective properties were prepared using TiO(2) microspheres (particle size 2-3 µm) and cellulose acetate (CA). Factors such as the CA dosage, water content, mixing time, and the choice of surfactant were investigated. The structure and properties of the bifunctional TiO(2) sheets were characterized by thermogravimetry and differential thermal analysis (TG-DAT), scanning electron microscopy (SEM), dynamic contact angle test and reflectance spectroscopy. By studying the above experimental results, it was concluded that the most optimal preparation conditions for preparing the bi-functional TiO(2) sheets under natural drying conditions were as follows: the mass ratio of CA to TiO(2) microspheres was 0.05:1; Triton-100 was used to improve the diffusion performance of the bifunctional sheets, after mixing for 5 h and coating. The light reflectivity of the bifunctional TiO(2) sheets in the 420 to 800 nm range was higher than 90%. Serum diffused in the bifunctional TiO(2) sheets reacted in the reagent sheets and formed uniform colorful spots. Considering the repeatability of spot proportion and light reflectivity, the sheet offered a uniform serum diffusion and good repeatability. So, the bifunctional TiO(2) sheets are nominated as a promising material for dry chemical diagnostic reagents.