Synthesis And Application Of Nano-silica Coated Composite-particles Of Clay

In the process of coating base paper, the loss of a large number of coated paper to re-reuse, it brought the pigment particles such as clay and calcium carbonate physical properties of the base paper and optical properties of a certain generation. Pigment particles will reduce the fiber and fiber combined with the relative size and hydrogen bonding forces, leading to a decline in paper strength. Meanwhile, the coating pigment particles will affect the strength of coated paper and coated paper coating performance. The common clay particles by the modification, synthesis of pigments using the new paper-silica Coated Composite-particles of Clay, analyzed the performance of the base paper and coated paper properties. The main contents include the following:Sol-gel method, using experimental design method for the synthesis DOE wrapped clay nano-silica composite particles. Screened by Plackett-Burman experimental design, preliminary screening of synthetic silica/clay composite particles significant factors:sodium, ammonia, temperature and speed. And through full factorial experiment to determine the impact of silica/ clay composite particles and the surface strength retention of the key factors:sodium polyacrylate and temperature.Using scanning electron microscopy, transmission electron microscopy, infrared spectroscopy on silica/clay composite particles and determination, including the silica/clay composite particles on the surface morphology, surface properties, surface structure and properties. Through the application of experiments on recycling paint on the base paper properties; compared with the ordinary clay nano-silica composite particles of clay wrapped coating and coated paper properties.Study found that:by PB and the whole factorial screening experiments to determine the synthesis of nano-silica composite particles wrapped clay is sodium polyacrylate key factors and temperature. Established a mathematical model of critical synthesis:Ash Retention 0.397+0.888sodiumpolyacrylate+0.0144temperature-0.024sodiumpolyacrylate*temperature. Us e of statistical methods and sol-gel solution polymerization method, determine the TEOS, clay, ethanol, sodium, ammonia was synthesized silica/clay composite particles of the optimum conditions:sodium polyacrylate 0.8g, temperature 28℃, ammonia 6ml, TEOS 12ml, ethanol 110ml, time 3h, speed 350r/min.Silica/clay composite particles and ordinary compared to the unmodified clay, used in the original paper copy made in the paper can greatly improve the retention rate, and burst index, tensile index, decrease in surface strength and other. indicators of low; Paper can improve whiteness, opacity and gloss. Silica/clay composite particle size distribution was compared to the unmodified clay evenly, feature smaller particle size, surface area, also has good wetting properties.Use of nano-silica composite particles with the ordinary clay wrapped clay coating configuration compared to a small modification of clay particles, water retention is good, low-shear viscosity, which is suitable for storage and transportation coatings.After the coating modified clay coated paper to improve brightness, opacity, print gloss and IGT surface strength. But the ink absorbent is less than the unmodified clay.