• Letourneau, Jeanjacques
• Fages, Jacques
• Dave, Rajesh
• Wei, Dongguang
• Wang, Yulu
• Sauceau, Martial
• Pfeffer, Robert

Abstract

International audience ; A modified RESS process for particle coating with a solution of polymer in supercritical CO2 was studied in this research. This technique involves extracting the polymer with supercritical CO2, with or without a cosolvent in an extraction vessel, and then precipitating the polymer onto the surface of host particles in a second precipitation vessel by adjusting the pressure and temperature inside the precipitator to lower its solubility. The research was performed using a pilot‐scale supercritical apparatus, glass beads as host particles and two different polymers as coating materials. Experiments showed that the coating of glass beads with polyvinyl chloride‐co‐vinyl acetate (PVCVA) and hydroxypropyl cellulose (HPC) was successfully achieved. Scanning electron microscopy (SEM), energy dispersive X‐ray spectrometry (EDS), energy dispersive X‐ray mapping and thermogravimetric analysis (TGA) were used to characterize the coatings obtained. The results indicate that the process of particle coating with supercritical solution is a promising environmentally friendly, alternative coating method with little or no organic solvents required.

Topics

• impedance spectroscopy
• surface
• polymer
• scanning electron microscopy
• experiment
• extraction
• glass
• glass
• thermogravimetry
• precipitation
• Energy-dispersive X-ray spectroscopy
• cellulose
• spectrometry
• coating method