Optimization of microencapsulation of silane coupling agent by spray drying using response surface methodology

A microcapsule containing a silane coupling agent was prepared by spray drying. The optimal encapsulating condition was determined by employing a response surface methodology with a central composite design. The effect of emulsion’s solid content and oil concentration, inlet air temperature, and atomizer speed on properties of microcapsule were investigated. The resulting microcapsule containing silane coupling agent and possessing an unbroken surface and a good shape under optimized conditions exhibited an encapsulation efficiency of 82.7%, average size of 21.3?µm, and moisture content of 0.93%. The experimental results agree well with the model prediction, with a relative error below 5.0%.