AEROSOL AND SOLUTION MODIFICATION OF PARTICLE-POLYMER INTERFACES

In recent years several investigators have focused on the synthesis of uniformly and continuously coated particles to impart improved chemic al stability, mechanical strength, morphology and/or dispersibility to powders required for preparing next-generation composities. This pape r reviews two in situ reaction methods employed at Clarkson University to selectively coat individual particles having widely different shap e, size and chemical composition. The aerosol procedure allows core pa rticles to become coated using room temperature liquid-gas reactions. Alternatively, coating particles dispersed in a solvent containing rea ctive precursors is more applicable to industrial processing. Uniform, well-adhering coatings of polyurea on titania powder, of polydivinylb enzene on silica beads, and of carbon and boron nitride on silicon car bide whiskers were made by selecting the correct precursors and reacti on chemistries. Qualitative assessment of adhesion between the coating s and cores is given.