Silane modified fillers for reinforcing polymers

Some white natural fillers (kaolin and talc) and synthetic mineral ones (precipitated silica, sodium-aluminium silicate, zinc silicate, calcium silicate) together with waste materials (cement dusts and post-fluor silicas) were subjected to surface modification and characterised. Various types of silane coupling agents (amino-, mercapto-, methacryloxy- and ureidosilanes) were used for surface modification. The modified fillers were mixed with butadiene-styrene rubber, polyurethane and PVC. Good physico-mechanical properties were obtained for PVC containing talcs and kaolins modified with methacryloxy- and ureidosilanes. The strength of polyurethanes was increased most by modification of the fillers with mercapto- and aminosilanes.