Shin-Etsu Silicones of America, Inc., a US subsidiary of Shin-Etsu Chemical Co. Ltd. of Japan, recently introduced its eight-carbon silane coupling agents. New to the coatings, adhesives, and sealants industries, the KBM-1083 (olefinic functional) and KBM-4803 (epoxy functional) lines have eight carbons, creating more space between the reactive ends of the silanes.  Typical silane coupling agents have three carbons separating the organic functional group from the inorganic silicon end. These traditional three-carbon spacer silanes create a tighter, more rigid network than their eight-carbon counterparts.  The result of this ‘greater space’ presents benefits that can be formulated into a wide variety of chemistries. These include: increased reactivity due to easier access to the reactive group; improved adhesion; and enhanced flexibility of the cured resin. Higher filler content is enabled, there is greater alkali resistance, and more compatibility with plastics. KBM-1083, which is olefinic functional, has a purity (GC percentage) 90 or higher, and viscosity (25C) of 1.8cSt. It enables higher filler contents, increases flexibility of cured resin, and increases alkali resistance and water resistance.  KBM-4803, which is epoxy functional, has a purity (GC percentage) 95 or higher, and viscosity (25C) of 6.6cSt. It increases adhesion and flexibility of cured resin, as well as alkali resistance and water resistance. It also enables higher filler contents.