Abstract: Emulsions comprising a water insoluble or semi-soluble silane or mixtures of such silanes have been found useful when used alone or formulated into aqueous primer systems to improve the adhesion of sealants, adhesives or coatings to a variety of substrates. These aqueous primers are suitable for both inorganic and organic substrates having either porous or non-porous surfaces. In many cases they have been found to outperform solvent based primers. Primers of this type can be used with a variety of waterborne or solvent based sealants, adhesives or coatings including acrylic or polyurethane latexes, high solid polyurethanes, epoxies and silicones. When used with waterborne systems, it is not necessary to wait for the primer to dry before application of the sealant, adhesive or coating.

Abstract: Certain members of the class of N-silylalkyl-aspartic acid esters, when used to endcap polyurethane polymers, offer moisture curable, one-part sealant formulations having significantly improved physical property improvements over other members of the same class of organofunctional silanes. More specifically, polyurethane polymers terminated with either the dibutyl or diethyl maleate/primary aminoalkyl silane addition product offer sealants which substantially outperform comparative sealants obtained using polymers endcapped with other olefinic carboxylate ester (dimethyl maleate, dimethyl crotonate) or nitrile (acrylonitrile)/primary aminoalkyl silane addition products. Additionally, sealant formulations incorporating the dibutyl or diethyl maleate/primary aminoalkyl silane terminated polymers demonstrate unexpected improvements in both elongation and tensile strength performance. The dibutyl maleate and dimethyl maleate based polymers give significant increase in tear resistance.