Acryloyloxypropylalkoxysilane compositions containing one or more acryloyloxypropylalkoxysilanes of the formula ##STR1## wherein R.sup.1 and R.sup.2 are, independently, identical or different alkyl groups having 1 to 4 carbon atoms, m is an integer from 0 to 2 and R is hydrogen or a methyl group, and an amount of one or more tertiary amines sufficient to provide a pH higher than the intrinsic pH of the acryloyloxypropylalkoxysilane itself and to improve shelf storage, a process for their preparation, and to their use in preparing silicon-containing coating materials and paints.