The present invention relates to asymmetrical siloxy compounds of the formula ##STR1## wherein R.sup.1, R.sup.2 and R.sup.3 are independently selected from the group consisting of alkoxy radicals having from 1 to 8 carbon atoms; R.sup.4 is selected from the group consisting of alkylene groups having from 1 to 15 carbon atoms and arylene and alkyl-substituted arylene groups having from 6 to 10 carbon atoms; n is an integer of from 2 to 8 and X is selected from the group consisting of ##STR2## and R.sup.5 is selected from the group consisting of alkyl groups having from 1 to 15 carbon atoms, aryl and alkyl substituted aryl groups having 6 to 10 carbon atoms.