An organosilicon compound having its unit formula selected from: ##STR3## wherein R1 is a monovalent hydrocarbon group having from 1 to 10 carbon atoms and free of aliphatic unsaturation, R2 is an alkylene group having from 2 to 10 carbon atoms, m has value of greater than zero, a has a value of greater than zero, b has a value of greater than zero, c has value of greater than zero, and d has valu