A polymerizable acrylic composition according to claim 1 wherein said organoborane amine complex has the structure: ##STR12## wherein R6 is an alkyl group having 1 to 10 carbon atoms; R7 and R8 are independently selected from the group consisting of alkyl groups having 1 to 10 carbon atoms and phenyl-containing groups; the value of v is selected so as to provide a 0.5:1 to 4:1 ratio of primary or