The invention is a two part polymerizable composition comprising in one part an organoboron compound capable of forming free radical generating species amine complex and in the second part one or more compounds capable of free radical polymerization and a cure accelerator comprising a) at least one compound containing a quinone structure or b) at least one compound containing at least one aromatic ring and one or more, preferably two substituents on the aromatic ring selected from hydroxyl, ether and both, where there are two substituents they are located either ortho or para with respect to one another and a peroxide containing compound. The second part may further contain an agent capable of causing the organoboron compound to form free radical generating species upon contacting the two parts. The first part may further comprises one or more compounds capable of free radical polymerization. This facilitates formulating compositions that have commercially desirable volumetric ratios of the two parts. Adhesive compositions of the present formulation provide excellent adhesion to low surface energy substrates, such as plastics.