STUDIES ON THE VINYL POLYMERIZATION PHOTOINITIATED BY PARA-BENZOYLPEROXYBENZOIC ACID TERT-BUTYLESTER

Data are presented which demonstrate that p-benzoylperoxybenzoic acid tert-butylester (BPE) undergoes an efficient photodecomposition producing cleavage of the peroxy bond. The excited triplet benzophenone carbonyl group of the perester is quenched by vinyl monomers (the degree of which depends on the type of monomer used) thus reducing the rate of decomposition of BPE when it is used as a photoinitiator. Radicals generated from the decomposition of BPE are highly efficient in initiating vinyl polymerization. The benzophenone-containing end groups of the polymer chain can be estimated and the carbonyl function is useful for polymer modification.