Studies of atom transfer radical polymerization (ATRP) of acrylates by MALDI TOF mass spectrometry

Atom transfer radical polymerization (ATRP) of methyl, butyl and tert-butyl acrylates was studied at conditions when low molecular weight polymers (M- n congruent to 2 . 10(3)) are formed, i.e., at relatively high concentratio n of initiator (ethyl 2-bromopropionate) and catalyst (CuBr/amine). MALDI T OP analysis of the polymer samples isolated at different stages of polymeri zation revealed that in the course of polymerization potentially active mac romolecules gradually converted into inactive macromolecules devoid of term inal bromine. a possible transfer mechanism, involving amine is a component of the catalytic system is proposed. It was shown that quantitative analys is of the MALDI TOF spectra allows one to estimate the ratio of apparent ra te constants of propagation and degradative transfer, providing quantitativ e information to what-extent the system conforms to the controlled polymeri zation scheme.