Monomer reactivities and kinetics in radical copolymerization of hydroxystyrene derivatives and tert-butyl (meth)acrylate

Monomer reactivity ratios in radical copolymerization of 4-hydroxystyrene d erivatives with tert-butyl acrylate and methacrylate have been determined b y nonlinear regression as well as by the Kelen-Tudos graphic method. The hy droxystyrene derivatives employed in the study included 4- and 3-hydroxysty renes, 4- and 3-acetoxystyrenes, and 4-tert-butoxycarbonyloxystyrene. The e lectron-rich 4-hydroxystyrene is unique as its copolymerization with the el ectron-deficient acrylate monomers is more alternating. The simulation of t he copolymerization on the basis of the reactivity ratios has been shown to fully describe the copolymerization behavior and copolymer structures. The kinetics of radical copolymerization of 4-acetoxystyrene with tert-butyl ( meth)acrylate has been studied in detail using a gas chromatographic proced ure and also by in situ H-1 NMR spectroscopy. The kinetics behavior has sho wn an excellent agreement with the computer simulation of the copolymerizat ion using the reactivity ratio values determined on the basis of the termin al model.