Studies on copolymerization of N-isopropylacrylamide and glycidyl methacrylate

Free-radical homopolymerization of N-isopropyl acrylamide (NIPA, monomer 1) and copolymerizations of NIPA with glycidyl methacrylate (GMA, monomer 2) were conducted in deuterated dioxane at 70 degreesC. The conversion of the monomers was followed by H-1 NMR spectroscopy. After the polymerization rea ctions the polymers were precipitated and analyzed. Reactivity ratios were determined using both Fineman-Ross and extended Kelen-Tudos methods. Values obtained by these two methods were r(1) = 0.39, r(2) = 2.69 and r(1) = 0.3 0, r(2) = 2.66, respectively. In both cases, r(1r2) similar to 1, which is indicative of an ideal copolymerization resulting in a first-order Markov d istribution of the monomers in the final copolymer. The compositional heter ogeneities of the polymers were estimated by following the instantaneous co polymer compositions as functions of conversion. Given the different reacti vities of the two monomers it is concluded that a copolymer with a homogene ous distribution of monomers may be obtained not by a batch reaction, but b y slowly and continuously adding GAIA into the polymerizing reaction mixtur e. (C) 2001 John Wiley & Sons, Inc.