Abstract: | The copolymerization of acrylic monomers (M) [acrolein (AL), methyl acrylate (MA), acrylamide (AM) and acrylonitrile (AN)] with liquid sulfur dioxide (S) at low temperature and high dilution in the presence of tert-butyl hydroperoxide gives high SO2 incorporation into the resulting copolymers. Analysis of the composition of these polysulfones, by elemental analyses and 13C NMR, shows that they consist mostly of the MMM, SMM, MMS and MSM triad monomer sequences. Thermal (TG) analyses of selected samples demonstrate that their thermal stability, up to 30% weight loss, increases for different acrylic comonomers as follows: AL < AM < MA < AN. Preliminary flammability tests revealed that flame retardancy increases with increasing SO2 content in the copolymer. |