Abstract
We have prepared poly(styrene sulfone)'s containing 57 to 86 mol % styrene by free-radical copolymerization of styrene with sulfur dioxide at temperatures from 0 to 60 °C. The 13C spectra of these copolymers are reported for the first time, and the multiple resonances observed for the methine, methylene, and quaternary carbons are assigned to monomer triad sequences. These spectra allow an accurate determination of the monomer sequence distribution, which shows that 1:1 alternating sequences are not formed above about 40 °C. Poly(styrene sulfone)'s prepared above this temperature have variable-length styrene sequences, containing a minimum of two styrene units. Those prepared near room temperature have a highly regular monomer sequence distribution, with a macroscopic compositional average of two styrene units for every sulfur dioxide unit. These results cannot be explained by a simple first-order Markov copolymerization mechanism, and an alternative mechanism involving depropagation reactions is proposed.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
