Abstract
Nitroxide-mediated radical polymerizations (NMP) of styrene at 100 °C using the cationic emulsifier tetradecyltrimethylammonium bromide (TTAB) have been carried out employing 2,2′-azoisobutyronitrile (AIBN) and two nitroxides of different water solubilities. The polymerization rate was lower and the molecular weight distribution more narrow in microemulsion than bulk at low conversion. The results can be rationalized based on the lower initiator efficiency in microemulsion than bulk, presumably caused by the confined space effect (compartmentalization) on geminate termination of AIBN radicals, and possibly also the confined space effect causing an increase in deactivation rate. The extent of retardation relative to bulk was more severe for the less water-soluble 2,2,5-trimethyl-4-phenyl-3-azahexane-3-oxy (TIPNO) than the more water-soluble N-tert-butyl-N-[1-diethylphosphono-(2,2-dimethylpropyl)] nitroxide (SG1) as expected based on more extensive nitroxide exit occurring in the case of SG1 than TIPNO. The...
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: 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.