SYNTHESIS OF POLYMERS CONTAINING PSEUDOHALIDE GROUPS BY CATIONIC POLYMERIZATION .9. AZIDO END-CAPPED POLY(2-METHYLPROPENE) BY POLYMERIZATION INITIATED BY THE SYSTEM LEWIS-ACID 2-AZIDO-2-PHENYLPROPANE

The polymerization of 2-methylpropene in methylene dichloride can be i nitiated by 2-azido-2-phenylpropane (APP) in the presence of some Lewi s acids. The system APP-boron trichloride gave only the usual polymer functionalization by a tertiary chloride at one chain end and the cumy l moiety at the other end. The system APP-antimony pentafluoride gave no significant functionalization. The system APP-titanium tetrachlorid e gave a polymer which was partly functionalized by an azide group. Th e system APP-boron trifluoride gave complete functionalization within experimental accuracy. These experiments show that, by cationic polyme rization of 2-methylpropene and using the suitable initiator-Lewis aci d combination, it is possible to obtain by direct synthesis from the m onomer a polymer specificially functionalized by a carbon-to-nitrogen bond. Less specific functionalization is also possible in a nonpolar m edium.