Cationic Polymerizations Polymer Synthesis CHEM 421 R R electron releasing group C ⑧ X⊙ R R,R'= -cH3一CH3☆Poly((isobutylene) -0-CH3 H 一 CH3 H 一 C2Hs H R H H Polymer Synthesis Cationic Polymerizations CHEM 421 C R R' X R = electron releasing group CH 3 CH 3 R, R’= CH 3 H H H H H O CH 3 C 2 H 5 R Poly(isobutylene)