S1 SUPPORTING INFORMATION LiCB 11 (CH 3 ) 12 Catalyzed Radical Polymerization of Isobutylene: Highly Branched Polyisobutylene and an Isobutylene - Ethyl Acrylate Copolymer Victoria Volkis, Hua Mei, Richard K. Shoemaker, and Josef Michl Department of Chemistry and Biochemistry, University of Colorado, Boulder, CO 80309-0215 TABLE OF CONTENTS List of abbreviations S2 Experimental S2 Selected polymerization data S4 Table 1. Dependence on Radical Initiator S4 Table 2. Polymerization of Liquid IB S4 Table 3. UV-Initiated Polymerizations S5 Table 4. Tests of Radical Mechanisms S5 Table 5. Tests of Radical Mechanisms S6 Table 6. Copolymerization of IB with Etyl Acrylate S6 Properties of Branched PIB S8 Figure 1. 1 H NMR of l-PIB (M w = 19,000 ) and b-PIB (M w = 4200) S8 Figure 2. DSC and TGA of b-PIB (M w = 4200) S8 Figure 3. GPC of b-PIB (left) and l-PIB (right) S9 Figure 4. 1 HDOSY NMR of b-PIB. S9 Figure 5. Gradient 1 HCOSY NMR of b-PIB. Vinylidene chain end S10 Figure 6. Gradient COSY NMR of b-PIB. iPr groups of branches S10 Figure 7. 2 H NMR of 1-d 6 S11 References S11