C-13 NMR CHEMICAL-SHIFTS OF POLYISOBUTYLENE END GROUPS AND RELATED MODEL COMPOUNDS

The detailed end-structures of CH3-,-Cl, exo-olefin, endoolefin, and-OH ended polyisobutylenes (PIB) have been characterized by high resolution13C NMR spectroscopy. Specifically, the13C chemical shifts characteristic of the various carbons in the following structures have been determined: ≈CH2C(CH3)2-CH2C(CH3)3, ≈CH2C(CH3)2CH2C(CH3)2Cl, ≈CH2C(CH3)2CH2C(CH3)=CH2, ≈CH2C(CH3)2CH=C(CH3)2, and ≈CH2C(CH3)2CH2CH(CH3)CH2OH. The structure analysis of model compounds was of utmost help in these investigations. The above information is of great value for the identification of terminally functional PIBs and analysis of reaction mixtures. © 1990 Springer-Verlag.