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Direct Functionalization of Polyisobutylene by Living Initiation with alpha-Methylstyrene Epoxide

Domenii publicaţii > Chimie + Tipuri publicaţii > Articol în revistã ştiinţificã

Autori: Song, J; Bódis, J ; Puskas, JE

Editorial: Wiley Periodicals, J. Polym. Sci., Polym. Chem., 40(8), p.1005-1015, 2002.

Rezumat:

This article describes the synthesis and characterization of
polyisobutylene (PIB) carrying one primary hydroxyl head group and a tertiary
chloride end group, [Ph-C(CH3)(CH2OH)-PIB-CH2-C(CH3)2Cl] prepared with direct
functionalization via initiation. The polymerization of isobutylene was initiated with
the alpha-methylstyrene epoxide/titanium tetrachloride system. Living conditions
were obtained from -75 to -50 degreesC (198-223 K). Low molecular weight
samples (number-average molecular weight similar to 4000 g/mol) were prepared
under suitable conditions and characterized by Fourier transform infrared and H-1
NMR spectroscopy. The presence of primary hydroxyl head groups in PlB was verified
by both methods. Quantitative Fourier transform infrared with 2-phenyl-1-propanol
calibration and H-1 NMR performed on both the hydroxyl-functionalized PIB and its
reaction product with trimethylchlorosilane showed that each polymer chain carried
one primary hydroxyl head group. The synthetic methodology presented here is an
effective and simple route for the direct functionalization of PIB.

Cuvinte cheie: living polymerization, functionalization of polymers, structure, carbocationic polymerization of isobutylene, primary hydroxyl-functionalized polyisobutylene,