Premium
Anionic Polymerization of Cyclohexa‐1,3‐diene in Cyclohexane with High Stereoregularity and the Formation of Crystalline Poly(cyclohexa‐1,3‐diene)
Author(s) -
Quirk Roderic P.,
You Fengxiang,
Zhu Lei,
Cheng Stephen Z. D.
Publication year - 2003
Publication title -
macromolecular chemistry and physics
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.57
H-Index - 112
eISSN - 1521-3935
pISSN - 1022-1352
DOI - 10.1002/macp.200390048
Subject(s) - cyclohexane , dabco , chemistry , octane , diene , differential scanning calorimetry , polymer chemistry , polymerization , benzene , nuclear magnetic resonance spectroscopy , organic chemistry , polymer , natural rubber , physics , thermodynamics
Polymerization of cyclohexa‐1,3‐diene using sec ‐BuLi as initiator in cyclohexane produces both soluble (70–90 wt.‐%) and insoluble (10–30 wt.‐%) fractions depending on the temperature. The insoluble poly(cyclohexa‐1,3‐diene) was crystalline as determined by X‐ray diffraction and differential scanning calorimetry analysis ( T m = 178 °C). Both fractions were characterized by size exclusion chromatography and by 1 H NMR and 13 C NMR spectroscopy. The microstructures of both fractions were determined by high‐resolution 1 H NMR and quantitative 13 C NMR spectroscopy and compared to those poly(cyclohexa‐1,3‐diene)s prepared in benzene and in cyclohexane with 1,4‐diazobicyclo[2.2.2]octane (DABCO) as additive. The amount of 1,4‐addition of the insoluble fraction in cyclohexane was ≥ 97% and the cis planomer content was higher in cyclohexane than in benzene or in cyclohexane with DABCO as additive.DSC traces for the insoluble PCHD recrystallized from dichloroethane.