ADMET DEPOLYMERIZATION - SYNTHESIS OF PERFECTLY DIFUNCTIONAL (F=2.0) TELECHELIC POLYBUTADIENE OLIGOMERS

Diester, disilyl ether, and diimide telechelic 1,4-polybutadiene oligomers have been synthesized via acyclic diene metathesis (ADMET) depolymerization. Mass spectrometry, in combination with NMR spectroscopy and gel permeation chromatography, show that these telechelics are perfectly difunctional (f = 2.0). The mechanism yielding these telechelics is described, which illustrates that the chemistry first proceeds through intramolecular cyclization of 1,4-polybutadiene. These macrocyclic butadienes then cross metathesize with a functionalized monoene to form linear difunctional telechelic oligomers.