C. Bielawski, O. Scherman, R. Grubbs
May 1, 2001
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0
Influential Citations
57
Citations
Journal
Polymer
Abstract
Abstract Bis(acetoxy)-terminated telechelic poly(butadiene) (PBD) with molecular weights controllable up to 3.0×10 4 have been prepared via the ring-opening metathesis polymerization (ROMP) of cyclooctadiene when 1,4-bis(acetoxy)-2-butene was included as a chain transfer agent (CTA). The polymerizations were catalyzed by a highly active ruthenium catalyst 1,3-bis(2,4,6-trimethylphenyl)imidazol-2-ylidene) (PCp 3 )(Cl 2 Ru=CHCHC(CH 3 ) 2 (Cp=cyclopentyl) ( 6 ) with monomer/catalyst ratios as high as 9.8×10 4 . Removal of the acetoxy groups with sodium hydroxide afforded hydroxy end-terminated telechelic PBD (HTPBD). Examination of the telechelic PBDs revealed an exclusive 1,4-PBD microstructure with a predominately trans geometry (up to 90%). The high activity and stability of 6 permitted a one-step synthesis of HTPBD using the unprotected free alcohol, 2-butene-1,4-diol, as the CTA.