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The Living ROMP of trans-Cyclooctene.

ABSTRACT: The living ring-opening metathesis polymerization (ROMP) of trans-cyclooctene (tCO) was investigated. ROMP of tCO in the presence of PPh(3) in THF leads to the formation of narrowly dispersed polycyclooctene (PCO). The presence of PPh(3) as an additive and the use of THF as a solvent were demonstrated to be necessary to suppress competing secondary metathesis processes in the ROMP of tCO. Under optimal conditions, narrowly dispersed PCO was achieved without high molecular weight contaminates. The PCO was then hydrogenated to form linear, narrowly dispersed polyethylene with a melting temperature of 139 °C. Protected, hydroxy-functionalized tCO was polymerized by this method to afford narrowly dispersed, hydroxylated PCO. Block copolymers containing polynorbornene and PCO or containing differentially functionalized PCO were also synthesized and hydrogenated to form block copolymers containing blocks of linear, narrowly dispersed polyethylene.

SUBMITTER: Walker R

PROVIDER: S-EPMC2850575 | biostudies-literature | 2009 Feb

REPOSITORIES: biostudies-literature

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The Living ROMP of trans-Cyclooctene.

Walker Ron R Conrad Rosemary M RM Grubbs Robert H RH

Macromolecules 20090201 3

The living ring-opening metathesis polymerization (ROMP) of trans-cyclooctene (tCO) was investigated. ROMP of tCO in the presence of PPh(3) in THF leads to the formation of narrowly dispersed polycyclooctene (PCO). The presence of PPh(3) as an additive and the use of THF as a solvent were demonstrated to be necessary to suppress competing secondary metathesis processes in the ROMP of tCO. Under optimal conditions, narrowly dispersed PCO was achieved without high molecular weight contaminates. Th ...[more]

PMID: 20379393

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