Divergent Catalytic Strategies for the Cis/Trans Stereoselective Ring-Opening Polymerization of a Dual Cyclic Carbonate/Olefin Monomer.

ABSTRACT: A dual seven-membered cyclic carbonate/olefin monomer was synthesized from CO₂ and cis-1,4-butenediol and polymerized. The properties of the polymer were controlled using divergent catalytic strategies toward the stereochemistry of the olefin. Ring-opening polymerization of the cyclic carbonate using an organocatalytic approach retained the cis-stereoconfiguration of the olefin and yielded a hard semicrystalline polymer (T_m 115 °C). Ring-opening metathesis polymerization using Grubbs' catalyst proceeded with high trans-stereoregularity (95%) and produced a soft amorphous polymer (T_g -22 °C). Cis to trans isomerization of the polymer was possible using Cu(I) salts under UV light. In all polymers, the C?C double bond remained available for postpolymerization modification and thermoset resins were formed by cross-linking. From this single monomer, cis-trans-cis triblock copolymers, with potential applications as thermoplastic elastomers, were synthesized by combining both strategies using cis-1,4-butenediol as a chain transfer agent.

SUBMITTER: McGuire TM 

PROVIDER: S-EPMC7007229 | biostudies-literature | 2019 Aug

REPOSITORIES: biostudies-literature