Synthesis of Biobased Long-Chain Polyesters by Acyclic Diene Metathesis Polymerization and Tandem Hydrogenation and Depolymerization with Ethylene

[Image: see text] Acyclic diene metathesis (ADMET) polymerization of biobased α,ω-dienes of bis(undec-10-enoate) with diols (1,4-butanediol, isosorbide, isomannide, and 1,4-cyclohexanedimethanol) afforded high-molecular weight unsaturated polyesters, and subsequent tandem hydrogenation (H(2) 1.0 MPa, 50 °C, 3 h) gave the saturated polymers upon addition of a small amount of Al(2)O(3) (1.0–1.7 wt %). Subsequent reaction of the unsaturated polymers with ethylene afforded the oligomers (by depolymerization and degradation).