A fully bio-based monomer derived from undecylenic acid, glycerol, and CO2 useful for the synthesis of polyhydroxyurethanes

Undecylenic acid, glycerol, and CO2 were used as building blocks for obtaining a fully bio-based carbonated monomer, useful for polyurethanes. The functionality of the monomer was close to 3 cyclic carbonates/mol, located in terminal positions. In a first stage, a synthetic triglyceride was obtained with 99% selectivity by esterification of glycerol and undecylenic acid at 160 degrees C. The triglyceride was then epoxidized using H2O2 and Amberlyst 15 or Amberlite IR-120 acidic exchange resins at 57 degrees C. The selectivity to epoxide was kept constant at 98% using Amberlite IR-120. Terminal cyclic carbonates were then inserted through epoxide moieties under mild conditions by the chemical fixation of CO2 at 80 degrees C and 6 MPa in 6 h. A complete conversion was obtained in 6 h reaction while the selectivity to carbonate groups was near to 99% during all the reaction time. An elastomeric polyhydroxyurethane was obtained by aminolysis of the carbonated monomer with ethylenediamine at 70 degrees C, affording a Young's modulus of 22.6 MPa and T-g of -15.2 degrees C. The material showed a good thermal stability below 240 degrees C.