Renewable (semi)aromatic polyesters from symmetrical vanillin-based dimers

Two symmetrical biphenyl monomers derived from vanillin, a methylated divanillyl diol and a methylated dimethylvanillate dimer, were synthesized and employed as (co)monomers for the design of renewable (semi)aromatic polyesters. The reactivity in polytransesterification of these new monomers was investigated in bulk in the presence of various catalysts. The polytransesterification between methylated divanillyl diol and a series of bio-based diesters having different chemical structures led to amorphous thermoplastic polyesters with glass transition temperatures ranging from -5 to 139 degrees C and thermal stability up to 350 degrees C.