URETHANES AND POLYURETHANES BEARING FURAN MOIETIES .4. SYNTHESIS, KINETICS, AND CHARACTERIZATION OF LINEAR-POLYMERS

The synthesis and characterization of a novel family of linear polyurethanes is reported. The original feature stems from the use of furanic monomers, either as diols, or as diisocyanates or both. The kinetics of these systems followed the classical second-order behavior with rate constants which showed a marked influence of steric and electronic factors linked to the specific structures of both types of furanic monomers. All polyurethanes had regular structures and fairly high molecular masses, viz. around 10000. A careful analysis of their glass transition temperatures made it possible to establish clear-cut correlations as a function of the position and number of furan rings in the polymer repeat unit. Their thermal degradation gave rise to considerable amounts of carbonaceous residues, which was more, the higher the proportion of furan rings in the structure.