URETHANES AND POLYURETHANES FROM SUBERIN .1. KINETIC-STUDY

Within the context of a study on the preparation and the characterizat ion of polyurethanes based on suberin, as a polyol, and conventional p olyisocyanates, it was deemed necessary to carry out a preliminary stu dy on the reactivity of the hydroxy functions of suberin. Aliphatic an d aromatic mono- and di-isocyanates were tested and the kinetics of th is system followed the classical second order up to conversions of abo ut 85%. The influence of the steric hindrance and the electronic facto rs, linked to the specific structures of both types of isocyanates, wa s established. (C) 1997 Elsevier Science B.V.