Synthesis and Characterization of Unsaturated Poly(ester-urethane) as Self-Healing Structural Adhesive

This study focused on developing structural adhesives with self-healing capability while reducing theuse of toxic isocyanates. To achieve this, an unsaturated poly(ester-urethane) (PEBU) wassynthesized using a urethane diol obtained via a non-isocyanate route. PEBU was functionalized withfurfuryl alcohol (FA) through a Diels-Alder reaction. The resulting material, fPEBU, was cured withan isocyanate crosslinker (PM۲۰۰) to produce polyurethane structural adhesive. The self-healing andadhesion properties of the prepared compound were investigated, and the results were compared withthe same type of FA-functionalized unsaturated polyester containing no urethane residue (fPEB).Both of these polymers exhibited a very good ability to heal cracks induced on their surface throughmild warming of the adhesive and the occurrence of a Retro-Diels-Alder reaction. The adhesivesprepared from fPEBU showed a ۵۰% improvement in adhesion strength compared to the otheradhesive made from fPEB, which contains no urethane bonds in the backbone.

کلیدواژه ها:

Adhesives ، Poly(ester urethane) ، Diels Alder reaction ، Nonisocyanate route ، Self-Healing Networks.