Bis-Ethylhexyl Poly(Caprolactone/Pentaerythritol)/IPDI Copolymer Succinate is a urethane copolymer made by a two-step synthesis. First, a polyester made by polymerizing Epsilon-Caprolactone with Pentaerythritol is reacted with Isophorone Diisocyanate. 2-ethyl hexanol is used as an end-capper for the urethane copolymer. In the second step, the urethane copolymer is esterified with succinic anhydride.