Bis-HEMA Poly(Caprolactone Neopentyl Glycol)/1,4 Butanediol/ IPDI Copolymer is a urethane polymer formed by a multi-step process. First, a polyester is made by reacting Epsilon-Caprolactone with Neopentyl Glycol, which is subsequently reacted with 1,4-Butanediol and Isophorone Diisocyanate. The resulting polymer is end-capped with HEMA