The Graft-Polymerization of Poly(Ethylene Glycol) Phenyl Ether Acrylate onto Polyurethane and Its Impact on the Mechanical Properties and Chain Packing

The poly(ethylene glycol) phenyl ether acrylate (PEPA) monomers are graft-polymerized onto polyurethane (PU), and its impacts on water compatibility, chain packing, tensile stress, and shape recovery capability are evaluated. The grafted poly(PEPA)s slightly increase the degree of cross-linking due to the linking between themselves. The water compatibility (water contact angle, water swelling, and water vapor permeation) are affected slightly by the grafted poly(PEPA). The grafted poly(PEPA) does not notably influence the melting of soft segments, but the crystallization of soft segments is reduced significantly. The grafted poly(PEPA) does not significantly affect the glass transition of soft segments. The grafted poly(PEPA) notably increases the breaking tensile stress with the increase in PEPA content, but the breaking tensile strain decreases slowly with increasing PEPA content. The grafted poly(PEPA) rapidly improves the shape recovery capability of PU and slowly decreases the shape retention capability with the increase in PEPA content. Therefore, the grafted poly(PEPA) slightly modifies the water compatibility but notably enhances the breaking tensile stress and shape recovery capability of PU.