Preparation and Properties of Acrylic Acid-Modified Multicross-Linked Two-Component Waterborne Phase-Change Polyurethane

Phase change materials (PCMs) are broadly adopted in buildings and other applications because of their excellent energy storage effect. However, aqueous phase change materials are less reported. In this article, a waterborne polyurethane with phase change functionality (WPU-A) was prepared and modified with trimethylolpropane (TMP) and hydroxyethyl methacrylate (HEMA); and then allowed to cross-link with a waterborne polyurethane (WPU-B) with PTMG as the soft segment to produce a multicross-linked, two-component phase-change waterborne polyurethane (PCMWPU). It is discussed that the phase change properties, hydrophobicity, and tensile strength of PCMWPU films were improved with the addition of WPU-A. The data show that the highest enthalpy of PCMWPU films can reach 90.3 J/g, the static water contact angle can reach 108.3°, and the highest tensile strength is 27.4 MPa. In addition, PCMWPU film has shape stability at higher temperatures (100 °C), no liquid leakage, good thermal stability, and shows some reversible light transmission phenomenon, which has a wide range of application prospects.