A high-strength self-healing polyurethane elastomer incorporating superhydrophobicity

Abstract

Self-healing materials have always suffered from the difficulty of maintaining a balance between mechanical strength and self-healing efficiency. After many years of research, although there are researches on self-healing materials with high strength, most of them need to impose some external conditions or carry out self-healing for a long time. Therefore, balancing the mechanical properties and self-healing efficiency is still the focus of current research on self-healing materials. In this study, two different chain extenders were selected to successfully synthesize a polyurethane elastomer , PUGI-D3B2, which possesses high mechanical strength and outstanding self-healing properties. The introduction of the two extenders not only brought many different types of hydrogen bonds to the polyurethane molecular chain, but also provided more hydrogen bonding reorganization, thus forming more different types of hydrogen bonds. The mechanical strength of PUGI-D3B2 is as high as 15.34 MPa, and its surface scratches can completely disappear after self-healing at 60 °C for 10 h. After 12 h of repair, the degree of recovery of its mechanical strength is as high as 98.02%. Combined with the excellent self-healing properties of PUGI-D3B2, we prepared a multifunctional superhydrophobic material (SHN-SiO2/PUGI-D3B2), which provides a brand new idea for the future direction of multifunctional materials.

Keywords: hydrogen bonding, high mechanical strength, self-healing polyurethane elastomer, hydrophobic coating.