High-strength millable polydimethylsiloxane-based polyurethane elastomers with a broader application temperature range

Abstract

Silicone elastomers exhibit superior cold and heat resistant properties compared to all other elastomers, and are widely used in aerospace, electronic appliances and other fields. However, they are prone to crystallization and even become brittle at temperatures below −50 °C, thereby diminishing their cold resistance performance. Besides, the low mechanical strength of the silicone elastomer is also a fatal defect, restricting its broader application. Herein, we design and synthesize millable polydimethylsiloxane-based polyurethane elastomers (MPUs), possessing an extensively broadened range of application temperatures spanning from −116 to 275 °C. Surprisingly, the tensile strength of MPUs can reach as high as 30.97 MPa at −60 °C, with an elongation at break of 233%, demonstrating a remarkable improvement in comparison to the existing silicone elastomer. Additionally, the tensile strength is 11.98 MPa at room temperature, which corresponds to a 20% increment relative to the traditional silicone elastomer. Furthermore, it also exhibits excellent properties such as hydrophobicity, non-cytotoxicity, and fluorescence. Thus, the MPUs possess extensive prospective applications.