High-strength bone polyurethane adhesive with rapid curing for bone tissue injury repair

Bone tissue adhesives have advantages such as preventing stress shielding and secondary surgical infections, fixing small bone fragments, easing operations, and enhancing wound adaptability. These methods can be applied for the traumatic repair of comminuted fractures. Currently, commercial tissue adhesives fail to meet the biological safety and mechanical strength requirements of bone tissue adhesives. To address this situation, we developed and screened a rapidly cured high-strength polyurethane bone adhesive. Research has shown that polyurethane bone adhesives have shorter curing times (236 s to 273 s), higher tensile moduli (425.88 MPa to 666.38 MPa), compressive moduli (214.67 MPa to 450.66 MPa), and adhesive strengths (0.92 MPa to 5.86 MPa). It can withstand cyclic stresses ranging from 0.01 MPa to 1 MPa for 1000 cycles. Polyurethane bone adhesive surpasses the inadequate adhesive performance and <i>in vivo</i> repair functionality of existing commercial bone cements, achieving effective repair of bone tissue injuries. Furthermore, we developed an unsaturated ester-modified secondary amine curing agent based on the Michael addition reaction, enabling rapid and safe curing of bone polyurethane adhesives and thereby providing a novel and effective repair solution for bone tissue injuries.