Construction of Reinforcing and Toughening Silicon Hybrid Polyurethane Elastomers With Thermo-Optic Response via the Strategy of Combining Toughness With Softness

In this work, the reinforcing and toughening silicon hybrid polyurethanes (SPUs-diol) were achieved by strategically incorporating rigid silicon groups and flexible diol molecules into the polyurethane skeleton. As a result, introducing the types or proportions of diols in PU segments effectively regulated the segment characteristics and hydrogen bonds, resulting in unusual microstructural evolution. Furthermore, a synergistic enhancement in mechanical properties was found, where the maximum tensile strength and elongation at break reached 20.28 ± 1.99 MPa and 225.15% ± 35.57%, respectively, several times greater than those of SPUs with low contents or short chains of diols. Simultaneously, SPUs-diol showed different thermo-optic responses due to the dissociation and recombination of hydrogen bonding. In particular, the higher contents or longer chains of the diols were, the more significant thermo-optic response SPUs-diol showed. In sum, this study was a new view for the innovation and development of PU-based materials. Highlights Silicon-hybrid polyurethanes with enhanced mechanics were constructed. SPUs-diol provided high reinforcing and toughening properties. SPUs-diol showed the unusual evolution of microphase separation. Thermo-stimuli responsive effect was adjustable effectively.