Facile preparation and tunable light shielding properties of the mechanical enhanced thermosetting polyurethanes

Thermosetting polyurethanes (PUs) with the enhanced mechanical properties were facilely prepared without the catalysts by a simple two-step method. With the introduction of Phenylenediamine (PDA), the increasing visible-light transmittance for thermosetting PUs was observed and outstanding UV shielding properties were confirmed by TiO2 photocatalytic degradation of Rhodamine B. Moreover, the light-extended shielding behaviors in UV–vis region for thermosetting PUs were achieved by regulating the chain extenders of Benzidine (BDI), which were demonstrated by the compared experiments of TiO2 photocatalytic degradation of Rhodamine B protected by PU@BDI films. In addition, the repeatable mechanical behaviors for PUs were also obtained owing to the reconstruction of molecular crosslinking networks of PUs by the exchange of the urethane-urea covalent bond. Finally, we can conclude that thermosetting PUs provided with the enhanced mechanical properties and the promising applications in tunable UV–vis shielding.