Transparent, flame‐retarded, self‐healable, mechanically strong polyurethane elastomers: Enabled by the synthesis of phosphorus/nitrogen‐containing oxime chain‐extender

Abstract Polyurethane (PU) elastomer has been widely used due to its excellent mechanics, acid and alkali resistance, abrasion resistance, and other properties. However, obtaining simultaneous mechanically strong, flame‐retarded, transparent, and efficient self‐heal ability of PU elastomer is of great challenge due to the structural design. Here, a phosphorus/nitrogen‐containing Oxime chain extender (PSK‐2) was introduced into the synthesis of PU elastomers to obtain a transparent, flame‐retarded, self‐healable, mechanically strong PU elastomers. The PU elastomers exhibited high tensile strength of ~23.3 MPa, breaking strain of ~1693%, good flame retardancy with high LOI of ~29.2%, and UL‐94 V1 rating with the addition of 4.67 mmol (mass fraction 1.37 wt%) PSK2. Furthermore, the PUPSK2 elastomer material also had good healing ability up to 60% at room temperature and good transparency of 83.7% at 350–800 nm visible.