A transparent, anti-blue-light, and high strength nylon/nickel phosphate oligomer nanocomposite formed via intermolecular hydrogen bond crosslinking

Polymer/transition metal inorganic salts nanocomposites are promising engineering materials in automotive, electronics, aerospace and smart wearables fields. However, the interfacial incompatibility always causes agglomeration and phase separation, constraining their further application. Inspired by inorganic oligomers' polymerization, nylon/nickel phosphate oligomer (NPO) nanocomposite (ENCC) was prepared via hydrogen bond crosslinking method. Due to the formation of hydrogen bonds between  PO 4 3− end groups of NPO with an average diameter of 6.5 ± 1.2 nm and  NH groups on the nylon molecular chain, the phase compatibility is greatly improved. Hence, NPO was uniformly nano-dispersed and had no obvious agglomerate in ENCC, inducing an invisible phase interface at nano-micro scale. Nylon/nickel phosphate oligomer showed an excellent reinforcing effect on nylon, the tensile strength and elongation of ENCC reached 28 ± 0.8 MPa and 585 ± 26% at a high loading of 20 wt%, increased by 155% and 92%, compared with pure matrix, respectively. Furthermore, ENCC was still optically transparent and had excellent anti-blue-light performance (up to 96.6%). Highlights Novel inorganic/nylon composite prepared by hydrogen bond crosslinking method. Phase separation and aggregation problems were solved remarkably. Inorganic metal phosphate dispersed with a diameter of 6.5 ± 1.2 nm. The composite was still transparent at 20 wt% loading of metal phosphate. Tensile strength and elongation increased by 155% and 92%, respectively.