Impact resistance of polyurethane elastomer enhanced by organic montmorillonite with interlayer anchored polymer chains

The development of materials with excellent impact resistance is essential for safety protection. Polyurethane elastomer (PUE) is widely used in impact protection; however, it has low dynamic compressive strength and poor energy absorption efficiency under high-speed impact, limiting its in-depth application in the protection field. Herein, an organic montmorillonite (MMT) with interlayer anchored polymer chains, named M@NH₃⁺, was synthesized via the dual modification of MMT involving surface grafting and cation intercalation by macromolecular amino silane, which was used to enhance the impact resistance of PUE. Based on the uniform dispersion of M@NH₃⁺ within the PUE matrix, the strong bonding at the polymer-filler interface and the synergistic action between M@NH₃⁺ lamellae, PUE-M@NH₃⁺ composite exhibited excellent mechanical properties and energy absorption capacity. Compared with pure PUE, the elastic modulus (+98.3%), static compressive strength (+37.0%), dynamic compressive strength (+35.4%) and impact energy absorption (+50.8%) of PUE-2wt%M@NH₃⁺ were significantly improved, which shows that it has potential applications in the field of high-speed impact protection. Highlights: Organic MMT with interlayer anchored polymer chains was prepared. The large interlayer spacing of M@NH₃⁺ facilitates its dispersion within the matrix. The interconnected M@NH₃⁺ lamellae can collaboratively disperse impact stress. The impact energy absorption of PUE composite has been remarkably improved.