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Near‐infrared (NIR) light responsive shape memory polymers (SMPs) can realize remotely and regionally controlled shape changing that shows broad potential applications. Herein, an NIR‐responsive shape memory polymer (G/PNs) is prepared by introducing reduced graphene oxide to liquid crystal elastomers‐based polymer networks (PNs). The G/PNs present regulated reversible stress by tuning the NIR light irradiation. Furthermore, since the G/PNs are 3D‐printed with designed structure, the deformed 3D printing structure can be regionally patterned with varied shapes by controlling the moving path of NIR laser. In addition, the stress relaxation and cyclic stress–strain measurements are further studied to reveal the energy loss during the deformation and shape memory cycles. In compare with the previous work, the SMP networks provide a rather high reversible actuation stress and can realize remotely control by NIR. The NIR‐encoded shape memory effect can be used as actuators, artificial muscles. [ABSTRACT FROM AUTHOR]

[Display omitted] • A biomimetic strategy to prepare supramolecular polyurethanes (SPUs) was described. • The polymer networks were significantly enhanced by H-bonds and coordination bonds. • SPUs showed ultrahigh modulus (146.92 MPa) and excellent self-healing (95%, 24 h). • A bilayer polymer film was designed to realize fast self-healing at room temperature. Developing a new generation of polymeric materials that integrate robust mechanical properties with ultra-high self-healing efficiency at ambient temperature remains a formidable challenge due to the proverbial trade-offs among strength, toughness, and self-healing ability. Herein, inspired by biological systems (titin protein molecular structure and Nereis jaws), a series of updated supramolecular polyurethanes have been successfully synthesized by incorporating hierarchical hydrogen-bonding motifs into the polymer matrix and subsequently coordinated with Zn2+ ions. Relying on collaborative reinforcement of optimized hierarchical hydrogen bonds and metal-ligand coordination bonds, the resulted supramolecular elastomers exhibited a robust strength of ∼14.15 MPa, an excellent toughness of ∼47.57 MJ m−3, and Young's modulus of ∼146.92 MPa. Benefiting from the rational design of hard domains, high mobility of chains, and the synergistic effect of multiple non-covalent interactions, the mechanical properties are far superior to the previously reported room‐temperature self‐healing materials. In addition, with the structural design of "inner soft and external hard" model, we also fabricated a bilayer polymer film with a gradient distribution that can achieve rapid self-healing, with an unexpectedly high self-healing efficiency of 95% at ambient temperature in 24 h. This work opens up a new avenue for fabricating room-temperature self-healing materials with robust mechanical strength and toughness at the same time. [ABSTRACT FROM AUTHOR]

• Hyperbranched polyurethane was applied through grafting epoxy resin to obtain interpenetrating polymer networks. • Crosslinking network points help enhancing thermal and mechanical properties. • All interpenetrating polymer networks express excellent shape memory effect. In this article, a type of hyperbranched polyurethane (HBPU) with triazine structure was successfully synthesized. Afterwards, HBPU was applied through grafting epoxy resin (EP) to fabricate the interpenetrating polymer networks (IPNs) with different ratio of HBPU/EP. The structure of HBPU prepolymer and the formation of the HBPU/EP IPNs were characterized and confirmed by Nuclear Magnetic Resonance (NMR) and Fourier Transform Infrared (FTIR) spectroscopy, and the nanoscale phase separation in IPNs composite was analyzed by Atomic Force Microscope (AFM). Besides, the thermal and mechanical results indicated that the IPNs structure enables the material with high strength and thermal stability. Shape memory cycles test demonstrated that the HBPU/EP INPs possess an excellent shape memory performance, and the best shape fixity and recovery were presented by IPNs composite with 20 wt% HBPU. [ABSTRACT FROM AUTHOR]