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Renewable bamboo materials have broad application prospects in the fields of structural construction, insulation and acoustic management due to their multi-layer porous structure, attractive directional layout texture, ultra-fast growth rate, and excellent mechanical strength. However, the annual loss of bamboo material due to the microbial corrosion accounts for one-tenth of the total output. In this work, the hydrophobic associating hydrogel (HAH) with chitosan (CS) and zinc oxide (ZnO) has been in situ filled in the micro-nano-scale pores of natural bamboo materials to significantly enhance their anti-microbial fouling performance. It is difficult for the mildew and oxygen in the air to come into the bamboo materials due to the artificial hydrogel barrier layer. CS and ZnO nanomaterials further increase the anti-bacterial rate of bamboo composites to 100%. Based on the physical crosslinking between the polyacrylamide (PMA) of HAH hydrogel and natural bamboo fibers, CS and ZnO bacteriostatic media are not easy to be lost from the bamboo materials. The 100% anti-bacterial rate of the bamboo composite materials can be maintained for at least 56 days. Therefore, the bamboo composites have great application potential as building materials in the future. In-situ polymerization method was used to fill the micropores of bamboo with super-elastic hydrogel to enhance its anti-microbial fouling performance.

Bamboo, as a potential ecological building material, has attracted a lot of attention, due to its wide distribution, more than 1000 species, short growth cycle of 3–5 years, three times the carbon dioxide adsorption of other plants, and tensile strength comparable to steel or concrete. The major challenges of bamboo are the single color and poor anti-microbial corrosion, based on the intrinsic nature of polysaccharides such as cellulose. In this work, a novel bamboo composite material that exhibits a rich variety of colors (red wine, light yellow, coffee, white, black), excellent color retention, and anti-microbial corrosion for 14 days under a relative humidity of 60–95% is prepared by an easy-to-scale chemical grafting method. Oxidation treatment is the basic condition for bamboo to obtain bright colors, and the substitution reaction of the carbon heterocyclic ring of polysaccharide molecules is the inherent reason for bamboo dyeing. For instance, the bamboo treated with nitric acid presents a bright red wine color, and C=N, –NO2 functional groups are detected. Polyethylene glycol filled in the three-dimensional network avoids the water-soluble nutrients from emigrating to the surface of bamboo. The interruption of the continuous supply route allows the modified bamboo to obtain excellent antibacterial performance. Bright color and anti-microbial corrosion characteristics make the modified bamboo as a green building material has more potential applications.

Elastic hydrogel is a promising material category for designing biological muscles, repairable building materials, flexible electronic devices, and vulcanized rubber substitutes, which is required to have a long life, good self‐healing performance and extreme temperature tolerance. Herein, a super‐elastic mineral hydrogel is developed with long‐lasting moisture, based on dynamic physical crosslinking between hydrated calcium ion clusters and amide groups of polyacrylamide (PAM). The complex hydrogel exhibits a super stretchability of 13 600% at room temperature, and can maintain the super flexibility in a wide temperature range of −40–50 °C or for a long period of 28 days. Particularly, the soft material cannot be ignited under an open flame at 400–500 °C, because of coupling dual flame retardant mechanisms containing the endothermic effect of liquid water evaporation and the barrier effect of calcium mineral salt on oxygen. In conclusion, the novel complex hydrogel with excellent tensile property, stability in extreme temperature or long operating time, and flame retardancy may become a promising candidate in the fields of agriculture, food, construction, medicine, and machinery., Dynamic physical crosslinking of calcium (II) with in situ polymerized polyacrylamide provides a new mechanism for stress/energy dispersion of soft materials during stretching. As‐prepared complex hydrogel exhibits stable mechanical performance for a long‐term or under extreme temperature, and has ideal flame‐retardant ability due to the water‐locking effect of calcium (II) and barrier effect on oxygen.

Super-elastic phase change materials (SPCMs), as brand-novel smart materials, have a wide range of potential applications in stress induction, thermal energy storage and temperature control. Polyacrylamide-based HAH@PEG_12h SPCMs with an ultimate tensile ratio greater than 500% were synthesized for the first time by a popular molecular self-assembly technology. In-situ polymerized polyacrylamide (PAM) builds a reversible deformable three-dimensional network, while the filled PEG2000 PCMs form hydrogen bonds with its amino group (–NH2). 260% tensile ratio is impossible to cause obvious liquid leakage for the HAH@PEG2000 form-stable phase change material, even exceeding the melting temperature of the PEG2000 PCM. Reversible PAM–NH2⋯O–PEG hydrogen bond can also reduce the sensitivity of the polyacrylamide-based hydrophobically associated hydrogel (HAH) to air humidity fluctuations. Volumetric deformation ratio of the as-prepared PCM gel is close to zero during water vapour adsorption/desorption, which is much lower than that of the HAH without PEG2000 (20 vol%). Water molecules entering the self-prepared SPCMs are preferentially adsorbed by the PAM 3D architecture, which significantly improves the anti-interference ability of the PEG PCMs. The outstanding comprehensive performance makes the HAH@PEGs SPCMs have great potential in the future.