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Abstract Plants produce a wide range of bioactive phytochemicals, such as antioxidants and vitamins, which play crucial roles in aging prevention, inflammation reduction, and reducing the risk of cancer. Selectively harvesting these phytochemicals, such as lycopene, from tomatoes through the adsorption method is cost‐effective and energy efficient. In this work, a templated synthesis of 3D‐printed crosslinked cyclodextrin polymers featuring nanotubular structures for highly selective lycopene harvesting is reported. Polypseudorotaxanes formed by triethoxysilane‐based telechelic polyethylene glycols and α‐cyclodextrins (α‐CDs) are designed as the template to (1) synthetically access urethane‐based nanotubular structures at the molecular level, and (2) construct 3D‐printed architectures with designed macroscale voids. The polypseudorotaxane hydrogels showed good rheological properties for direct ink writing, and the 3D‐printed hydrogels were converted to the desired α‐CD polymer network through a three‐step postprinting transformation. The obtained urethane‐crosslinked α‐CD monoliths possess nanotubular structures and 3D‐printed voids. They selectively adsorb lycopene from raw tomato juice, protecting lycopene from photo‐ or thermo‐degradations. This work highlights the hierarchically templated synthesis approach in developing functional 3D‐printing materials by connecting the bottom‐up molecular assembly and synthesis with the top‐down 3D architecture control and fabrication. 

Thermo-responsive 3D-printed hydrogels that are composed of methylated α-cyclodextrin polyrotaxanes have been synthesized through post-3D-printing methylation. With a high methylation degree of the threaded α-cyclodextrins, the fabricated monolith exhibits a two-stage thermo-induced aggregation behavior, in which a second micro-crystallization process was identified for the first time. The methylated polyrotaxane monoliths possess reversible temperature-dependent size, transparency, and elastic moduli switching in an aqueous environment. Through dual-material 3D printing, the 3D-printed monolith actuates back-and-forth at different temperatures. 

Abstract The development of integrated systems that mimic the multi‐stage stiffness change of marine animals such as the sea cucumber requires the design of molecularly tailored structures. Herein, we used an integrated biomimicry design to fabricate a sea cucumber mimic using sidechain polypseudorotaxanes with tunable nano‐to‐macroscale properties. A series of polyethylene glycol (PEG)‐based sidechain copolymers were synthesized to form sidechain polypseudorotaxanes with α‐cyclodextrins (α‐CDs). By tailoring the copolymers’ molecular weights and their PEG grafting densities, we rationally tuned the sizes of the formed polypseudorotaxanes crystalline domain and the physical crosslinking density of the hydrogels, which facilitated 3D printing and the mechanical adaptability to these hydrogels. After 3D printing and photo‐crosslinking, the obtained hydrogels exhibited large tensile strain and broad elastic‐to‐plastic variations upon α‐CD (de)threading. These discoveries enabled a successful fabrication of a sea cucumber mimic, demonstrating multi‐stage stiffness changes.