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Thiol-acrylate photoresin containing dynamic disulfide bonds undergoes wavelength-selective photopolymerization under greenvs.UV light to produce a degradable step-growth networkvs.permanent chain-growth network. 

Abstract The creatures in nature exhibit dynamic responses to environmental stimuli through their hierarchical architectures. Benefiting from gradient porous structures,Delosperma nakurenseopens its protective valves of the seed capsules when hydrated with liquid water, increasing the likelihood that seeds are dispersed under conditions favorable to germination. Here, a versatile 4D printing technology, namely liquid crystal templating‐assisted vat photopolymerization (LCT‐VPP), which can fabricate bioinspired porous structures with hygro‐responsive capabilities by utilizing photopolymerization induced phase separation (PIPS) and liquid crystals (LCs) electro‐alignment is reported. PIPS within the LCs/nanofiller composites leads to the formation of submicrometer gradient porous structures after extracting nonreactive LCs. The electric field enables the programmable alignment of LCs, which in turn elongates the porous structures and aligns nanofillers. In addition, the programmable arranged nanofillers by the templated LCs enhance the degree of deformation and thus the resulting composites exhibit high shape control accuracy, fast dynamic response, and high reliability. This study opens a perspective for designing bioinspired smart materials with the special spatial distribution of porous structures. The results reported here can give rise to various potential applications in soft robots, smart anticounterfeiting devices, flexible sensors, and ultrafiltration membrane. 

Abstract The emerging Internet of Things (IoTs) invokes increasing security demands that require robust encryption or anti‐counterfeiting technologies. Albeit being acknowledged as efficacious solutions in processing elaborate graphical information via multiple degrees of freedom, optical data encryption and anti‐counterfeiting techniques are typically inept in delivering satisfactory performance without compromising the desired ease‐of‐processibility or compatibility, thus leading to the exploration of novel materials and devices that are competent. Here, a robust optical data encryption technique is demonstrated utilizing polymer‐stabilized‐liquid‐crystals (PSLCs) combined with projection photoalignment and photopatterning methods. The PSLCs possess implicit optical patterns encoded via photoalignment, as well as explicit geometries produced via photopatterning. Furthermore, the PSLCs demonstrate improved robustness against harsh chemical environments and thermal stability and can be directly deployed onto various rigid and flexible substrates. Based on this, it is demonstrated that a single PSLC is apt to carry intricate information or serve as an exclusive watermark with both implicit features and explicit geometries. Moreover, a novel, generalized design strategy is developed, for the first time, to encode intricate and exclusive information with enhanced security by spatially programming the photoalignment patterns of a pair of cascade PSLCs, which further illustrates the promising capabilities of PSLCs in optical data encryption and anti‐counterfeiting.