The phase change sub-microcapsules (PCMCs) with the particle size of 100 nm to 1 μm have a great application potential in the field of hybrid materials for solar energy storage, while the preparation of PCMCs remains challenging without ultrasonic treatment and high-speed (>1000 rpm) homogenization. Herein, PCMCs with readily tunable phase change properties are prepared via facile, robust ab initio emulsion polymerization. The PCMCs present the quasi-monodispersed particle morphologies with the tunable particle size from 159 to 383 nm depending on the loading content of acrylic acid and the free surfactant. The latent heat density and phase change temperature of the PCMCs can be tuned from 66.6 to 115.2 J/g and from 20.8 to 65.4 °C, respectively, depending on the loading content and the type of phase change cores. The PCMCs confirm the latent heat efficiency of about 1, the high thermal reliability, and the high shape stability. The PCMCs can be functionalized by polyaniline coatings with an efficient photothermal effect. The robust, versatile approach to functionalized PCMCs can provide an alternative opportunity for the development of the next-generation smart thermal energy materials.

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There are many reports in the literatures on the use of phase change materials (PCMs) with photothermal conversion to store and harness solar energy. However, few works have reported intelligent PCMs with thermochromic capabilities that can controllably adjust their photothermal conversion efficiency to change the heating rate through temperature response. In this work, thermochromic phase change materials (TC‐PCMs) are successfully prepared by integrating the reversible thermochromic microcapsules into dynamically cross‐linked PCMs. The designed TC‐PCMs have a high photothermal conversion efficiency by using different styles of reversible thermochromic microcapsules, which can intelligently adjust the surface color of TC‐PCMs according to the substrate temperature under illumination conditions. Based on the fast temperature‐responsive thermochromic function of TC‐PCMs, the intriguing function of the reversible information storage and encryption can be realized by designing the shape and space of TC‐PCMs under the only thermal‐triggered condition. Importantly, the process of information storage and encryption can be controllable and reversible when repeatedly increasing and decreasing the external temperature. Additionally, TC‐PCMs capable of reprocessing ability based on dynamic oxime bond, are beneficial to the preparation of complex shape devices and recycling, expanding the application field of TC‐PCMs.

According to actual needs, the adhesives can achieve switchable attachment to material surfaces and subsequently reuse. [7,8] Introducing dynamic bonds into the molecular structure is an effective way to develop switchable adhesives due to their designability and reversibility. Upon exposure to an appropriate stimulus, dynamic bonds will undergo reversible breaking to realize the topological rearrangements of the network, resulting in the decrease of modulus (viscosity) along with the loss of adhesive properties. [9] While the external stimulus is removed, the dynamic bonds between the polymer segments can recombine to form the initial state, simultaneously recovering the outstanding adhesive properties. [10,11] Saito et.al incorporated dynamic boronic ester bonds into commodity triblock thermoplastic elastomers to prepare switchable/recyclable adhesive materials that exceptionally have high adhesion strength and can be debonding and re-bonding via hot pressing. [12] Furthermore, Li et al. prepared dynamic hydrogen-bonded cross-linked hydrogels with humic acid and polyvinylpyrrolidone, processing good adhesion properties and broad application as hemostatic agents. [13] Although great efforts have been made in the development of switchable adhesives, most switchable adhesives are only controlled by a single stimulus, greatly affecting their switching speed and switch efficiency. [14,15] Additionally, these adhesives are still facing the challenge of remaining good stability when exposed to repeated mechanical deformation, which greatly influences their durability, reliability, and lifetime. Thus, it is vital to develop multifunctional switchable adhesives with strong adhesion, multiple efficient switchable performance, and autonomous self-healing.It has been shown that mussels can strongly cling to a variety of material surfaces, such as rocks, ships, and other media, after withstanding the force of the constant pounding waves (Figure 1a). Recently, 3,4-dihydroxyphenylalanine extracted from mussel foot protein was proven to be the key to good adhesion ability, due to its unique ability to form multi-interac tion with various matrices. [16,17] Especially, the catechol group can form a strong complex with metal ions (Fe 3+ , Cu 2+ , Ti 3+ ) with long stability constant higher than 40 (even comparable It is a challenge to develop adhesives simultaneously capable of strong adhesion and efficient switchable ability. Herein, the authors report multifunctional switchable adhesives named Cu 2+ -curcumin-imidazole-polyurethane (CIPUs:Cu 2+ ) by introducing 1-(3-aminopropyl) imidazole and curcumin into polyurethane system crossed by Cu 2+ forming dynamic metal-ligand bonds. This CIPUs:Cu 2+ has strong adhesion (up to 2.46 MPa) on various material surfaces due to their specially designed functional groups alike the secretions from mussels. It can achieve fast switching speed (30 s) and high switch efficiency through multiple contactless remote stimulations. Importantly, density functional theory (DFT) calculation reveals tha...