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Reported here is a multi-response anisotropic poly(N-isopropylacrylamide) hydrogel developed by using a rotating magnetic field to align magnetic double stacks (MDSs) that are fixed by polymerization. The magneto-orientation of MDSs originates from the unique structure with γ-Fe

Nature fascinates with living organisms showing mechanically adaptive behavior. In contrast to gels or elastomers, it is profoundly challenging to switch mechanical properties in stiff bioinspired nanocomposites as they contain high fractions of immobile reinforcements. Here, we introduce facile electrical switching to the field of bioinspired nanocomposites, and show how the mechanical properties adapt to low direct current (DC). This is realized for renewable cellulose nanofibrils/polymer nanopapers with tailor-made interactions by deposition of thin single-walled carbon nanotube electrode layers for Joule heating. Application of DC at specific voltages translates into significant electrothermal softening via dynamization and breakage of the thermo-reversible supramolecular bonds. The altered mechanical properties are reversibly switchable in power on/power off cycles. Furthermore, we showcase electricity-adaptive patterns and reconfiguration of deformation patterns using electrode patterning techniques. The simple and generic approach opens avenues for bioinspired nanocomposites for facile application in adaptive damping and structural materials, and soft robotics., Switching mechanical properties in stiff bioinspired nanocomposites is challenging as they contain high fractions of hard reinforcements. Here, the authors demonstrate reversible electrical switching in highly-reinforced cellulose nanopapers using an applied low direct current.

A generic, facile, and waterborne strategy is introduced to fabricate flexible, low-cost nanocomposite films with room-temperature phosphorescence (RTP) by incorporating waterborne RTP polymers into self-assembled bioinspired polymer/nanoclay nanocomposites. The excellent oxygen barrier of the lamellar nanoclay structure suppresses the quenching effect from ambient oxygen (kq ) and broadens the choice of polymer matrices towards lower glass transition temperature (Tg ), while providing better mechanical properties and processability. Moreover, the oxygen permeation and diffusion inside the films can be fine-tuned by varying the polymer/nanoclay ratio, enabling programmable retention times of the RTP signals, which is exploited for transient information storage and anti-counterfeiting materials. Additionally, anti-interception materials are showcased by tracing the interception-induced oxygen history that interferes with the preset self-erasing time. Merging bioinspired nanocomposite design with RTP materials contributes to overcoming the inherent limitations of molecular design of organic RTP compounds, and allows programmable temporal features to be added into RTP materials by controlled mesostructures. This will assist in paving the way for practical applications of RTP materials as novel anti-counterfeiting materials.

The transition toward future sustainable societies largely depends on disruptive innovations in biobased materials to substitute nonsustainable advanced functional materials. In the field of optics, advanced devices (e.g., lasers or metamaterial devices) are typically manufactured using top���down engineering and synthetic materials. This work breaks with such concepts and switchable lasers self���assembled from plant���based cellulose nanocrystals and fluorescent polymers at room temperature and from water are shown. Controlled structure formation allows laser���grade cholesteric photonic bandgap materials, in which the photonic bandgap is matched to the fluorescence emission to function as an efficient resonator for low threshold multimode lasing. The lasers can be switched on and off using humidity, and can be printed into pixelated arrays. Additionally, the materials exhibit stiffness above typical thermoplastic polymers and biodegradability in soil. The concept showcases that highly advanced functions can be encoded into biobased materials, and opens the design space for future sustainable optical devices of unprecedented function. The study demonstrates sustainable, switchable, and biodegradable laser devices self���assembled from cellulose nanocrystals (CNCs) as the resonator and dye���doped water���soluble polymers as the gain medium., publishedVersion

The miniaturization, integration, and lightweight of modern electronics have posed serious challenges to the development of high-performance and multifunctional thermal management materials. Here, we reported SiO2-coated nanofibrillated cellulose (NFC)/boron nitride nanosheets (BNNS) hybrid films with excellent thermal conductivity (TC) and hydrophobicity. These films were easily constructed via vacuum-assisted filtration and subsequent hydrophobic coating. The hybrid films exhibit a well-defined aligned structure with in-plane oriented BNNS. This finding was proven via wide-angle and small-angle X-ray scattering techniques, allowing for a high TC of up to 10.88 W m−1 K−1 at a low BNNS content of 7 wt%. Moreover, the hydrophobic hybrid films achieve high tensile strength (166.47 MPa) and electrical insulating property (volume resistivity = 1.2 × 1012 Ω cm). Inspired by the lotus effect, the water contact angle of such hydrophobic hybrid films reaches 143°, showing great potential in real applications for preventing the adverse effects of water and moisture.

Transmittance and haze are key properties of light diffusion materials. Hybrid light diffusion agents (LDAs) and melt-blending process are introduced to study optical performance and mechanical properties of polycarbonate (PC) light diffusion materials. Optical properties of PC composites prepared by two-step melt-blending process has better repeatability compared to one-step method due to the better dispersion state of hybrid fillers in PC matrix. The hybrid fillers silicate microspheres (SMS)/nano titania particles (nTiO2) are more suitable for PC matrix compared to cross-linked poly(methyl methacrylate) microspheres (PMMA)/nTiO2, for the reason that the PC/SMS/nTiO2 composites exhibit favorable optical performance and almost no deterioration of mechanical properties. The good balance between high transmittance and substantial haze can be achieved when the SMS/nTiO2 content is 1.2 wt% (the transmittance and haze are 60.97% and 88.73%, respectively). POLYM. ENG. SCI., 57:374–380, 2017. © 2016 Society of Plastics Engineers

Development of rational vectors for efficient drug and gene delivery is crucial for cancer treatment. In this study, epidermal growth factor receptor (EGFR)-binding peptide amphiphile (PA) were used as the primary bilayer skeleton material to construct ultra-stable self-assembling peptide nanovesicle (SPV). The resulted EGFR-targeted SPV (ESPV) could efficiently encapsulate therapeutic cargos (drugs or small interfering RNAs [siRNAs]) or labelled fluorescent cargo (quantum dots [QDs]) and exhibited excellent affinity for EGFR-positive cancer cells. Moreover, ESPV could deliver more drug or plasmid DNA to tumour sites and promote gene expression (a three-fold ratio of ESPVs vs cationic liposomes). Notably, the individual delivery or co-delivery of doxorubicin (DOX) and the acetylcholinesterase (AChE) gene via the ESPVs resulted in excellent drug/gene delivery both in vitro and in vivo and exerted a significant growth-suppressing effect on a liver cancer xenograft. This nanoscale, targeted cargo-packaging technology may provide a new strategy for the design of highly targeted cancer therapy vectors.