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Intermolecular hydrogen bonds (inter-HBs) typically act as transient cross-linkers and can enhance the intermolecular interactions. Herein, we report a counterintuitive scenario that interchain constraints of polyacrylates are alleviated by adding hindered phenols capable of forming strong inter-HB interactions with the host polymer, even if a small molecule-bridged inter-HB network apparently increases the glass transition temperature (Tg) of the hybrids. The less-constrained segmental dynamics is confirmed enthalpically by the enhanced dynamic homogeneity (i.e., an increase in nonlinearity parameter xand stretching exponential parameter β) of α-relaxation together with a remarkable increase in the physical aging rate at (Tg– 10) K. Further results clarified that xand β values are primarily governed by the strength of inter-HB interactions (Δυi), and a stronger Δυiresults in a larger xor β value. The present work provides solid experimental evidence and new molecular-level insights for the less-constrained segmental dynamics in such HB-driven hybrids in terms of the balanced flexibility between side groups and the backbone, the reduction of energy barriers hindering the cooperative motions, and the alleviation of long-chain connectivity.

Superhydrophobicity exhibited by several natural surfaces has broad application prospects due to their excellent self-cleaning and low adhesion properties. However, designing a robust superhydrophobic coating via design strategy using amorphous polymers is allimportant for industrial applications, yet rather challenging. Here, we report a scalable strategy based on the phase separation and swelling treatment to construct an ultra-durable superhydrophobic coating with hierarchical micro-/nanostructures formed by two amorphous polymers (e.g. hydrophilic and lipophilic polymers). The controlled phase separation of two amorphous polymers creates uniformly distributed microprotrusions on the coating surface and the following swelling process produces submicro-/nanobumps on the microprotrusions. Notably, when both types of polymers achieve the hierarchical micro-/nanostructures, hydrophilic polymers exhibit strong adhesion with the substrates, whereas lipophilic polymers reduce the surface energy of the system. Benefitting from the self-similar structure and the adhesive effect, the polymer-based superhydrophobic coating displays superior mechanical and chemical robustness. Furthermore, our strategy will boost the practical application of robust superhydrophobic coatings for anti-corrosion application.

Extensive investigation of the influence of the selective laser melting (SLM) process parameters on the evolution of the molten pool is of great significance to understanding microstructure control and SLM-fabricated part quality. This study focuses on the influence of the scan speed inducing the laser energy changes on the microstructural evolution, texture and phase of AlSi10Mg alloy during SLM. The microstructural evolution and characterization of the SLM-manufactured AlSi10Mg alloy were investigated by scanning electron microscope/electron backscattered diffraction (SEM/EBSD), transmission electron microscope/scanning transmission electron microscope (TEM/STEM) and X-rays diffraction (XRD). The microstructural features of the sample have shown that the primary cellular dendritic structure sizes in the coarse grain zones were about three times larger than those in fine grain zones due to the different cooling rates. Besides, the microstructure boundary contains a eutectic mixture of Al and Si while the matrix is mainly composed of α-Al. The interplanar distance between the fringes are measured as 3.84 Å and 2.86 Å corresponding to the (110) plane of Si and (110) plane of Al. On the other hand, the hardness measurement data show that the sample due to the high scan speed is larger than that of the low scan speed. Meanwhile, the (001) Al texture strength of samples in the low scan speed is stronger than those in the high scan speed. Finally, the XRD analysis reveals that no significant differences are found in the intensity of (111) α-Al, while the intensity of the (200) α-Al presents a difference because of the grain orientation and size.

Most implantable devices rely on a power supply from batteries and require replacement surgeries once the batteries run low. Mini‐generators that harvest intracorporeal energy available in the human body are promising replacements of batteries and prolong the lifetime of implantable devices, thus reducing surgery pain, risks, and cost. Although various sources of energy available in the human body are used for electricity generation using piezoelectric and triboelectric materials or intravascular turbines, concerns about material durability or thrombus risks remain, and developing novel strategies to fabricate a mini‐generator to harvest the intracorporeal energy is still challenging. Herein, a mini‐generator system is designed by exporting the systolic/diastolic blood pressure from the femoral artery of a sheep to trigger the pressure‐responsive reciprocating vertical motions of a conductor. By applying a magnetic field, an induced voltage of 0.32 V and a stable output power of 13.86 µW are obtained, which is promising to power a state‐of‐the‐art pacemaker (8–10 µW). The noncontact electricity generation strategy provides a novel avenue to sustainable power supply for implantable devices. A mini‐generator harvesting intracorporeal energy in the bloodstreamis demonstrated. By exporting the systolic/diastolic blood pressure of a sheep as a trigger, a stable output of 13.86 µW is obtained through the pressure‐responsive reciprocating vertical motions of a conductor in a magnetic field. Noncontact electricity generation out of blood vessels is a promising method to power implantable devices.

To handle the serious issue of increasing oil spill accidents, many strategies have been proposed to either clean spilt oil or separate water/oil mixture. Especially, superhydrophilic/underwater superoleophobic smart materials have recently shown advantages in overcoming problems of oil blocking and water barriers during conventional oil/water-separating process of oil-rich mixtures with superhydrophobic/superoleophilic materials. However, to the best of our knowledge, no prior reports have detailed smart materials with the wetting properties of superhydrophobic/superoleophilic that can be applied in continuous in situ separations of oil/water/oil ternary mixtures, which are common in practical oil spill cases. Herein, we describe the fabrication and efficacy of a pH-responsive smart device for continuous in situ separations of such oil/water/oil ternary mixtures without the need for ex situ treatments. In air, the superhydrophobic/superoleophilic surface of the device allowed dichloromethane to permeate through while preventing water from passing. The superhydrophilicity/underwater superoleophobicity of the device surface following alkaline treatments prevented the passage of hexane while allowing water to penetrate the device.