The development of switchable adhesives for reversible bonding and debonding can overcome the problems associated with conventional adhesives in separating, recycling, and repairing glued surfaces. Here, a photoresponsive azobenzene-containing polymer (azopolymer) is developed for photocontrolled adhesion. The azopolymer P1 (poly­(6-(4-(p-tolyldiazenyl)­phenoxy)­hexyl acrylate)) exhibits photoinduced reversible solid-to-liquid transitions due to trans–cis photoisomerization. Trans P1 is a solid that glues two substrates with a stiffness comparable to that of conventional adhesives. UV light induces trans-to-cis isomerization, liquefies P1, weakens the adhesion, and facilitates the separation of glued substrates. Conversely, visible light induces cis-to-trans isomerization, solidifies P1, and enhances the adhesion. P1 enables photocontrolled reversible adhesion for various substrates with different wettability, chemical compositions, and surface roughness. P1 can also be implemented in both dry and wet environments. Light can control the adhesion process with high spatiotemporal resolution when using P1 as a switchable adhesive. Photoinduced reversible solid-to-liquid transitions represent a strategy for materials recycling and automated production processes that require reversible bonding and debonding.

In the cutting-edge field of cancer therapy, noninvasive photothermal therapy (PTT) has received great attention because it is considered to overcome the drawbacks of conventional surgery, radiotherapy and chemotherapy of severe body injuries and side effects on the immune system. The construction of PTT therapeutic and theranostic nanoplatforms is the key issue in achieving tumor targeting, imaging and therapy in a synergetic manner. In this review, we focus on the recent advances in constructing PTT therapeutic and theranostic nanoplatforms by integrating nanomaterials and functional polymers. The noninvasive photothermal cancer therapy mechanism and achievement strategies of PTT therapeutic and theranostic nanoplatforms are presented as well as the innovative construction strategies and perspectives for the future. Owing to their high tumor ablation efficiency, biological availability and low- or non-toxicity, PTT therapeutic and theranostic nanoplatforms are promising and emerging in medicine and clinical applications.

Design and fabrication of highly efficient electromagnetic wave absorbing materials are yet challenging tasks, mainly caused by the lack of the in‐depth understanding of structure–property relationship. Herein, significant morphology effect on electromagnetic wave absorption is uncovered by pyrolyzing two isomeric metal–organic frameworks (MOFs: MIL‐101‐Fe and MIL‐88B‐Fe). The resultant pyrolyzed nanocomposites from these two MOFs with different topology under same pyrolysis condition have almost identical chemical composition (i.e., element type, element content, and valence state) and microstructure (i.e., particle size, pore size, and volume). As far as it is known, this work represents the first study on morphology control for superior electromagnetic wave absorption in carbon‐included composite system. Notably, an excellent performance of minimum reflection loss of −59.2 dB with a thickness of 4.32 mm and effective absorption bandwidth of 6.5 GHz with a thickness of 2 mm are achieved by Fe/C‐700@101 (700 represent the pyrolysis temperature; 101 stands for MIL‐101 precursor) and Fe/Fe3C/C‐800@101, respectively. This contribution will shed the light on design of advanced electromagnetic wave absorbers in future, especially from the perspective of fine morphology control.

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SnO2 aqueous colloids as electron transport layers (ETLs) have been widely employed in planar perovskite solar cells (PSCs). However, the surface defects and energy level mismatch at the SnO2 ETL/perovskite interface are still great challenges for the power conversion efficiency (PCE) improvement. Herein, a natural and nontoxic phytic acid (PA) compound is introduced into the SnO2 aqueous colloids to prepare the ETL to depress its defects, and systematically study the influence of different PA complexation on the photovoltaic performance of PSCs. The results demonstrate that PA complexation can assemble unique coordination complexes between PA and SnO2 nanocrystals (NCs) in a new bonding of SnOP, which can passivate SnO2 inherent surface defects and tune the electronic properties of SnO2 ETLs. PA complexation can significantly disaggregate the SnO2 oligomers and reduce the cluster size distribution from 98.37 to 15.87 nm. Meanwhile, the reduction of surface trap states inhibits the potential barriers, thus the electrical conductivity is about two times as high as compared with the pristine SnO2 ETLs. Consequently, a high PCE of 21.43% in PA‐SnO2‐based PSCs is obtained, which presents an improvement of 10.9% over that of the pristine SnO2‐based PSCs.

According to the definition and physical meaning of m-CI, as a contrast, a normalized parameter m-CI can be used to analyze intramolecular cyclization of HyperMacs, which can eliminate the difference of degree of functionality (n value in A 2 +B n strategy). As shown in Figure 12, a uniform criteria value of 1 was used as a reference for completely cyclized polymers. Once normalized, the m-CI located in the range of 0.77-0.93 for the HyperMacs-C 2 , C 4 and C 8 (polytriazole), according to the change characteristics as shown in Figure 7. Besides, the m-CI of HyperMacs-PEG-polytriazole is equal to 0.86 (in the range of 0.5-1.0). And the m-CI of HyperMacs-polyester is changed from 1.01-1.07 to 0.67-0.71 (unpurified) and 1.03-1.12 to 0.69-0.75 (purification three times by solvent precipitation), respectively. Obviously, the trend of either N A /N B or m-CI is the same. In another word, m-CI closer to 1 means higher intramolecular cyclization of HyperMacs. The long chain backbones can induce more intramolecular cyclics during the A 2 +B 3 step-wise polymerization either via Cu-catalyzed azide-alkyne cycloaddition click chemistry or classic esterification reaction.

Hyperbranched polymers (HPs) have widely been used for drug delivery owing to their highly branched topology, which endows the HPs with a large amount of intramolecular cavities for drug encapsulation and terminal groups for drug conjugation. Additionally, one-pot, large-scale preparations enable the easy fabrication of HPs for biomedical applications. This review provides an overview of the synthesis of HPs and their application for drug delivery. First, we introduce a diversity of methods for the synthesis of HPs with controllable topologies. Subsequently, we discuss drug encapsulation and drug conjugation by using HPs. Finally, we highlight the use of HPs with controllable topologies for promising drug delivery.

Incorporating graphene into epoxy composites is a facile strategy to improve their mechanical performances. However, the uniform and reliable dispersion of graphene within epoxy matrix remains a large challenge owing to the intrinsic difference in chemical properties. Here, pyrene‐functionalized polyethylene glycol (Py‐PEG‐Py) was easily synthesized and utilized as a dispersant to homogenize graphene. The effect of graphene loading on mechanical performances of reinforced epoxy composites was also investigated. As 0.01 to 0.05 wt% of graphene were incorporated in epoxy resin, the resulted composites exhibited excellent improvement in flexural strength and fracture toughness compared with neat epoxy. Typically, the flexural strength increased from 63.57 ± 1.5 MPa for neat epoxy to 108.36 ± 1.9 MPa (about 70.5%) for composite, and the fracture toughness (KIC) increased from 1.25 MPa m1/2 for neat epoxy to 2.15 MPa m1/2 (around 72%) for composite modified with only 0.04 wt% of graphene and 4 wt% of Py‐PEG‐Py. Crack pinning caused by well dispersed graphene was contributed to enhancement of the fracture toughness. This work reveals a tiny amount graphene can also largely improve the mechanical properties of composites, providing a feasible approach to disperse graphene and fabricate high performance graphene composites.