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In this study, we have for the first time demonstrated that palladium chloride (PdCl2) is an efficient catalyst for ring‐opening polymerization of cyclohexene oxide in a solvent‐free condition. The polymerization product was in atactic structure, and reaction conditions, such as reaction temperature, time, and catalyst amount, showed effects on polymerization conversion yield, turnover number, and number‐average molecular weight of the resulting poly(cyclohexene oxide). PdCl2 catalysis follows a cationic ring‐opening mechanism. The polymerization result is highly determined by the chemical structure of the monomers.

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The cycloaddition of CO2 with epoxide has been a promising way to fix CO2. Developing efficient, low-cost catalysts for this reaction is highly desired. In this paper, we report a novel cocatalyst system that consists of acrylamide and KI for the synthesis of propylene carbonate using CO2 and propylene oxide as starting materials. Different amides (i.e., acrylamide, benzamide, nicotinamide, acetamide, N-isopropylacrylamide, N-tert-butylacrylamide, and N,N-dimethylacrylamide) were combined with different potassium halides to investigate their catalysis capability. KI/acrylamide showed the highest efficiency, and a synergetic effect occurred between acrylamide and KI. At the KI: acrylamide ratio of 1:1 (mol/mol) and concentration of 2.5 mol% for both of them (based on PO), the reaction reached a yield of 95.3%. The catalytic system applies to the cycloaddition reaction using different epoxides. The reaction mechanism was proposed.

Cellulose-based fabrics are ubiquitous in our daily lives. They are the preferred choice for bedding materials, active sportswear, and next-to-skin apparels. However, the hydrophilic and polysaccharide characteristics of cellulose materials make them vulnerable to bacterial attack and pathogen infection. The design of antibacterial cellulose fabrics has been a long-term and on-going effort. Fabrication strategies based on the construction of surface micro-/nanostructure, chemical modification, and the application of antibacterial agents have been extensively investigated by many research groups worldwide. This review systematically discusses recent research on super-hydrophobic and antibacterial cellulose fabrics, focusing on morphology construction and surface modification. First, natural surfaces showing liquid-repellent and antibacterial properties are introduced and the mechanisms behind are explained. Then, the strategies for fabricating super-hydrophobic cellulose fabrics are summarized, and the contribution of the liquid-repellent function to reducing the adhesion of live bacteria and removing dead bacteria is elucidated. Representative studies on cellulose fabrics functionalized with super-hydrophobic and antibacterial properties are discussed in detail, and their potential applications are also introduced. Finally, the challenges in achieving super-hydrophobic antibacterial cellulose fabrics are discussed, and the future research direction in this area is proposed. Graphical Abstract The figure summarizes the natural surfaces and the main fabrication strategies of superhydrophobic antibacterial cellulose fabrics and their potential applications. Supplementary Information The online version contains supplementary material available at 10.1007/s42765-023-00297-1.

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Surfaces possessing desirable underliquid special wettability, particularly underliquid dual superlyophobicity, have a high potential for extensive applications. However, there is still a lack of controllable preparation strategies to regulate the underliquid wettability via balancing the underliquid lyophilicity−lyophobicity. Herein, we develop a nanocomposite coating system comprising silica nanoparticles (NPs), glycerol propoxylate triglycidyl ether (GPTE), and fluorinated alkyl silane (FAS) to obtain controllable underliquid special wettability surfaces. FAS is the vital factor in guiding the preparation of the surface coating with expected underliquid superwettability. Increasing the FAS content results in a tendency toward underwater superoleophobicity/ underoil hydrophilicity to underwater oleophilicity/underoil superhydrophobicity. Significantly, the underliquid dual superlyophobic surface can be achieved when an appropriate FAS content is located. After the coating treatment, the fabric exhibits superamphiphilicity in air and superlyophobicity in liquid (i.e., exhibiting both underwater superoleophobicity and underoil superhydrophobicity). The coating also exhibits an adaptable antioil fouling ability and high durability against harsh environments. Furthermore, oil/water separation based on the underliquid dual superlyophobicity of coated fabrics is successfully demonstrated. Our work proposes a new fabrication principle for the design of underliquid special wettability surfaces and offers broad applications, such as switchable oil/water separation, antibiofouling, liquid manipulation, and smart textiles.