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Metal–organic framework nanoparticles (MOF NPs) have emerged as an important class of materials that display significantly enhanced performance in many applications compared to bulk MOF materials; their synthesis, however, commonly involves a tedious sequence that controls particle size and surface properties in separate steps. Now, a simple strategy to access functional MOF NPs in one pot is reported that uses a polyMOF ligand possessing a polymer block for surface functionalization and a coordination block with tunable multivalency for size control. This strategy produces uniform polyMOF‐5 NPs with sizes down to 20 nm, displaying exceptional structural and colloidal stability upon exposure to ambient conditions. A detailed time‐dependent study revealed that the polyMOF NPs were formed following an aggregation‐confined crystallization mechanism. Generality was demonstrated through the synthesis of well‐defined polyUiO‐66 NPs. [ABSTRACT FROM AUTHOR]

Using salt-doped polystyrene- b -poly(2-vinylpyridine) star shaped block copolymer as a model, we show that the architecture of (A- b -B) n type multi-arm star block copolymers enhances the ordering of the block copolymers, enabling the generation of nanostructures with microdomain periods less than 10 nm. The influence of the arm number on the order-to-disorder transition temperature and molecular weight was systematically studied using small angle X-ray scattering. The configurational constraints placed on the chains by anchoring each block copolymer to a central junction point have a significant effect on the disorder-to-order transition behavior. In addition to an increase in the Flory-Huggins parameter ( χ ), block copolymers with multi-arm star shape chain architecture have a critical segregation strength ( χN ) C that decreases with arm number, opening a simple route to generate ordered nanostructures with periods below 10 nm. [ABSTRACT FROM AUTHOR]

A polychloromethylstyrene- b- polypolycyclooctene- b -polychloromethylstyrene ABA triblock polymer was used as a backbone in a study to produce a chemically and mechanically robust anion exchange membrane (AEM). The material is easily scalable and the polypolycyclooctene segment (low T m ) makes the membrane flexible to handle. Comparison of the non-crosslinked triblock polymer functionalized with different cations namely; piperidinium, pyrrolidinium, tris(2,4,6-trimethoxyphenyl) phosphonium, and the benchmark trimethylammonium cation showed that the piperidinium functionalized membrane with an ionic exchange capacity of ca. 1.36 mmol.g − 1 had the highest OH − conductivity ca. 95 mS·cm − 1 at 80 °C, 95% RH, and the highest Cl − conductivity of ca. 31 mS·cm − 1 at 70 °C, 95% RH. The membrane with the piperidinium cation was the most chemically stable when immersed in 1 M KOH at 80 °C (with only 16% degradation after 14 days) compared to all the other cation functionalized membranes studied here. Photo-crosslinking with 1,10-decanedithiol (DT) eliminated the melting behavior of the polycyclooctene black and improved the mechanical stability of the films allowing < 20 μm large area transparent membranes to be produced. The DT cross-linking reduced the membrane swelling on all length scales as shown by small angle X-ray scattering, water uptake, and dimensional swelling data, and allowed the membrane to be fully intact even at fully hydrated states based on the tensile strength measurements. [ABSTRACT FROM AUTHOR]