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Cover: 2D conjugated microporous polymers (CMPs) composed of alternate phenylene and ethynylene units are synthesized by cross‐coupling polymerization of 1,3,5‐triethynylbenzene and 1,3,5‐tribromobenzene. Spherical, tubular, and plate‐like structures are produced during the polymerization by varying the organic solvent used, and hence the organic solvent storage capacity can be altered. Further details can be found in the article by D. Tan, W. Fan, W. Xiong, H. Sun, Y. Cheng, X. Liu, C. Meng,* A. Li,* and W. Deng* .

Two-dimensional conjugated microporous polymers (CMPs) composed of alternative phenylene and ethynylene units are synthesized, by cross-coupling polymerization of 1,3,5-triethynylbenzene and 1,3,5-tribromobenzene with various solvents. Our work shows that the morphology of CMPs is greatly affected by the choice of solvents used in synthesis. Sphere, tubular, and plate-like structures are received by using the toluene, p-xylene, and mesitylene solvents, respectively. Our results demonstrate that the morphology of CMPs affects the storage capacity for organic solvents remarkably, with the plate-like CMP showing best performance. This work is expected to provide useful guidance to rationally design CMPs as absorbent materials for organic solvents.

Content uniformity of low dose blends with fine active pharmaceutical ingredients (API) is adversely impacted due to API agglomeration caused by high powder cohesion. Dry coating using high-intensity vibratory mixing is employed to reduce API cohesion and granular Bond number as well as agglomeration as predicted by contact models, hence improve blend content uniformity (CU). Micronized acetaminophen (mAPAP) (~10μm), a model API, was dry coated with nano-silica R972P (20nm), and mixed with Avicel 102. The amount of silica was varied from 0 to 2.74wt%, corresponding to theoretical surface area coverage (SAC) from 0 to 100% respectively. Bulk density, unconfined yield strength, and dispersive surface energy results indicated dry coating with 0.27 to 1.0wt% silica was adequate for API property enhancement; further corroborated by improved CU for 5wt% API blends. Excellent CU was achieved for 3, 5 and 10wt% API loaded blends, where 30min of mixing was found to be acceptable for all three. The CU with dry coated mAPAP was significantly lower and within the acceptable range as compared to control blends without silica, as well as those with silica added during blending. Sieving of mAPAP illustrated the reduction in mAPAP agglomeration, necessary for improved CU after dry coating, corroborating model based predictions. Compared to theoretical predictions, actual CU was higher unless API agglomerate size distribution obtained via sieving was taken into account. Overall, cohesion reduction by dry coating is shown as a promising approach for improving content uniformity of cohesive API blends.

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The preparation of ethyl acetoacetate is a distinctive, century-old classic organic chemistry laboratory project. Ethyl acetate and sodium metal (sodium ethoxide) are reacted by Claisen ester condensation to produce the sodium salt of ethyl acetoacetate and then obtain the refined product by acidification as well as washing, drying, and distillation under reduced pressure. This article analyzed the reasons for the low product yield and poor purity of the traditional experimental method and found that ethanol was the key to the final product. The improved experimental method used rotary evaporation and washing with saturated calcium chloride solution to remove ethanol. The new experimental method not only retains the characteristics of the original experiment and improves the product yield, but also adds the interesting phenomenon of pointing water into “ice”, which cultivates students’ learning interest and innovation and achieves a good teaching effect.