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The polymerization of triple-bond building blocks will generate functional polymers owing to their unsaturated backbones, which facilitate the electron delocation within the main chains. Currently, the research focus in this area is the alkyne-based polymerization, and the carbon–nitrogen triple-bond based polymerization to produce stable nitrogen-containing polymers is rarely reported. In this paper, a new polymerization of diisocyanoacetate was successfully established. The silver acetate-catalyzed polymerization of diisocyanoacetate in the acetonitrile or DMF readily produced soluble polyimidazoles with high molecular weights (M w up to 32500) in excellent yields (up to 94%) at room temperature after 2 h. Moreover, this polymerization performed in a single component fashion, which shows remarkable advantages over the traditional two- or multicomponent ones. In addition, the resultant polyimidazoles could be postfunctionalized to yield ionized polyelectrolytes and could feature the aggregation-induced emission (AIE) characteristics by incorporation of an AIE-active tetraphenylethene moiety in its polymer chains. This single component polymerization will become a powerful tool for the preparation of polyimidazoles and be potentially applicable in materials and biological fields.

As an important nitrogen source, isocyanides have been involved in numerous organic reactions. As a result, many complicated compounds have been successfully synthesized through isocyanide chemistry. However, compared with its popular research in organic reactions, the application of isocyanides in polymerization is less investigated. In this work, a new polymerization based on isocyanide monomers is established. By simply mixing diisocyanoacetates and dialdehydes in the presence of a catalytic system of CuCl/PPh3/organobase in dichloromethane at room temperature readily produces soluble and thermally stable oxazoline‐containing polymers with moderate weight‐averaged molecular weights (Mw up to 11 200) in excellent yields (up to 97%) after 6 h. Furthermore, introducing the tetraphenylethene moiety into the main chains endows the resultant polymers with aggregation‐induced emission, which can function as fluorescent probes for Fe3+ ion detection with high sensitivity and selectivity. This work not only enriches the family of isocyanide‐based polymerizations but also provides an efficient tool for the preparation of functional heterocycle‐containing polymers.

Cellulose nanofibers (CNFs) with an average diameter 8 nm were isolated from corncobs using a stepwise method that included steam-explosion pretreatment, alkaline treatment, sodium hypochlorite bleaching, high-speed blending, and ultrasonic treatment. This mechanochemical method used only two chemical reagents in low concentrations to remove non-cellulosic components. The removal of non-cellulosic components was confirmed by Fourier-transform infrared spectroscopy. X-ray diffraction revealed an increase in crystallinity during steam explosion and subsequent mechanochemical treatments. Pretreatment by steam explosion caused the partial hydrolysis of hemicellulose and loosened the structure of raw materials, which facilitated the subsequent chemical processes. The thermal stability and morphology of samples at different stages were also investigated. Steam explosion increased the thermal stability of hemicellulose and cellulose components, as it removed a fraction of hemicellulose. High-speed blending reduced the entanglement of cellulosic fibers and created uniform size. Ultrasonic treatment was used in the final step of nanoscale fibrillation. The method used in this study is environmentally friendly and has the potential to be applied at industrial scale.

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The selective separation of sulfapyridine (SPD) from sulfaquinoxaline (SQX) is investigated by applying high performance liquid chromatography (HPLC) with molecularly imprinted polymer (MIP) as the stationary phase. Herein we report the synthesis of a molecularly imprinting polymer, SPD-MIP, by free radical polymerization process. Because of this powerful method synthetic polymers with specific binding sites to template molecule are provided. In addition, the separation performances were represented by using buffer/acetonitrile (3/2, v/v) as mobile phase under 272 nm UV detection. In order to compare the chromatographic data from the stationary phase, capacity factor (k') and separation factors (α) were given. The value of 2.71 (α) revealed that the MIP was able to recognize structurally subtle differences from the template molecule. Our results are discussed with regard to the amount of template, the composition of the chromatographic mobile phase and adsorption capacity.

The Cu(I)‐catalyzed click polymerization fully meets the trend of developing powerful and economic tools for facile synthesis of functional polymers. However, the use of Cu(I) catalyst generally results in polymers with high copper residuals, which complicate the polymer purification and limit their applications. Moreover, these catalysts can only be used one time. Inspired by the report that Fe3O4‐based nanoparticles can be used as magnetically recyclable catalysts, these magnetic nanoparticles are used to produce Fe3O4/SiO2/Cu2O catalysts. These magnetic nanoparticles can efficiently catalyze the azide–alkyne click polymerization under mild reaction conditions, producing 1,4‐regioregular polytriazoles with high molecular weights in excellent yields. The copper residuals in the polymer products are much lower than those catalyzed by the conventional Cu(I) catalysts. Moreover, the Fe3O4/SiO2/Cu2O can be recycled and reused for at least 12 times. Introducing aggregation‐induced emission (AIE)‐active tetraphenylethylene unit into the polymer main‐chains endows the resultant polymer with AIE feature, too. Thus, this work not only simplifies the polymer purification procedures, but also provides a general strategy to reduce the copper residues in the polymers.

Regulation of stereochemistry is one of the most important research focuses in synthetic polymer chemistry; however, this area should be further developed. In this work, a new polymerization of diisocyanoacetates and disulfonimines with tunable stereochemistry was developed. Diisocyanoacetates and disulfonimines could easily undergo polycycloaddition in the presence of CuCl/PPh 3 , and polyimidazolines with high weight-average molecular weights (M w , up to 43 900) were produced in excellent yields (up to 99%). Moreover, the stereochemistry of the polymerization and the stereoregularity of the resultant polymers can be fine-tuned by triethylamine (TEA). In addition, TEA could also significantly promote the polymerization, from which polymers with much higher molecular weights (M w up to 155 400) could be obtained in higher yields. This work not only promotes the development of the isocyanide chemistry and enriches the family of polymerizations based on triple-bond building blocks but also provides an opportunity to study the structure−property relationship of the polyimidazolines.