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Along the development of ionic porous organic polymers, simple and efficient synthetic methods are actively pursued. Herein, the Debus–Radziszewski reaction is applied to synthesize ionic conjugated microporous polymers (iCMPs) in one step. A series of imidazolium‐linked iCMP‐X (X = 1, 2, 3) are developed for CO2 sorption and in situ conversion with epoxide into cyclic carbonates. The as‐synthesized iCMPs are characterized in detail by scanning electron microscope, solid‐state nuclear magnetic resonance, X‐ray photoelectron spectroscopy, X‐ray diffraction analysis, N2/CO2 sorption, and more. Among all synthesized iCMPs, iCMP‐1 possesses the highest specific surface area and in turn the strongest CO2 sorption capacity. Moreover, through a simple anion ion exchange reaction with halide, iCMP‐1 is transformed to iCMP‐1@Cl that embodies significant catalytic capability for converting CO2 into cyclic carbonates. [ABSTRACT FROM AUTHOR]

A main-chain polyimidazolium poly(ionic liquid) was obtained via one-step Debus-Radziszewski (DB) reaction, which was followed by anion exchange to afford the hydrophobic analogue. After confirmation of their chemical structures by nuclear magnetic resonance (NMR) spectroscopy and attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy, their thermal behavior and solubility were fully characterized. Via interpolyelectrolyte complexation with poly(acrylic acid), a new main-chain poly(ionic liquid)-based porous membrane was constructed. Upon tuning molecular weight of poly(acrylic acid), the average pore size of membranes was found to vary from 100 to 500 nm. Eventually, this porous membrane was proven to be reprocessable through treatment with a high ionic salt solution, which offers a simple but efficient method to reuse porous polymer membranes. [ABSTRACT FROM AUTHOR]

Scrutinyite SnO2 was synthesized by annealing SnO nanoparticles fabricated from micron-size SnO via ball milling. The isotropic as well as anisotropic chemical shifts of 119Sn obtained by solid-state nuclear magnetic resonance method, were verified computationally using a pseudopotential method in density-functional theory. The results fit with 6-fold coordinated Sn. A linear relationship holds empirically between isotropic shift and coordination number divided by Sn-O average bond length in all polymorphs of tin oxides. When the annealing proceeded in an oxygen-free atmosphere, metallic tin, the rutile phase of SnO2 and oxygen vacancies associated with permanent electric dipoles were also detected by thermal analysis and dielectric spectroscopy. [ABSTRACT FROM AUTHOR]

Nanocrystalline tin oxide was fabricated, with molar ratio O/Sn determined as 1.40, 1.55, 1.79, 1.92 and 1.96 from X-ray photoelectron spectroscopy. They displayed weak ferromagnetism, the sample with O/Sn = 1.55 showing the maximum saturation magnetization reaching almost 8 × 10 − 3 emu / g at room temperature. 119 Sn nuclear magnetic resonance allowed the deduction, based on four resolved resonance peaks, that their Sn ions had four possible coordination numbers, namely 3, 4, 5 and 6. The relative fraction of 4-coordinated cations was the one found to bear positive linear correlation with saturation magnetization of the sample. It is surmised that magnetism in tin oxide results mainly from 4-coordination Sn ions, of valance about +3, as estimated from the binding energies of their 3d photoelectron emission levels. [ABSTRACT FROM AUTHOR]

A polysaccharide component (SQAP-2) was isolated from quinoa by alkaline extraction and purified with DEAE-Sepharose Fast Flow and Sephacryl S-300 column chromatography. The chemical structure of the polysaccharide was characterized, and the impact on antioxidant activity was evaluated. Polysaccharide SQAP-2 (2.02 × 103 Da) is a type of glucose whose glycosidic bond Glc-(1→, →4)-Glcp-(1→, →4, 6)-Glcp-(1→ linkages were identified through gas chromatography-mass spectrometry. Nuclear magnetic resonance confirmed the monosaccharide composition and glycosidic linkage content, and a suggestion of the structural formula was provided. Their radical scavenging capacity was evaluated, and scavenging activity against DPPH, ABTS, hydroxyl, superoxide radicals, and ferric reducing ability exhibited excellent radical scavenging activities of approximately 21.71 ± 1.25%, 49.46 ± 1.59%, 70.10 ± 3.39%, 70.49 ± 2.09%, 51.25 ± 1.16%, respectively, at 3 mg/mL. The isolated quinoa polysaccharides could represent an antioxidant agent once the structural features and antioxidant activities are definitively characterized. Image 1 • A new alkali-extracted polysaccharide SQAP-2 was isolated from quinoa. • The chemical structure of SQAP-2 was characterized by FI-IR, GC-MS, 1D and 2D NMR. • SQAP-2 exhibited strong antioxidant activity. [ABSTRACT FROM AUTHOR]