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Agricultural mulch is beneficial to agricultural production, but it will cause serious environmental pollution. Poly(butylene adipate-co-terephthalate) (PBAT) mulch has the potential to replace PE mulch to reduce the microplastic pollution in farmland soil. To clarify the effects of the aging behavior of PBAT mulch on soil microbial community composition. Four types of PBAT mulch were selected to carry out a 60-day outdoor soil aging test. The microstructure, Fourier transform infrared spectroscopy (FTIR), thermal properties of PBAT mulch and the soil microbial community composition were tested after aging. The results indicated that the addition of starch could accelerate the aging of PBAT mulch, while the addition of poly(lactic acid) (PLA) could slow down the aging of PBAT mulch. After 60 days of aging, the elongation at break of starch-filled PBAT mulch was significantly reduced by more than 90%. According to the characterization of aged PBAT mulch, the degradation rate of PLA in the PBAT mulch was lower than that of PBAT. The results of high-throughput sequencing showed that PBAT mulch affected the community composition of soil fungi, which led to an increase in the abundance of Mortierella and a decrease of Hanseniaspora. According to all the results of the present study, there was no evidence that degradation products of PBAT mulch would harm the farmland soil. The research results would provide theoretical support for the popularization of PBAT mulch. [Display omitted] • Four types of PBAT mulch were to simulate soil aging. • The addition of starch accelerated the aging of PBAT mulch. • Mortierella has the potential to degrade PBAT mulch. • This study did not find evidences that PBAT mulch could harm farmland soil. [ABSTRACT FROM AUTHOR]

Blocked polyisocyanates are used in single component (1 K) water‐based and powder coatings to simplify coating synthesis and reduce waste. However, the relationship between the melting point and deblocking behavior of blocked polyisocyanates is not clear. We aim to determine the influence of the melting temperature on the deblocking of methyl ethyl ketoxime (MEKO)‐blocked aromatic polyisocyanates. A toluene‐2,4‐diisocyanate trimer grafted with different mass ratios of methoxypolyethylene glycol (MPEG) is used to achieve compounds with different melting points and is blocked with MEKO. The deblocking behaviors of the polymers are investigated using Fourier transform infrared spectroscopy, differential scanning calorimetry, scanning electron microscopy, and thermogravimetric analysis. The results show that the deblocking temperature and average activation energy of the blocked polyisocyanates decrease with increase in melting point. Further, MEKO is more likely to be lost from blocked polyisocyanates having lower melting points. Furthermore, polyacrylic resins cured with blocked polyisocyanates having low melting points exhibit better properties than those having high melting points. The results reveal that the reduction in melting point induced by grafting with MPEG can significantly reduce the deblocking temperature of blocked polyisocyanates. The improvements in these properties may help achieve the low‐temperature crosslinking of blocked polyisocyanates for coating technologies. [ABSTRACT FROM AUTHOR]

This article reports the fabrication of hybrid silica nanoparticles using surface-initiated atom transfer radical polymerization (SI-ATRP) technique. The surface of silica nanoparticles were densely grafted with 2-(dimethylamino) ethyl methacrylate (DMAEMA) and then quaternized with 1-bromohexane via two methods. FTIR, H NMR, XPS, SEM, TGA, and GPC were used to determine the chemical structure, morphology, and other properties of the products. SEM images of nanocomposites showed spherical shaped morphology with an average diameter of ∼50 nm and they were direct evidences that the hybrid silica nanoparticles had uniform core-shell morphology. Evolution of GPC traces of grafted polyDMAEMA showed that the SI-ATRP could be conducted in a well-controlled manner. [ABSTRACT FROM AUTHOR]

Abstract: Polyaniline co-doped with titanium ions and protonic acid was synthesized in aqueous H2SO4 solution containing Ti(SO4)2 (pH 2), and was characterized via Fourier-transform infrared spectra, UV–vis spectroscopy, X-ray diffraction, scanning electron microscopy, energy dispersive spectroscopy and cyclic voltammetry. Its conductivity was 2.8Scm−1 at room temperature (25°C), which is the same order of magnitude as polyaniline doped with protonic acid (5Scm−1). Compared with polyaniline doped with protonic acid, it showed a better redox reversibility and cycling stability in aqueous pH 4.0 media, even in an acetate electrolyte (pH 4.0). It could be a promising material for several applications due the increase of the operating pH window of polyaniline in an aqueous environment. [Copyright &y& Elsevier]

Polyaniline film electrode was prepared by electrochemical method, and was characterized by Fourier-transform infrared (FTIR) spectra, wide-angle X-ray diffraction (WAXD) and transmission electron microscope (TEM). The sensing property of polyaniline film electrode for chlorine ion was studied by flow injection analysis. These results show that polyaniline film electrode possesses high the sensitivity and fast response time for chlorine ion, and the relationship between logarithm of maximum response current and the chlorine ion concentration is linear: lg Imax=0.8760 lg C+45.32, in the range of 10−5 to 10−2 mol/l concentrations. Lifetime of polyaniline film electrode is about 35,000 measurement numbers. [Copyright &y& Elsevier]

• Density and the excess volumes for the binary system of DEG + 1,2-PDA. • Viscosity and viscosity deviation for the binary system of DEG + 1,2-PDA. • Surface tension and surface tension deviation for the binary system of DEG + 1,2-PDA. • Intermolecular interaction of DEG + 1,2-PDA was discussed as HOCH 2 CH 2 OCH 2 CH 2 OH...NH 2 CH 2 CHNH 2 CH 3. Under atmospheric pressure of the laboratory (88.94 KPa), the density (ρ), viscosity (η) and surface tension (γ) for binary mixture system of the diethylene glycol (DEG) (1) + 1,2-propanediamine (1,2-PDA) (2) were measured in different concentration ranges at T = 293.15 K ∼ 318.15 K. According to the basic data of ρ , η and γ , excess molar volumes values (V m E), viscosity deviation (Δη), surface tension deviation (Δγ), partial molar volume ( V 1 ¯ and V 2 ¯), apparent molar volume (V φ,1 and V φ,2) and thermal expansion coeficiente (α ρ) were calculated and fitted by Redlich-Kister (R-K) equation, the least square method and other formulas. At the same time, the interaction between DEG (1) + 1,2-PDA (2) was also discussed by Gaussian 09, Fourier Transform infrared spectroscopy (FTIR), UV–visible spectroscopy (UV–vis), and Fluorescence spectroscopy (FLS) etc. The results were displayed that a hydrogen bond was formed between the nitrogen atom (N) on the amino group (–NH 2) of 1,2-PDA and the hydrogen atom (H) on the hydroxyl group (–OH) of DEG, which took the form of HOCH 2 CH 2 OCH 2 CH 2 OH⋯NH 2 CH 2 CHNH 2 CH 3. [ABSTRACT FROM AUTHOR]

Abstract: A novel chemically sulfated polysaccharide SRBPS2a with potent anti-tumor activity was derived from defatted rice bran by chlorosulfonic acid–pyridine (CSA–Pyr) method. The average molecular weight of SRBPS2a was 3.5×105 Da and the degree of sulfation (DS) was 1.29. The Fourier-transform infrared spectra (FT-IR) and 13C NMR spectroscopy analysis revealed that SRBPS2a was mainly consist of β-(1→3)-d-galactopyranosyl residues, the sulfate substitution site was on C-2 and C-4 while the side chains were cut off during the sulfated reaction. Furthermore, SRBPS2a exhibited evident growth inhibition on mouse mammary tumor EMT-6 cells both in vitro and in vivo. [Copyright &y& Elsevier]