This work offers a successful loop-closing strategy for increasing the sustainability and lowering the manufacturing cost of epoxy materials.

Ozonolysis is potentially an effective method for pretreating lignocellulosic biomass to improve the production of fermentable sugars via enzymatic hydrolysis. Further understanding of the ozonolysis process and identifying specific lignin structural changes are crucial for improving the pretreatment process. Investigation into pretreatment of wheat straw using ozonolysisis is reported in this paper, with special emphasis on selective modification/degradation of lignin subunits. The ozonolysis was performed for 2 h with less than 60 mesh particles in order to achieve maximum lignin oxidation. The results showed that the lignin structure was significantly modified under these conditions, leading to higher sugar recovery of more than 50% which increased from 13.11% to 63.17% corresponding to the control and ozone treated samples, respectively. Moisture content was found to be an important parameter for improving sugar recovery. Ninety percent (w/w) moisture produced the highest sugar recovery. The concentration of acid soluble lignin in the ozone treated sample increased from 4% to 11% after 2 h treatment. NMR analysis revealed that the S2/6 and G2 lignin units in the wheat straw were most prone to oxidation by ozone as the concentration of aromatic units decreased while the carboxylic acids became more abundant. The experimental data suggest the degradation of β-O-4 moieties and aromatic ring opening in lignin subunits. The pyrolysis-gas chromatography/mass spectrometry results revealed that the rate of lignin unit degradation was in the following order: syringyl > guaiacyl > p-hydroxyphenyl. Long ozone exposure resulted in few condensed lignin structure formation. In addition, the formation of condensed units during this process increased the activation energy from ASTM-E, 259.74 kJ/mol; Friedman-E, 270.08 kJ/mol to ASTM-E, 509.29 kJ/mol; Friedman-E, 462.17 kJ/mol. The results provide new information in overcoming lignin barrier for lignocellulose utilization.

Tables of X-ray data, fractional atomic coordinates, anisotropic thermal parameters, and bond distances and angles for complexes 2 and 3, a table of bond distances for 1, and a figure showing the structure of complex 1 (18 pages); listings of observed and calculated structure factor amplitudes for complexes 2 and 3 (19 pages). Ordering information is given on any current masthead page.

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HDEHP (di-2-ethylhexylphosphoric acid) is one of the extractant molecules most intensively used in liquid-liquid extraction systems. Of particular interest in this investigation is its application in the TALSPEAK process, which is among the methods currently considered to be ready for technological deployment for the separation of trivalent actinides (Am(III) and Cm(III)) from lanthanide (Ln(III)) cations. However, several fundamental features of the chemistry of this separation system are not well understood. It has become clear that the lactic acid (LacH), which is employed as a buffer in the aqueous phase, plays a very complex role in the biphasic chemistry of the system. In this study, Nuclear Magnetic Resonance ((31)P NMR) was used to investigate the rate of HDEHP (AH) exchange occurring in the binary complexes Ln(AHA)(3) (Ln = La and Sm), which are usually considered to be the predominant species present in a non-polar organic phase (1,3-diisopropylbenzene). The rate data indicate considerably faster ligand exchange kinetics for La(AHA)(3) than is seen for Sm(AHA)(3), with a corresponding shift from a dissociative interchange to an associative process. With the introduction of lactic acid (LacH) and higher concentrations of lanthanides into the system, ternary complexes (Ln(3+)-HDEHP-lactate) become dominant, as demonstrated using (31)P NMR and Electrospray Ionization Mass Spectrometry (ESI-MS). Lactate partitioning experiments indicate that the amount of lactate extracted is correlated with the concentration of Ln(3+). The terminal ternary complex species appears to have the general stoichiometry 1 : 2 : 1 (Ln(3+) : HDEHP : lactate). The detection of bimetallic ternary complexes (by ESI-MS) with La(3+) and the observation of multiple phosphorus environments (by NMR) suggest the presence of polymetallic complexes with the general formula (LaA(2)Lac)(n). A model is proposed in which DEHP(-) molecules bridge two metal ions.

A novel one-step approach for the pH-triggered electrochemically interacted exfoliation of graphene sheets in graphite oxide and simultaneous reduction and functionalization with the aid of the ionic liquid is reported. The developed method shows significant advantages over the conventional functionalized/chemically reduced graphene. Particularly, for the first time, no additional stabilizer or modifier is needed to stabilize the resulting processible graphene dispersion. The prepared graphene oxide and its functionalized graphene are characterized by SEM, TEM, FTIR, UV-vis, XRD, Raman, XPS, and NMR. The results indicate that, with the aid of the IL during the reaction, the resulting functionalized graphene shows improved organophilicity, good wettability and improved interfacial interactions as well as significant resistance to thermal degradation. The methodology paves a new way for use of the IL as a processing aid and reaction medium to promote chemical functionalization of graphene through the electrochemically interacted exfoliation of graphene sheets and can be expected to provide a new approach with great promise for its organophilic wettability and enhanced interfacial adhesion as well as improved thermal stability. Furthermore, the controlled modifications of graphene nanoreinforcements can also be expected to alter the nature of the interactions between components.

In this work, biobased hydrogels with temperature and pH responsive properties were prepared by copolymerizing N-isopropyl­acrylamide (NIPAM), itaconic acid (IA), and methacrylated lignosulfonate (MLS), where the multifunctional MLS served as a novel macro-cross-linker. The network structures of the lignosulfonate-NIPAM-IA hydrogels (LNIH) were characterized and confirmed by elemental analysis, Fourier transform infrared, and 13C nuclear magnetic resonance. The equilibrium swelling capacity of the LNIH hydrogel decreased from 31.6 to 19.1 g/g with MLS content increasing from 3.7 to 14.3%, suggesting a strong dependence of water absorption of the gel on MLS content. LNIH hydrogels showed temperature-sensitive behaviors with volume phase transition temperature (VPTT) around the body temperature, which was also influenced by MLS content. Moreover, all LNIH hydrogels exhibited pH sensitivity in the range of pH 3.0 to 9.1. Rheological study indicated that mechanical strength of the gel also increased with MLS content. The results from this study suggest that lignosulfonate derivative MLS is a potential feedstock serving both water-absorbing moiety and cross-linker for preparation of biobased smart hydrogels.

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