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Transitioning from the fossil fuel era to a sustainable future requires increasing adoption of high-performing renewable materials in industrial applications. Natural polymers derived from lignocellulosic materials are often considered more environmentally friendly than their petroleum-based synthetic analogs. Aeschynomene aspera, commonly known as Shola, has been found to be a large source of amorphous cellulose and a useful sorbent for the removal of oil from water. The Shola pith, the pure white inner stem, is rich in cellulose and has an exquisite three-dimensional and hierarchical porous architecture created by nature. The pith consists of about 70 wt% cellulose as the main chemical component, which is much higher than what is found in other lignocellulosic sources. In addition, the pith has about 12 wt% hemicellulose, 2–3 wt% pectin, 10 wt% lignin, 2.5 wt% wax, and 2 wt% protein as other chemical components. It was observed that water has a high contact angle (135°) on the surface of the pith, while oil droplets instantly spread on the surface, indicating excellent hydrophobic–oleophilic properties. Further studies reveal that the Shola pith exhibits a fast and high sorption capacity of 40–60 g/g for various oils and organic liquids. Silicone oil shows a sorption capacity of about 166 g/g. When applied to oil-floating-over-water, the Shola pith exhibits high selectivity for oil over water; almost all oil on the surface could be removed, leaving no trace of oil on the water surface. The Shola pith can also efficiently separate oil from an oil-in-water emulsion. This behavior is unprecedented in natural sorbents. The used material sorbs a considerable volume of the oil even after the 7th cycle. Furthermore about 95% of sorbed oil could be recovered from the material by solvent extraction. This study reveals for the first time some of the unique and interesting properties of Shola, a widely found biomass native to the eastern parts of the Indian subcontinent, and opens up possibilities of exploiting it for valuable applications. [ABSTRACT FROM AUTHOR]

The diesterification of carbonic acid with hydroxy compounds generates organic carbonates. The types of organic carbonates formed depends on the characteristics of hydroxy compounds. Dimethyl carbonate is the simplest among the various types of organic carbonates. The synthesis of organic carbonates using a phosgenation technique, oxidative carbonylation, metal carbonates, carbonation interchange reaction, reaction of urea with alcohols/phenols, and reaction of oxiranes with carbon dioxide are discussed. The application of various organic carbonates are also given.

ABSTRACT Well-defined multiarmed star random and block copolymers of ε-caprolactone with l-lactide with controlled molecular weights, low polydispersities, and precise numbers of arms were synthesized by the ring-opening polymerization of respective cyclic ester monomers. The polymers were characterized by 1H-NMR and 13C-NMR to determine their chemical composition, molecular structure, degree of randomness, and proof of block copolymer formation. Gel permeation chromatography was used to establish the degree of branching. Star-branched random copolymers exhibited lower glass-transition temperatures ( Tg's) compared to a linear random copolymer. When the star random copolymers were melt-blended with poly( l-lactic acid) (PLA), we observed that the elongation of the blend increased with the number of arms of the copolymer. Six-armed block copolymers, which exhibited higher Tg's, caused the maximum improvement in elongation. In all cases, improvements in the elongation were achieved with no loss of stiffness in the PLA blends. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 43267. [ABSTRACT FROM AUTHOR]