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Natural fibers reinforced biopolymer composites (NFRBC) are attractive alternatives to petroleum-based plastics due to their renewability, carbon neutrality, and degradability. However, the incompatibility between the fibers and the polymer matrix has long been considered a challenging issue that prevents NFRBC from being widely used. The most common approach to overcome this problem is through surface modification of natural fibers, which always involve toxic or unsustainable reagents. Here, we focused on a cleaner and more sustainable strategy to address this issue. By using the deep eutectic solvent system, we successfully deposited a layer of lignin on the surface of the bamboo fibers to serve as a bio-coupling agent, self-supplied from the bamboo fibers rather than using exogenous lignin, petroleum-based coupling agents, or toxic reagents, which is more resource and energy efficient. The obtained bamboo fibers could simultaneously achieve interface compatibility enhancement and polylactic acid (PLA) matrix toughening. The PLA-based composites exhibited clearly better performance, including mechanical strength (the bending strength, tensile strength, impact strength, and elongation-at-break increased by 33.10%, 72.29%, 44.38%, and 40.80%, respectively), thermal stability (the T onset increased from 290.6 °C to 331.9 °C), and water resistance (the water absorption decreased from 12% to 8%). Overall, with the self-supplied bio-coupling agent applied, this work suggests a new way toward developing more sustainable, stronger, and cleaner bio-composites. • Liberating the lignin from the interior to the surface of the bamboo fibers to act as a bio-based coupling agent. • Drying the obtained fibers at 150 °C leads to a further improvement of the strength of PLA-based composites. • High thermal stability and water resistance were also achieved with the proposed strategy. • All the materials involved in this paper are non-toxic, sustainable, abundant, and ecofriendly. [ABSTRACT FROM AUTHOR]

Abstract: Chinese ink stick has a long history and a special importance in the Chinese culture. For the first time, Pyrolysis Gas Chromatography and Mass Spectrometry (Py-GC/MS) was used to identify the materials in an ancient Chinese ink stick. Four types of constituents could be detected in the archaeological ink stick of the Eastern Jin period (317–420AD): (1) borneol (Chinese name bing piàn); (2) compounds related to essential oil or tar of conifer wood: cedrene, aromadendrane, cedrane, cuparene, cedrol, retene, methyl dehydroabietate and 9-methyl retene; (3) marker compounds from animal glue; (4) polycyclic aromatic hydrocarbons (PAHs) from soot. The information obtained through this study provides conclusive evidence for use of additives of borneol and cedar oil, binding media of animal glue and pine wood soot in the ancient ink stick. [Copyright &y& Elsevier]

Heat exchanger materials with high strength and thin thickness are highly required due to the increasing demands of weight reduction and fuel economy of the automobile. In this work, 0.5 wt% Cu was added to an Al-1.5Mn-0.3Fe-0.6Si (wt.%) alloy to improve the strength. The microstructure, mechanical properties, and electrochemical properties of the tested alloys were systematically investigated. The results suggest that part of Cu is dissolved into the Al matrix, and the balance is incorporated into the Al(Mn,Fe)Si particles. Cu addition improves the strength at the expense of deteriorating the pitting corrosion resistance. On the one hand, the improved strength derives from enhanced solid solution hardening and increased nanoparticle strengthening. On the other hand, the incorporation of Cu in the Al(Mn,Fe)Si intermetallic particles increases the potential difference between the particles and the Al matrix, resulting in the deteriorated pitting corrosion resistance. Image 1 • Cu element exists in the form of Al(Mn,Fe)Si phase in Al-1.5Mn-0.3Fe-0.6Si-0.5Cu. • Cu addition produces finer grains and dense Al(Mn,Fe)Si nanoparticles. • Cu addition improves strength of Al-1.5Mn-0.3Fe-0.6Si. • Cu addition increases potential difference, so deteriorates corrosion resistance. [ABSTRACT FROM AUTHOR]

Wood is widely used in the field of building materials as a green and renewable natural porous material. With the continuous increase of global carbon dioxide emissions and increasingly serious environmental problems, improving the energy storage performance of wood is conducive to reduce carbon dioxide and regulate the temperature of the living environment. In this work, a composite phase change material is prepared by introducing stable polyethylene glycol-based energy storage polymer (PGMA) into the porous structure of delignified wood by high temperature immersion method. The wood structure has a greater influence on the crystallinity of PGMA and the modifier is widely distributed inside the lumen and also the cell wall, with crystallinity of 90% PGMA-Wood up to 8.97% and it exhibits good dimensional stability at high temperature. The thermal conductivity of 90% PGMA-Wood is increased to 0.32W/m·K, which reaches 190% higher than that of original wood for the lattice heat transfer replaces phonon heat transfer. The phase change temperature of 90% PGMA-Wood meets the comfortable indoor temperature for human with the melting enthalpy and solidification enthalpy are 25.12 J/g and 31.59 J/g, respectively. The simulated sunlight experiment shows that under the same lighting conditions, the indoor temperature of the house model made by 90% PGMA-Wood is 3 °C higher than that of the house made of original wood, which also has stronger thermal insulation performance at low temperature. All above indicates that PGMA-Wood have great potential applications in the field of solar-thermal energy conversion and storage as building insulation board and agricultural greenhouses. [Display omitted] • Green energy storage technology of wood. • Synthesis of a stable PEG-based phase change energy storage material to prevent PEG leakage. • PCES-Wood shows high phase change enthalpy and high thermal conductivity. • PCES-Wood shows good photothermal conversion efficiency and long-term thermal insulation performance. [ABSTRACT FROM AUTHOR]

• Identify connection between alkyl groups and oxidable CB surface. • Investigate the structure and chemical characteristic of alkylated CB. • Compare the dispersion ability of alkylated CB in different solutions. High dispersibility of carbon black (CB) is a great significance to its interfacial compatibility with organic or inorganic materials. We reported a type of alkyl-carbon black (aCB) nanoparticles with hydrophobic and lipophilic properties which were modified by Octadecyl isocyanate. The water contact angle of aCB was changed from 34.3°/38.9° to 102°, which exhibited excellent dispersion ability in organic solutions. Covalent modification of aCB was confirmed by the increase of particle size from 474 nm to 499 nm and the loss of organic groups at temperatures from 30 °C to 800 °C. After reaction between CB and Octadecyl isocyanate, the characteristic band of isocyanate (N C O) disappeared and formed new amide groups or carbamate, the decrease of O 1 s and C 1 s and the increase of N 1 s confirmed the alkyl chain grafted to the surface of CB. aCB showed an organic-inorganic hybrid and multi-layer substance with disordered and high crystallization capacity. [ABSTRACT FROM AUTHOR]