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Obtaining lignin-based graphite-like microcrystallites at a relatively low carbonization temperature is still very challenging. In this work, we report a new method based on condensed structures, for regulating graphite-like microcrystalline structures via the incorporation of 4,4′-diphenylmethane diisocyanate (MDI) into the main structure of lignin. The effects of MDI on the thermal properties of lignin and the graphite-like microcrystalline structure of lignin-based ultrafine carbon fibers were extensively studied and investigated. The incorporation of MDI decreased the thermal stability of lignin, increased the carbon yield and enhanced the formation of graphite-like microcrystallites, which are beneficial for reducing energy consumption during the preparation of lignin-based carbon fibers. The modified lignin-based ultrafine carbon fibers (M-LCFs) demonstrated satisfactory electrochemical performance, including high specific capacitance, low charge transfer resistance, and good cycle performance. The M-LCFs-3/2 electrode had a specific capacitance of 241.3 F g−1 at a current density of 0.5 A g−1, and a residual ratio of 90.2 % after 2000 charge and discharge cycles. This study provides a new approach to control the graphite-like microcrystalline structure and electrochemical performance while also optimizing the temperature. • Lignin-based carbon fiber with graphite structure was prepared at a low temperature. • Condensed structure facilitate the formation of graphite-like structure. • MDI decreased the thermal stability of lignin and energy consumption of carbon fiber. • MDI-modified lignin shows fascinating application in supercapacitor. [ABSTRACT FROM AUTHOR]

Crowded environments, commonly found in the food system, are utilized to enhance the properties of soybean proteins. Despite their widespread application, little information exists regarding the impact of crowded environments on the denaturation behaviors of soybean proteins. In this study, we investigated how crowding agents with varying molecular weights, functional groups, and topology affect the denaturation behavior of glycinin under crowded conditions. The results reveal that thermal stability in PEG crowded environments is mainly influenced by both preferential hydration and binding. The stabilization is primarily enthalpy-driven, with aggregation contributing additional entropic stabilization. Specifically, ethylene glycol and diethylene glycol exhibit temperature-dependent, bilateral effects on glycinin stability. At the denaturation temperature, hydrophobic interactions play a predominant role, decreasing glycinin's thermal stability. However, at a molecular weight of 200 g/mol, there is a delicate balance between destabilizing and stabilizing effects, leading to no significant change in thermal stability. With the addition of PEG 400, 1000, and 2000, besides preferential hydration, additional hard-core repulsions between glycinin molecules enhance thermal stability. Methylation modification experiments demonstrated that 2-methoxyethyl ether exerted a more pronounced denaturing effect. Additionally, the cyclization of PEG 1000 decreased its stabilizing effect. [ABSTRACT FROM AUTHOR]

Micro-to-nano transformation can make a material unique. This research uses jute microfiber to extract Holo and Alpha forms of cellulose, which are later attempted to electrospun into superfine nanofibers (NFs). Initial investigation of morphological, physicochemical, crystallographic, and thermal properties confirmed successful synthesis of Holo and Alpha-cellulose (H/A-cellulose). Afterwards, the electrospinnable concentration of H/A-cellulose was optimized and their bead-free ultrafine NFs in the range of 109–145 nm were fabricated. FTIR analysis confirmed the source composition in Holo and Alpha CNF with the partial formation of trifluoroacetyl esters. Alpha CNF exhibited better structural integrity despite the crystallinity and thermal stability deteriorated in both Holo and Alpha CNF. Both Holo and Alpha CNF exhibited adequate mechanical performance and liquid uptake properties. Alpha CNF showed better morphological stability in organic solvents and slower biodegradation than Holo CNF. Subsequent investigation revealed that both Holo and Alpha CNF didn't exhibit cytotoxic effects on COS-7 cells and above 90 % of cells were viable in contact with both CNF. Significant proliferation and attachment of COS-7 cells were noticed within 7 days of incubation with the prepared CNF. Our findings revealed that jute-extracted cellulose can be a viable and potential source for constructing cellulose-based advanced nano-biomaterials. Graphical representation of the scaffold fabrication. [Display omitted] • Extraction of Holo and Alpha-cellulose from jute fiber • Fabrication of Holo and Alpha CNF via electrospinning • Alpha CNF was more structurally stable than Holo CNF. • Holo CNF and Alpha CNF have adequate surface-wetting and liquid uptake properties. • Both Holo CNF and Alpha CNF were non-toxic against COS-7 cells and favored excellent cell proliferation and attachment. [ABSTRACT FROM AUTHOR]

Having poor interfacial compatibility between biochar microsphere (BM) and polylactic acid (PLA) should be responsible for the unbalance of composite film strength and toughness. Elucidating the effect of polydopamine (PDA) on BM and BM/PLA composite films is the ultimate goal of this study based on the mussel bionic principle. It was found that the strong adhesion of PDA on the BM surface was achieved, which improved the surface roughness and thermal stability. Also, PDA modification can facilitate crystallization, increase thermal properties, improve interfacial compatibility, and enhance the tensile properties of BM/PLA composite films. Silane-based PDA modified BM/PLA composite film exhibited the best tensile strength, tensile modulus, and elongation at break with 77.95 MPa, 1.87 GPa, and 7.30%. These noteworthy findings, achieving a simultaneous improvement in PLA strength and toughness, hold promising implications for its sustainability. [Display omitted] [ABSTRACT FROM AUTHOR]

Applications for polylactic acid (PLA) are significantly impacted by its poor mechanical properties and lack of thermal stability. The goal of this work is to bridge the gap of poor compatibility among the components and enhance their interface interlocking capability to improve the toughness and thermal stability. Ultrafine bamboo charcoal (UFBC) was treated through deep eutectic solvent (DES) method to deposit sodium lignosulfonate (LS) on its surface. LS was used with PLA as a bio-coupling agent to create an eco-friendly PLA composite film with a wide range of characteristics. Benefiting from the penetration of PLA to the internal pores in UFBC, the resultant L-UFBC/PLA film has a good mechanical interlocking structure. Ls can increase the compatibility and strengthen the interface interlocking capability through DES method, which greatly improves the mechanical properties of the system. In comparison to pure PLA one, the elongation at break was 136.24 % greater, and the crystallinity (Xc) increased from 1.09 % to 3.33 %. Furthermore, the thermal stability of the system was also improved, and the residual at 600 °C rose by 4.83 %. These characteristics offer the prepared L-UFBC/PLA film a wide range of potential applications in the packaging, medical, agricultural, and other sectors. [ABSTRACT FROM AUTHOR]

Cardanol (CD) is used as a reactive compatibilizer, and blended with polylactic acid (PLA) and polypropylene carbonate (PPC) resin (70/30(w/w)) to obtain a series of PLA/PPC/CD blends. The systematic study was conducted on the thermal properties, optical properties, rheological properties, mechanical properties, and microscopic morphology of the blend, by varying amounts of CD added to the blends. A detailed explanation and comprehensive analysis of the reaction mechanism between CD and PLA/PPC have been made. The study found that CD acts as a "bridge" between the PLA and PPC, forming the structure of a block copolymer (PLA-b-CD-b-PPC), and the copolymer can greatly improve the compatibility of PLA and PPC. When the amount of CD reaches 8 wt%, only one T g is observed in the blend, simultaneously, PLA/PPC has already transitioned from a partially compatible system to a completely compatible system. At the same time, the addition of CD does not have any negative impact on the thermal stability of the PLA/PPC blend under processing temperature conditions, and the thermal stability of the PLA/PPC/CD blends can even be improved under extreme conditions. In addition, the addition of CD allows the PLA/PPC/CD blends to maintain a high light transmittance while reducing the opacity of the blend (the light transmittance remains above 92 %, and the opacity is reduced from 37 % to about 24 %), demonstrating excellent optical properties. Moreover, the elongation at break and impact strength of the PLA/PPC/CD blend both show a trend of first increasing and then decreasing with the increase of CD amount. When the CD amount varies within the range of 6– 8 wt%, the blends undergoes a brittle-ductile transition, and its toughness is greatly improved while the rigidity can also meet practical needs. When the amount of CD in the system increases to 12 wt%, the toughness of the blend reaches its peak, and its elongation at break and impact strength reach 513.24 % and 9211.5 J/m2 respectively (increased to 2442.84 % and 270.73 % of the PLA/PPC blend). Concurrently, the fracture surface of the blend exhibits large-scale plastic flow in the direction of the applied force, with marked shear yield phenomena, showing obvious characteristics of tough fracture. [Display omitted] [ABSTRACT FROM AUTHOR]

The aim of this study was to produce new nanocomposites with antimicrobial, antioxidant and anticancer properties that can be used in biomedical research based on carboxymethyl cellulose (NaCMC) biopolymer. First, poly(2-oxo-2-(pentafluorophenoxy)ethyl-2-methylprop-2-enoate) (PPFMA) was synthesized and characterized by FTIR and NMR techniques. It was then blended with NaCMC by in situ/hydrothermal method to produce a semi-synthetic functional material. Changes in the FTIR data of the blend and the single Tg value from DSC confirmed the compatibility of the blend. To enhance the thermal and biological properties of the NaCMC-PPFMA blend, biosynthesized Ag-ZnONPs were hydrothermally incorporated into the blend at different weight ratios. The prepared materials were characterized by SEM, EDX, TEM, XRD and FTIR. The thermal stability of the materials was determined by thermogravimetric analysis (TGA), and glass transition temperatures (Tg) was determined by differential scanning calorimeter (DSC). The oxidant, antioxidant, antimicrobial, and cytotoxic properties of PPFMA, Ag-ZnONPs, PPFMA-NaCMC blend, and nanocomposites were investigated in detail. The total oxidant state (TOS) value of the NaCMC-PPFMA blend, which was 0.72 μmol equivalent H 2 O 2 /L, increased to 7.2–10.4 μmol equivalent H 2 O 2 /L with the addition of Ag-ZnONPs. Ag-ZnONPs decreased total antioxidant state (TAS) levels of the nanocomposites while increasing their oxidant activity. Therefore, an increase in the antimicrobial activity of the nanocomposites was observed. Adding Ag-ZnONPs to the NaCMC-PPFMA blend increased the thermal stability by 22 °C and the Tg value by 9 °C. Finally, the potential of Ag-ZnONPs containing nanocomposites in wound healing therapies was examined. The findings suggest that nanocomposites prepared by incorporating Ag-ZnONPs into the semi-synthetic NaCMC-PPFMA blend can be a source of bio-safe raw materials and can be used as potential wound healers. [ABSTRACT FROM AUTHOR]

Natural polysaccharides are concerned for their high biological activity and low toxicity. Two kinds of polysaccharides were extracted from Hippophae rhamnoide L. by microwave-assisted aqueous two-phase system. Under the optimal conditions predicted by RSM model (K 2 HPO 4 /ethanol (18.93 %/28.29 %), liquid to material ratio 77 mL/g, power 625 W and temperature 61 °C), the yield of total polysaccharides reached 35.91 ± 0.76 %. Moreover, the polysaccharides extraction was well fitted to the Weibull model. After purification by Sepharose-6B, the polysaccharides from top phase (PHTP, purity of 81.44 ± 1.25 %) and bottom phase (PHBP, purity of 88.85 ± 1.40 %) were obtained. GC, FT-IR, methylation and NMR analyses confirmed the backbone of PHTP was composed of a repeated unit →4)- β -D-Glc p -(1 → 2)- α -L-Rha p -(1 → 4)- β -D-Gal p -(1 → 4)- α -D-GalA p -(1 → 3)- α -L-Ara f -(1 → 3)- α -D-Man p -(1→, while the repeated unit in PHBP was →3)- α -L-Ara f -(1 → 2)- α -L-Rha p -(1 → 4)- β -D-Glc p -(1 → 3)- α -D-Man p -(1 → 4)- β -D-Gal p -(1 → 4)- α -D-GalA p -(1→. Compared with PHTP (6.46 × 106 g/mol), PHBP with relatively low molecular weight (8.2 × 105 g/mol) exhibited the smaller particle size, better water-solubility, thermal and rheological property, stronger anti-glycosylation and α -amylase inhibitory effects. Moreover, PHTP and PHBP displayed a reversible inhibition on α -amylase in a competitive manner. This study provides a high-efficient and eco-friendly method for polysaccharides extraction, and lays a foundation for sea buckthorn polysaccharides as potential therapeutic agents in preventing and ameliorating diabetes. [Display omitted] • MA-ATPE of two polysaccharides from sea buckthorn fruits was optimized by RSM model. • There were different repeated units in the backbone structures of PHTP and PHBP. • PHBP exhibited better physical and thermal stability, rheological property than PHTP. • PHTP and PHBP were novel natural agents for preventing and ameliorating diabetes. [ABSTRACT FROM AUTHOR]