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In this research endeavor, we report the successful synthesis of an aminosulfonic-based ceramic additive, HLDSA, was prepared by replacing part of phenol with HLDLP, a depolymerization product of hydrolysis lignin, through Co@C metal catalysts in the synergistic alkali-catalyzed depolymerization of hydrolysis lignin to achieve high-value lignin utilization. The preparation and application conditions of the depolymerized hydrolysis lignin HLDLP and its modified product HLDSA were studied, together with a brief analysis of their mechanism of action. During application of ceramic additive, the HLDSA showed a rather excellent dispersing and flexural strength performance, with a minimum slurry outflow time of 20.81 s and a maximum flexural strength of 2.79 MPa, which was a significant improvement over that of the blank sample (59.29 s and 1.77 MPa). Meanwhile, HLDSA was contrasted with other 8 ceramic additives that are widely available on the market. The application performance of HLDSA was also better than that other ceramic additives on the market, indicating that HLDSA has a promising application. • Depolymerized hydrolysis lignin (HLDLP) was produced from hydrolysis lignin (HL) for phenolic compound. • In the depolymerization products of HL, the selectivity of phenol and 2-methoxyphenol reached 33.69% and 23.50%, respectively. • HLDSA is a kind of lignin aminosulfonic-based ceramic additive with excellent properties prepared from HLDLP instead of partial phenol. • The grinding aid, dispersion and stability of HLDSA is superior to most ceramic additives on the market. [ABSTRACT FROM AUTHOR]

Natural rubber is the only biosynthesized rubber and the most prominent of all the elastomers. Insertion of nanofillers into natural rubber matrix has received much research interest because of the enhanced mechanical, thermal, electrical, antibacterial, etc. properties of the final natural rubber nanocomposite. Molybdenum disulfide (MoS 2), an important member in transition metal dichalcogenides (TMD) is having excellent optical, thermal, mechanical, electronic and antibacterial properties. The inherent properties of this novel filler was exploited through the preparation of natural rubber-MoS 2 nanocomposites via latex dipping method in which tannic acid (TA), naturally occurring macromolecule was used as an exfoliating agent for MoS 2. MoS 2 :TA dispersions were prepared in 1:2, 1:4 and 1:6 ratios by mechanical stirring followed by sonication method for analyzing the optimum amount of exfoliating agent for the preparation of NR-MoS 2 nanocomposite. MoS 2 :TA in 1:4 ratio was found to be the optimum loading for the NR nanocomposite preparation with improved mechanical, thermal and antibacterial properties. The enhanced properties of the NR composites could be attributed to the synergistic effect of both MoS 2 and TA. The current study shows the role of TA in tuning the properties of NR/MoS 2 nanocomposites that enable their potential utilization in various biomedical applications. [ABSTRACT FROM AUTHOR]

This study reports a simple fabrication of green sugarcane (Saccharum officinarum) bagasse nanocomposite-based films with improved water barrier properties. In this work, cellulose nanofibers derived from sugarcane bagasse (SB-CNF) were employed as reinforcing agents. The reinforcing effects of varying SB-CNF concentrations, ranging from 10 to 40 wt%, on the characteristics and functionalities of nanocomposite films were measured. Our results demonstrated that the film incorporating 30 % SB-CNF into the SB matrix exhibited optimal characteristics and was chosen for further evaluation of its water barrier properties. To enhance the water barrier properties of the resulting films, different concentrations of lysozyme (0, 3.5, 7, 10.5, and 14 wt%) were incorporated into the film matrix. With the addition of 3.5 % LZ, the film exhibited enhanced water barrier properties, yielding a water contact angle of 97.60 ± 0.79°, a water solubility of 18.64 ± 0.79 %, and a water vapour permeability of 0.65 ± 0.04 g mm/m2 d kPa. The film also showcased its ability to retain water over the course of 120 minutes, with a swelling ratio of 430 %. An increase in mechanical strength (67.28 ± 0.58 MPa) and transparency (88.70 ± 0.39 %) of the film was also noted. The observed findings were attributed to the good dispersion and excellent intermolecular interactions between the lysozyme and the SB/30 %SB-CNF. These results offer a promising prospect for utilization in food packaging applications, with an emphasis on food preservation. [Display omitted] • High-speed agitation blender and ultrasonication were employed to produce SB-CNF. • 30 % of sugarcane bagasse cellulose nanofiber exhibited excellent reinforcing effects. • Incorporation of 3.5 % lysozyme showed improved water barrier properties. • SB/SB-CNF/LZ films showed great potential for use in food packaging applications. [ABSTRACT FROM AUTHOR]

In this study, a novel strategy for modifying nanocellulose (NC) by borax cross-linking was developed, and the obtained borax modified nanocellulose (BNC) was incorporated into cationized high amylose maize starch (CS) films to evaluate the applicability. Cellulose molecules were successfully cross-linked by boron ester bonds, and the original crystal type and basic chemical structure were not changed. Compared with NC, the relative crystallinity of BNC was slightly increased, and the thermal stability was obviously enhanced. Addition of NC and BNC to CS films significantly improved their tensile strength and water resistance. The dispersion of nanocellulose in CS films was effectively improved by borax cross-linking modification. CS/BNC films showed higher mechanical and water resistance properties compared with CS/NC films. Compared with pure CS film, tensile strength of the composite film with 6 wt% BNC increased about 4.0 times, and its water-vapor permeability decreased about 37%. The novel strategy for preparing BNC by using boron ester bonds will provide a potential approach for the development of starch films with desirable properties. • Cellulose molecules were successfully cross-linked by boron ester bonds. • BNC exhibited higher relative crystallinity and thermal stability than NC. • Borax modification induced favorable dispersibility of BNC in starch film matrix. • BNC significantly enhanced the tensile strength and water resistance of CS films. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • The biopolymer-based from cassava starch (CS) and cellulose fiber (CF) from sugar cane leave was made by help of carboxylated styrene-butadiene rubber (CSBR) as an adhesion. • The addition of the cellulose fiber in the CSBR/CS blend exhibited higher in tensile strength compared to unfilled CF sample. • This study demonstrated a significant concentration of the CF improved the film properties. • The inexpensive biodegradable film was expected to be a promising candidate for alternative packaging materials. Abstract The biopolymer-based from cassava starch (CS) and cellulose fiber (CF) from sugar cane leaves was prepared by help of carboxylated styrene-butadiene rubber (CSBR) as an adhesion. The CF was isolated by using acid hydrolysis under heating (50 wt%, 140 °C for 2 h). The size, morphology, chemical structure, interaction bonding, dynamic mechanical behavior, thermal analysis, biodegradation, physical and mechanical performance of CSBR/CS/CF composites were investigated. The highest tensile value was found at 1.6 wt% CF loading (27.96 MPa) while preserving the large extent of their biodegradability (<80% after buried in soil for 30 days). Moreover, the increasing CF content led to decrease in the water contact angle, moisture content owing to the interfacial adhesion between carboxyl groups on the CSBR and hydroxyl groups on the CF surfaces. This study demonstrated a significant concentration of the CF on film properties. Moreover, these inexpensive biodegradable composites were preferable for packing, fruit container and paper coating applications. [ABSTRACT FROM AUTHOR]

An alumina enriched Al 2 O 3 -SiO 2 aerogel was successfully synthesized using an inexpensive inorganic aluminum salt Al(H 2 O) 9 (NO 3 ) 3 as the precursor and tetraethoxysilane (TEOS) as the framework reinforcing agent via a sol-gel process followed by ambient pressure drying. In order to show the enhanced effect of TEOS on aerogel, its structure and properties were detected by FESEM, TEM and BET. Furthermore, FTIR and Raman spectra were collected to explain the enhancement mechanism of TEOS to Al 2 O 3 -SiO 2 aerogel at the molecular level. The FTIR spectra showed that some Al O Si and Al O Si O Si O Al bonds gradually formed during the reinforcement process. These long Al O Si O Si O Al chains supported and strengthened the alcogel skeleton and effectively avoided potential shrinkage and cracking during the ambient pressure drying process. In addition, Raman spectra supported this conclusion by verifying that Al O Si and Si O Si bonds were present. Moreover, the Raman spectra indicated that with the increase of the Si/Al mole ratio from 0 to 3.0, the primary gel skeleton of Al O Al bonds was gradually transformed to Si O Si bonds. When the Si/Al mole ratio was greater 3.0, Si O Si bonds became the primary bonds in the final aerogel. [ABSTRACT FROM AUTHOR]

The effect of carbon black from Mao bamboo (MBCB) as a reinforcing agent in melamine urea formaldehyde (MUF) resin wood adhesive is evaluated in this work. The incorporation of MBCB improved the adhesion strength and decreased the heat resistance of adhesive and the formaldehyde emission from plywood. Compared with MUF resin filled with flour, the wet bonding strength of that filled with MBCB was increased by 22.02% (from 1.68 to 2.05 MPa), and the formaldehyde emission was decreased by 21.24% (from 1.158 to 0.912 mg·L−1). Unfortunately, with the increase in the substitution ratio of MBCB to flour, the pre-pressing performance of wood adhesives was reduced. The enthalpy was increased from 24.25 to 25.27 J·g−1. It is suggested that MBCB participated in the curing process of MUF resin, which makes the curing reaction of MUF resin easier. Overall, these findings offer new insights into exploiting the utilization of carbon black in wood adhesives. [Display omitted] • Carbon black from Mao bamboo as a novel reinforcing agent in wood adhesives. • Wood adhesives filled with carbon black with high bonding strength. • Carbon black from Mao bamboo is a potential alternative to wheat flour. [ABSTRACT FROM AUTHOR]

A series of novel polydimethylsiloxane (PDMS) composites were prepared using polyvinylsilsesquioxanes (PVS) as reinforcing agent by hydrolytic condensation in the presence of organotin catalyst for the first time. The cross-linked network, morphology, thermal behavior and mechanical properties of these novel PDMS composites were examined by attenuated total reflection infrared spectroscopy (ATR-IR), scanning electron microscope (SEM), thermogravimetric analysis (TGA) and universal tensile testing machine, respectively. Experimental results showed that both thermal and mechanical properties of the PDMS composites were improved greatly by adding PVS. The prominent improvements in thermal and mechanical properties were likely attributed to the reinforcing interaction of PDMS chains and formed particles resulted from PVS self-crosslink. Meanwhile, we also found that with the increment in loading PVS, the resistance to thermal degradation of the PDMS composites in nitrogen atmosphere was enhanced obviously, but their resistance to thermal oxidation in air was not improved apparently. The unobvious improvement in resistance to thermal oxidation of the novel composites was likely due to the catalysis of oxygen. [ABSTRACT FROM AUTHOR]

The effect of autohydrolysis (AH) temperature (165 °C, 195 °C, 225 °C) on the structure, purity, and recovery yield of the cellulose residue isolated after additional alkaline and bleaching steps from wheat straw, was investigated. The processes were quantified for mass yields in the different steps and for antioxidants and sugars release during AH. AH at 195 °C allowed for the highest cellulose residue yield (83.5%) with purity (∼70%) and structure similar to the other residues. FTIR and XRD analyses showed straw cellulose (SC) with a type II polymorphism and crystallinity index increasing with AH temperature. SC obtained at the end of the entire fractionation process (SC-195 °C) starting from AH residue-195 °C was tested as a reinforcing agent in different percentage (0, 2 and 5% by weight) in poly(butylene adipate- co -terephthalate) (PBAT) films. The Young's modulus of the films increased by ∼17% with 5 wt% cellulose, while tensile strength and elongation at break decreased. [Display omitted] • Investigation of autohydrolysis pretreatment for cellulose recovery from wheat straw • Effect of autohydrolysis on cellulose purity and structure • Cellulose from autohydrolysis tested as a reinforcing agent for PBAT films • Improvement of Young's module of PBAT films with cellulose [ABSTRACT FROM AUTHOR]

This study reports a new method of fabrication and application of "green" starch nanoparticles (SNPs) from local sago (Metroxylon Sagu) starch granules employing a high-pressure homogenization procedure. This approach is environmentally friendly, highly feasible, low cost and chemical-free with large-scale production capacity. In this work, SNPs' morphological, particle size and thermal properties were studied. The effects of SNPs concentration (ranging from 0 to 8% w/w) as nano-fillers in composite films' barrier, transparency and contact angle were also investigated. Our results have shown that the fabricated SNPs exhibited excellent uniformity and spherical shapes. Addition of SNPs have demonstrated to enhance polymeric structure of nanocomposite film due to decreased water vapour permeability and increased contact angle. Sago SNPs as fillers pose an excellent prospect in green composites fabrication for material and biomedical purposes with potential application as carriers for drug delivery. Image 1 • Green sago starch nanoparticles were developed using high pressure homogenization. • Sago starch nanoparticles was shown to bring about stronger reinforcing effect. • Nanocomposites showed improved water vapour permeability and contact angle. [ABSTRACT FROM AUTHOR]

The water-soluble sand cores (WSC-sand) used in the investment casting of complex three-dimensional metal parts are highly susceptible to casting defects. Our objective in this study was to optimize the fabrication process for a novel high-strength WSC-sand comprising magnesium sulfate (MgSO 4) composite, based on thermodynamic analysis using a thermochemistry software package (FactSage) and experimental verification. Preliminary analyses and experiments were used to derive the optimal preparation conditions for high-strength WSC-sand-MG: raw sand (equal weights of magnesia oxide and graphite), binder (2 wt% MgSO 4 at a concentration of 30%), and heating temperature (200 °C). Subsequent experiments revealed that the optimal quantity of reinforcing agent (RA) (kaolinite) was 2 wt%. The efficacy of the fabrication process was validated by creating metal casts (SNCM220 at a casting temperature of 1600 °C) using two types of WSC-sand-MG-RA samples. Nondestructive radiographic testing images and photographs of the finished casting products verified the efficacy of the proposed fabrication strategy in terms of surface smoothness and inside pinholes. The results presented in this paper provide a valuable reference for the preparation of WSC-sand from the perspective of quality and cost efficiency. Unlabelled Image • A new ingredient-formula of water-soluble sand core (WSC-sand) was proposed. • By thermodynamic analysis, Mg(OH) 2 may also enhance the strength of WSC-sand. • The proposed WSC-sand can resist thermal impact and produce little gas during casting. • RT images of the finished casting products verified the efficacy of proposed WSC-sand. [ABSTRACT FROM AUTHOR]