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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]

In this study, Typha latifolia (Typha sp.) was investigated as a new raw material for the isolation of cellulose nanocrystals (CNCs) for future application in geopolymer cement. Cellulose was extracted from the stem fibers by carrying out alkali and bleaching treatments. CNCs were then isolated from the extracted cellulose using the acid hydrolysis method. The chemical composition of cellulose, hemicellulose, and lignin was 60.9%, 7.0%, and 5.7%, respectively. Transmission electron microscopy showed a reduction in particle size due to the loss of the amorphous portion of the Typha sp. fiber. Thermogravimetric analysis showed that CNCs in the acid hydrolysis treatment have good thermal stability at 240 °C which is higher than raw ones. Based on the characteristics of a Typha sp. CNCs, it can be concluded that CNCs have the potential to be used as a reinforcement in geopolymer cement. [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]

Modification of cellulose fibers is a promissory alternative for the production of new composite materials, but the high hydrophilicity of cellulose limits its use as a reinforcing agent in the making of olefin-based composites. The aim of this research was to develop reinforcing agents based on cellulose fibers modified by insertion of end-alkyl groups from pyrolytic bio-oil (PBO). For that, PBO of sugarcane bagasse was obtained and characterized by several techniques including gas chromatography coupled to mass spectrometry. Later, the surface of cellulose fibers was activated using methylene-bis-isocyanate and modified using acetic acid, formic acid, and PBO. Results show that the modification of cellulose surface is possible by the use of PBO at low temperature obtaining results like to those obtained when organic acids are used. [ABSTRACT FROM AUTHOR]

Dental ceramics made from Yttria stabilized tetragonal Zirconia polycrystalline (Y-TZP) with feldspathic porcelain veneers have similar mechanical and aesthetic response to natural tooth. However, cases of early failure, such as chipping or fracture in the veneering have been reported after short periods of use. The present study evaluated the feldspathic porcelain (VITA-VM9) with addition of 0.5 and 2.5 wt% Alumina-Zirconia as reinforcing agents. Hardness, fracture toughness, contact resistance and color variations were evaluated finding better mechanical performance on the new formulations. [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]

The paper studies the behavior of ceramic porous tungsten alloy with reinforcing agents under the shock-wave loading conditions. Penetrating capacity of tungsten kinetic energy projectiles is calculated and experimentally investigated during their high-speed impacts on steel plates. It is shown that the increased penetration depth of tungsten projectiles exceeds that of the prototype with relevant weight and size, made of tungsten-nickel-iron cast alloy. A mathematical model is developed together with the design technique of the behavior of tungstennickel-iron-cobalt metal foams alloyed with boron carbide, tungsten titanium carbide and tungsten carbide during the high-speed impact interaction. The composite ceramic material is described here as a porous medium. The matrix of this medium is a homogeneous two-phase mixture of the tungsten-nickel-iron-cobalt system and reinforcing agents added in the required proportions. [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 purpose of this study was to investigate a popular reinforcing agent in the papermaking industry through a quick, environmentally friendly, microwave-assisted method. The preparation and characterization of cellulose-CaCO3 composites through this route, in a mixed solution of an ionic liquid and ethylene glycol, can occur within a 10-min timeframe. The chemical compounds, calcium acetate and sodium carbonate, were used as reactants for the as-obtained CaCO3 crystals. A NaOH-urea aqueous solution was used to treat the cellulose and prepare cellulose- CaCO3 composites. It was discovered that the addition of ionic liquids favors the preparation of cellulose-CaCO3 composites. [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]

At ambient atmospheric condition copper nanoparticles (CuNPs) were prepared in aqueous medium using copper chloride, sodium borohydride, ascorbic acid and polyvinyl alcohol (PVA) of two different molecular weights ( Ms). The physical appearance of the prepared sol of CuNPs has been found to be stable for a couple of weeks when kept in ambient atmospheric condition, as confirmed by ultraviolet-visible absorption spectroscopy. Transmission electron microscopy exhibits spherical morphology of CuNPs with an average size of 3.5 ± 1.1 nm developed in the sol, where PVA of high M renders smaller size (2.5 nm) than that of low M. The synthesised CuNPs were embedded in palm oil fibres (POFs) via cationisation process. The cationisation of POF was ascertained by Fourier-transformed infrared and zero point charge determination. The inclusion of nanoparticles (NPs) onto the fibres' surface has been consistently proven by Fourier transformed infrared spectroscopy, X-ray diffraction study, field emission scanning electron microscopy, energy dispersive X-ray study and thermogravimetric analysis. CuNP-coated POF showed the increment of tensile strength (∼34 %) and antifungal activity (24 %) with respect to control fibres. The observed findings suggest that NPs can be effectively used as reinforcing agents in natural fibres to improve their property and durability. [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]

Mango seeds are lignocellulosic agro-industrial residues available in large quantities in tropical countries and are simply discarded or used as animal feed. They are a natural and renewable resource, and were used to generate new polymeric materials in this work. This new materials can be used as alternatives to fossil resources such as petroleum. This work aimed to extract and characterize cellulose nanocrystals (CN) from mango seed by acid hydrolysis to obtain a material suitable as a reinforcing agent in the manufacturing of nanocomposites. The fibers of mango seeds were ground in mills and purified mainly to remove lignin. The raw mango seed (MS) and the purified mango seed (PMS) were analyzed for chemical composition and characterized by infrared and X-rays. Cellulose nanocrystals from the mango seed (CNM) were isolated by acid hydrolysis at 40 °C for 10 min, with 20 ml of H2SO4 (11.21 M) used for every gram of cellulose. The yield at this step was 22.8%. CNM were needle-shaped, with high crystallinity (90.6%), good thermal stability (around 248 °C), a medium length (L) of 123.4 ± 22.1 nm and a diameter (D) of 4.59 ± 2.22 nm, giving an aspect ratio (L/D) of about 34.1 ± 18.6. The diameter measurements of CNM were also confirmed by Scherrer's equation. This work also aimed to reuse mango seed produced as industrial waste, giving it a useful application and preventing its role as an environmental pollutant. [Copyright &y& Elsevier]

According to the relevant literature, the utilization of different kind of glass fibers in concrete introduces positive effect on the mechanical behavior, especially toughness. There are many glass fibers available to reinforce concretes. Glass fiber composition is so important because it may change the properties such as strength, elastic modulus and alkali resistance. Its most important property to be used in concrete is the alkali resistance. Some glasses of SrO-MgO-ZrO2-SiO2 (SMZS) quaternary system, such as 26SrO, 20MgO, 14ZrO2, 40SiO2 (Zrn glass), have been found to be highly alkali resistant thanks to their high ZrO2 and MgO contents. Previous researches on these glasses with MnO and/or Fe2O3 partially replacing SrO have been made with the aim of improving the chemical resistance and decreasing the production cost. The main target of the present study, first of all, was to characterize commercially available alkali resistant glass fiber for concrete reinforcement and then to compare its alkali durability with those of the SrO-Mn2O3-Fe2O3-MgO-ZrO2-SiO2 (SMFMZS) system glasses. For such purposes, XRF, Tg-DTA, alkali resistance tests and SEM analysis conducted with EDX were employed. According to the alkali endurance test results it was revealed that some of the SMFMZS system glass powders are 10 times resistant to alkali environments than the commercial glass fibers used in this study. Therefore, they can be considered as alternative filling materials on the evolution of chemically resistant concrete structures. [ABSTRACT FROM AUTHOR]

In this study the feasibility of applying two kinds of mudar (Calotropis gigantea) fibers, namely bark fibers and seed fibers, as an alternative raw material for fiber-reinforced composite (FRC) is investigated. The chemical analysis of the bark and seed fibers indicates that their main components are holocellulose 76 and 69%, cellulose 57 and 49%, lignin 18 and 23%, and alkali soluble substances 17 and 15%, respectively. There are statistically significant differences in the bark and seed fiber dimensions. The bark fibers are long, with a thin wall relative to their diameter, and are therefore lightweight. The seed and bark fibers are very similar to hard- and soft-woods, in terms of chemical compositions and fiber dimensions, respectively. The mechanical properties of the mudar bark fibers are: tensile strength 381 MPa, strain at break 2.1% and Young's modulus 9.7 GPa. In general, both types of fibers have enough potential for replacing or supplementing other fibrous raw materials as reinforcing agent. [ABSTRACT FROM AUTHOR]

In this work, poly(lactic acid) (PLA)/gelatin/PLA multilayer films supplemented with cellulose nanocrystals and antioxidant extract from almond shell (AS) by-products were developed by solvent casting technique for active food packaging. The almond shell antioxidant extract (ASE) was obtained by microwave-assisted extraction, while cellulose nanocrystals (CNCs) were extracted from AS by a sequential process of alkalization, acetylation and acid hydrolysis. Four formulations were obtained by adding 0 (control), 6 wt.% of ASE (FG/ASE), 4.5 wt.% of CNCs (FG/CNC) and 6 wt.% + 4.5 wt.% of ASE + CNCs, respectively, (FG/ASE + CNC) into fish gelatin (FG). PLA/FG/PLA multilayer films were prepared by stacking two outer PLA layers into a middle FG film. A surface modification of PLA by air atmospheric plasma treatment was optimized before multilayer development to improve PLA adhesion. Complete characterization of the multilayers underlined the FG/ASE + CNC formulation as a promising active reinforced packaging system for food preservation, with low values of transparency, lightness and whiteness index. A good adhesion and homogeneity of the multilayer system was obtained by SEM, and they also demonstrated low oxygen permeability (40.87 ± 5.20 cm3 mm m−2 day) and solubility (39.19 ± 0.16%) values, while mechanical properties were comparable with commercial plastic films. The developed multilayer films were applied to Hass avocado preservation. The initial degradation temperature (Tini), DSC parameters and in vitro antioxidant capacity of the films were in accordance with the low peroxide and anisidine values obtained from avocado pulp after packaging for 14 days at 4 °C. The developed PLA/FG/PLA films supplemented with 6 wt.% ASE+ 4.5 wt.% CNCs may be potential bioactive packaging systems for fat food preservation. [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]

More than 10 million tons of textile waste are disposed through landfill every year in North America. The disposal of textile waste via landfill or incineration causes environmental problems and represents a waste of useful resources. In this work, we explored the possibility to directly extract cellulose nanocrystals (CNCs) from untreated textile waste through two methods, namely sulfuric acid hydrolysis and three-step oxidization. CNCs with cellulose Iβ crystalline structure and rod-like shape were successfully obtained. The aspect ratios of CNCs prepared from acid hydrolysis and oxidization were 10.00 ± 3.39 and 17.10 ± 12.85, respectively. Their application as reinforcing agent of soybean protein isolate (SPI) film was evaluated. With the addition of 20% CNCs, the composite film maintained the high transparency, while their water vapor barrier property, tensile strength, and Young's modulus were significantly improved. This research demonstrates a promising approach to recycle textile waste, and more value-added applications based on the derived CNCs could be expected. [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]

Potassium hexatitanate (PHT) with chemical formula K2Ti6O13 has a tunnel structure formed by TiO2 octahedra sharing edges or corners and with the potassium atoms located in the tunnels. This material has attracted great interest in the areas of photocatalysis, reinforcement of materials, biomaterials, etc. This work summarizes a large number of studies about methods to prepare PHT since particle size can be modified from millimeter to nanometric scale according to the applied method. Likewise, the synthesis method has influenced the material properties as band-gap and the final mechanical performance of composites when the reinforcement is PHT. The knowing of synthesis, properties and applications of PHT is worthwhile for the design of new materials and for the development of new applications taking advantage of their inherent properties. [ABSTRACT FROM AUTHOR]