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Copyright of Industrial Minerals & Processing / Huagong Kuangwu yu Jiagong is the property of Industrial Minerals & Processing Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

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]

Lignin-cellulose nanocrystals (L-CNCs) can be used as UV-functional fillers in polyvinyl alcohol (PVA) films for various applications. However, agglomeration of particles restricts their addition to 20 wt% in the polymer matrix due to the reduction in mechanical properties. In this work, a new method is proposed to produce a flexible UV-protective composite film with a superior amount of L-CNCs (>76 wt%), where cellulose nanocrystals (CNCs) were used as a co-reinforcing agent (20%) and amount of synthetic polymer was very low, i.e., 5% PVA. Hemp hurd, a naturally abundant waste resource, was used for both L-CNCs and CNCs extraction. The addition of CNCs showed a synergistic effect with L-CNCs, improving the UV-shielding ability of the film at 300–400 nm light wavelength. The resultant films were flexible, and showed similar elongation behaviour to PVA, yet had a high modulus. The initial results showed improvement in the shelf-life of raspberries with a high amount of L-CNCs film, which indicated the potential of the bio-based nanocomposite film as a sustainable alternative to commercial petroleum-based plastics.

The main aspects of strengthening aluminium alloys with zirconium are considered in detail in this work. As established, the improvement of the mechanical properties of aluminium alloys with zirconium occurs not only due to the grinding of the grains of the solution of the main alloying component in aluminium, but also by the refining effect of zirconium that is purifying the aluminium alloys from hydrogen. In addition, the strengthening of aluminium alloys with zirconium is achieved by preventing the appearance of undesirable brittle phases, for example, Mg2Al3, Mg5Al8, in alloys of the Al- Mg system that is achieved by the injection of zirconium. [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.

A highly transparent sole rubber was prepared by cis-butadiene rubber and dissolved polystyrene-butadiene rubber as the materials, fumed silica as the reinforcing agent, coupling agent and vulcanizing agent. The effects of coupling agent types and fumed silica on the rubber properties were studied. The results show that the optimal conditions for the preparation of highly transparent sole rubber are to choose a mixture of BH-8172 with different molecular weights of vinyl modified silane as the coupling agent, and 20 phr of gas-phase silica HL-200 as the reinforcing agent, whose light transmittance is 80.7%, the tensile strength is 11.0 MPa, the elongation at break is 433%, the hardness of Shore is 68A, and the relative wear volume is 98mm³. [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]

Valorisation of industrial biomass wastes, such as oil palm empty fruit bunch (EFB) generated by the palm oil industry, could promote its sustainable use while minimising the adverse impacts on the environment. To this end, the present study attempted to synthesize lignin from EFB. A simple yet environmentally friendly technique, ultrasonication, has been employed to convert the isolated lignin to lignin nanoparticles (LNPs). The transmission electron microscopy results and dynamic light scattering measurements have confirmed the mean particle size of LNPs at 220 nm. Also, LNPs showed better thermal performance compared to lignin, as indicated by a higher glass transition and maximum degradation temperature. LNPs were stable in the pH range of 4.5 - 9.0 and sodium chloride concentration below 100 mM over a week of storage. At pH 7, the LNP suspension remains stable without precipitation for up to three months of storage under ambient conditions. In addition, the LNPs were incorporated into the starch matrix to form biocomposites and then compared against lignin biocomposites and neat starch film for their thermal, mechanical, and hydrophobic performance. The biocomposites with LNPs are anticipatedly possessing better performance than the neat starch film and lignin biocomposites in all aspects.

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]

The fire in mine goaf directly threatens the safe and efficient production of mining. Filling the air leakage channel in goaf is the most effective way to prevent spontaneous combustion of coal in goaf. In this paper, the effects of accelerators and foaming agents on the strength of inorganic foaming paste filling materials were discussed, and the mechanism of the reinforcing agents was analyzed. The results show that the inorganic solidified foam material has faster solidification with the increase of the amount of quick-setting admixture; the compressive strength of the filling material with a foaming ratio of 10 is above 1.7 MPa after curing for 7 days; the large number of bubbles existing in the material form numerous uniform defects, and the reinforcing agent causes the aluminum-oxygen component in the paste slurry to react with the cement component on a large scale and quickly to form an excellent hydrated mineral ettringite, so that the overall structure of the material does not change when the material is stressed, and no crack occurs in the middle portion, and the material effectively blocks the cracks in the fire zone and isolate oxygen to prevent fires in the goaf.

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]

Purpose: This paper presents a comprehensive review of nanocellulose and its application in several applications, including composites, biomedical, and food packaging fields. Design/methodology/approach: General explanations about cellulose and nanocellulose have been described. Different types of nanocellulose (cellulose nanofibers, cellulose nanocrystals, bacterial nanocellulose) as well as their isolation processes (mechanical process, chemical process) have been reviewed. Several surface modifications have been explained to improve the dispersion of nanocellulose in non-polar polymers. The possible utilization of nanocellulose in composites, biomedical, and food packaging fields have also been analysed. Findings: This review presents three application fields at once, namely composites, biomedical, and food packaging fields. In the composite field, nanocellulose can be used as a reinforcing agent which increases the mehcnical properties such as tensile strength and toughness, and thermal stability of the final composites. In the biomedical field, nanocellulose is reinforced into hydrogel or composites which will be produced as tissue scaffolding, wound dressing, etc. It is found that the addition of nanocellulose can extend and control the drug release. While in the packaging field, nanocellulose is added into a biopolymer to improve the barrier properties and decrease the water and oxygen vapor transmission rates. Research limitations/implications: Nanocellulose has a hydrophilic nature, thus making it agglomerated and difficult to disperse in most non-polar polymers. Therefore, certain surface modification of nanocellulose are required prior to the preparation of composites or hydrogels. Practical implications: Further research regarding the toxicity of nanocellulose needs to be investigated, especially when applying it in the biomedical and food packaging fields. Originality/value: This review presents three application fields at once, namely composites, biomedical, and food packaging fields. [ABSTRACT FROM AUTHOR]

Poly(N-vinyl pyrrolidone) (PNVP) is one of the most studied and recognized polymer for use in the pharmaceutical industry and medicine purposes due to its unique combination of highly essential properties such as nontoxicity, biocompatibility with human tissue, chemical stability, and good solubility in water and other solvents. Most of the PNVP-based hydrogels are characterized by low mechanical properties when handled in a swollen state. For this purpose, several methods have been reported to increase the mechanical properties of these gels by introducing an inorganic clay as a reinforcing agent. The present work deals with the preparation and detailed structural characterization of nanocomposite hydrogels based on amidic N-vinyl pyrrolidone (NVP) monomers with or without N,N-methylenbis(acrylamide) (MBA) as chemical crosslinker and different concentrations of Laponite XLG as reinforcing agent. The hydrogels were synthesized by the radical polymerization of the monomers using 2,2-azobisisobutyronitrile (AIBN) as the initiator. In this study, we evaluated the structure of PNVP-based nanocomposites by using FT-IR, their morphology through SEM–EDX, and the influence of different amounts of Laponite XLG on the final properties, by performing rheological measurements and swelling studies. The Laponite XLG, used as reinforcing agent, significantly contributed to the improvement in the mechanical properties of the nanocomposite hydrogels.

Point-Q reinforcing agent, recycled glass material, calcium carbonate powder and styrene-acrylic emulsion are used in the ternary cementitious material system to modify and strengthen the polymer cement waterproof mortar. The experimental results show that when the proportion of added Sulphoaluminate cement, the addition of reinforcing agent, the cement-sand ratio, the mass ratio of emulsion to powder and the ambient temperature are at values of 26%,1.0%,1:1,1:3 and 0-40 111,the strength, viscosity, setting time and impermeable pressure of the new polymer modified waterproof mortar reach a higher level than before, filling that defects of poor adhesion and low strength caused by the smooth surface of the recycled glass material when it's used in the waterproof mortar. [ABSTRACT FROM AUTHOR]

Copyright of Bulletin of the Chinese Ceramic Society is the property of Bulletin of the Chinese Ceramic Society Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

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.

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]

The brittleness of ethyl cellulose (EC) film limited its full applications, and the addition of plasticizers is one of the most common methods to reduce its brittleness. However, the mechanical properties are normally dropped with the addition of plasticizers. Herein, cellulose nanocrystal (CNC) was chosen as a reinforcing agent to improve its mechanical properties. CNC was firstly extracted from the tobacco-stem and then modified by epoxidized soybean oil (ESO) via ring-opening grafting to obtain epoxidized soybean oil grafting CNC (ECNC). The grafting effect was evaluated by FTIR and XPS. After that, the films of ECNC/EC nanocomposites were prepared by the solution-casting method, and their mechanical, thermal and optical properties and fracture morphology were investigated. The results showed that at 4 phr loading of ECNC, the tensile strength of the nanocomposite film was up to 43.7 Mpa (about twice as much as that of the EC film plasticized by ESO), and the elongation at break was not influenced. Moreover, a higher thermal decomposition temperature was achieved for the ECNC/EC films. Besides, owing to the good dispersion, ECNC had no significant impact on the transparency, and the films presented high light transmittance in the visible light region. [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]

Copyright of Clean Coal Technology is the property of Clean Coal Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The effect of sulfated (original), carboxylated (oxidized), and Jeffamines M2005‐grafted cellulose nanocrystals (CNCs) on the barrier and mechanical properties of thermoplastic starch (TPS) and poly(3‐hydroxybutyrate) (P(3HB)) matrices was investigated. CNCs were first oxidized via a catalytic reaction using NaClO as an oxidant and then grafted with an amine‐terminated ethylene oxide (EO)/propylene oxide (PO) copolymer (Jeffamine) by an amine‐acid coupling reaction. A degree of oxidation (DO) of 0.108 (mol/mol of anhydroglucose) was attempted for the carboxylated CNCs, whereas a degree of substitution (DS) of 0.04 (mol/mol of anhydroglucose) was determined for the M2005‐grafted CNCs. These values indicated satisfactory reactive process, with yields of 68% and 47.3% for the carboxylation and peptide coupling reactions, respectively. Fourier‐transform infrared spectroscopy (FTIR) analysis showed bands at 1643 cm−1 and 1550 cm−1 in the spectrum of M2005‐grafted CNCs, which qualitatively indicated the amide bond formation. In addition, the morphology and the zeta potential of modified CNCs ensured their homogeneity, stability, and surface degree of charge. In spite of a decrease in the solubility in water of the modified crystals, the procedure of chemical modification used avoided any variation in their crystalline structure and thermal stability. Then, the incorporation of sulfated, oxidized, or M2005‐grafted CNCs in matrices of TPS and P(3HB) allowed to produce reinforced nanocomposite films, with excellent barrier properties. Therefore, the chemical compatibility between CNCs and the polymer matrices is essential to produce attractive nanocomposites with improved mechanical properties for industrial applications. [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.

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 worldwide trend toward using cheap, atoxic and durable materials from renewable resources contributes to sustainable development. Thus, the investigation of the potential use of vegetal fibers as reinforcing agent in polymeric composites has gained new significance. Sisal fiber has emerged as a reinforcing material for polymers used in automobile, footwear and civil industries. In this work, properties such as hardness, tensile strength and tear strength of polymer composites composed by block copolymer styrene-butadiene-styrene (SBS) and 5, 10 and 20% by weight of sisal fiber were evaluated. The influence of conventional polymer processing techniques such as single-screw and double-screw extrusion, as well as the addition of coupling agent on the composite mechanical performance was investigated. Also, the morphology and thermal stability of the composites were analyzed. The addition of 2 wt. (%) maleic anhydride as coupling agent between sisal fiber and SBS has improved the composite mechanical performance and the processing in a double-screw extruder has favored the sisal fiber distribution in the SBS matrix.

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]

In order to investigate the effects of binder component on the creep properties of polymer-bonded explosive (PBX), three-point bending creep behaviors of 1,3,5-triamino-2,4,6-trinitrobenzene (TATB)-based PBX and its styrene copolymer modified formulation were studied by dynamic mechanical analyzer. The experimental results showed that owing to the addition of reinforcing agent (styrene copolymer) with high glass transition temperature and high mechanical strength, the creep resistance performance of the modified formulation was improved with reduced creep strain and constant creep rate and prolonged creep failure time. A six-element mechanical model was applied to simulate the creep behaviors of TATB-based PBX and its modified formulation. The constitutive equation of creep curves under different conditions were obtained by nonlinear fit. The predicted theoretical results coincided quite well with the experimental data. [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]

For preventing and extinguishing the spontaneous combustion of coal seam, based on the importance for sealing air leakage channels in roadway, developed a material of light-paste for coalmine, and research its ingredient, proportion and performance. The result indicates that the component ratio of the material is which PB exciting agent is 20%, complex reinforcing agent is 2%, complex expansion agent is 1%, and A-material is 77%. The performances of compressive strength, swelling ratio and expansion time are optimum. The light-paste material can effectively seal air leakage channels for preventing and extinguishing the spontaneous combustion of coal seam in coalmine. [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]

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]

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]