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Highlights As is well known, Laser print paper is usually produced with high‐quality chemical wood pulp. The laser print waste paper fiber (LPWF) is a high‐quality secondary fiber, and the research and development of high‐value utilization technology for laser print waste paper has attracted much attention in the field of renewable resource recycling. In this study, LPWF was used to reinforce poly(lactic acid) (PLA) composites in the field, and the composites were modified with bioenzyme, cationic polyacrylamide (CPAM), and nano‐silicon carbide (Nano‐SiC) to enhance the interfacial compatibility of LPWF/PLA composites. The study systematically investigated the effects of various modification methods on the characteristics and degradability of composites made from laser print waste paper fiber reinforced PLA resin matrix. The results showed that the mechanical properties of the composites treated with CPAM and Nano‐SiC were significantly improved, with tensile strengths of 54.3 and 59.5 MPa, and flexural strengths of 85.1 and 91.5 MPa, respectively, and the water absorption of the composites was reduced after the modification treatment, while the thermal stability was improved. The degradation performance of the composites in various water environments indicated that the inclusion of LPWF accelerated the water degradation rate of the composites, with the maximum degradation rate of the composite reaching 1.26% in 30 days. Laser print waste paper is an excellent quality recyclable fiber resource. Four modifiers were used to modify LPWF/PLA composites. Characteristics and degradability of the composites were investigated. Significantly improved properties of CPAM and Nano‐SiC modified composites. The degradation rate of composites is increased by the addition of LPWF. [ABSTRACT FROM AUTHOR]

Bamboo fibers ( BFs ), with features of renewability and biodegradability, have been widely used in paper-making products. In order to improve the mechanical properties and water absorption behaviors of the BF paper, bacterial cellulose nanofibers ( BCNFs) as environmentally friendly nano-fibrillated cellulose ( NFC) were combined with BFs. The structures and properties of the BF/ BCNF composite paper were characterized by field emission scanning electron microscopy (FE-SEM), X-ray diffraction (XRD), Fourier transforms infrared(FTIR) spectroscopy, mechanical tests, pore size tests, and water absorption tests. The results indicated that the addition of BCNFs could significantly improve the water absorption capacity and mechanical properties. The water absorption ratio of the BF/ BCNF composite paper with a BCNF mass fraction of 9% comes to 443%, about 1. 33 times that of the pure BF paper. At the same BCNF content, the tensile strength of the BF/ BCNF composite paper in dry and wet states was 12. 37 MPa and 200. 9 kPa, respectively, increasing by 98. 24% and 136. 91% as compared with that of the BF paper. [ABSTRACT FROM AUTHOR]

The microcrystalline cellulose/thermoplastic starch (MCC/TPS) film was prepared by melt extrusion method, and the MCC/TPS film was combined with paper by hot pressing method. The results show that the SEM images show that the interface layer of paper-plastic composite has good adhesion. When the addition a-mount of MCC is 5wt%, the mechanical properties of TPS film are improved, and the path of water vapor through TPS film is extended, resulting in the water vapor transmittability of MCC/TPS/paper composite is reduced, and the barrier properties of paper-plastic composite are improved. TPS/paper composites and MCC/ TPS/paper composites have better physical properties (i.e. smoothness, flexibility and folding resistance) than paper alone. Therefore, the addition of MCC can improve the barrier properties and mechanical properties of paper-plastic composite materials to meet the requirements of the food packaging industry for low water sensitive materials. [ABSTRACT FROM AUTHOR]

Different phenolic resins have a direct impact on the properties of aramid paper honeycombs. It is important to study the relationship between phenolic resin and honeycomb properties. Two different phenolic resins are used to prepare aramid paper honeycomb core materials, and the compression properties, shear properties, flame retardancy and dielectric properties of the prepared honeycomb core material are tested. Combining the observation of resin end face resin distribution and contact angle measurement, the reasons for the difference in performance of honeycomb core materials prepared by two kinds of resins are analyzed. The results show that the temperature resistance of the resin itself directly affects the temperature resistance of the honeycomb and the volatilization rate of solvent water in the resin and the surface tension between the resin and the aramid paper affect the resin distribution of the resin on the honeycomb wall. When the content of the honeycomb core resin is the same, the resin rubber column at the end of the joint is beneficial to increase the compressive strength of the honeycomb core material, but the accumulation of the resin at the end of the node reduces the wall thickness of the honeycomb, resulting in a decrease in the shear strength and modulus of the honeycomb.

BACKGROUND: Different thermoplastic starch (TPS) films were prepared with or without the addition of microcrystalline cellulose (MCC) obtained via the melt‐extrusion method, and then the hot‐press method was used to produce environmentally friendly TPS‐based film/paper composites to replace petroleum‐based materials. RESULTS: The paper–plastic composites exhibited good interfacial adhesion from the scannign elctron microscopy images. It was seen that 5 wt.% MCC was added to reinforce the mechanical properties of TPS films, such that it also improved the barrier properties of MCC@TPS/paper composites and extended the path of water vapor through TPS films, which decreased the water vapor transmission rate of MCC@TPS/paper composites. TPS/paper composites and MCC@TPS/paper composites have better physical properties (i.e. smoothness, flexibility and folding resistance) than only paper. In particular, it was found that the water contact angle of MCC@TPS/paper composites and TPS/paper composites were higher than single‐layer paper. Furthermore, MCC reinforced paper–plastic composites demonstrated good barrier properties which can meet the requirement of the need for lower water sensitive materials in the food packaging industry. CONCLUSION: Thermoplastic corn starch‐based film/paper composites have good application properties as a potential source of bioplastic materials. © 2021 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

With the aim of exploring an alternative method of nano-doping in cellulose paper and improving flashover strength of oil-impregnated paper, radio frequency (RF) magnetron sputtering method is introduced into the structural modification of insulating paper for converter transformers. In this experiment, insulating paper was treated with ZnO sputtering for 0, 7.5, 15 and 30 min, respectively. The surface morphology of dry paper was observed with a scanning electron microscope. The bonding mode of sputtered ZnO particles with cellulose matrix was investigated via attenuated total reflection infrared (ATR-IR) spectroscopy and mechanical property of the sputtered samples were studied. Surface and volume conductivities of the oil-impregnated sputtered paper were measured. Moreover, the charge dissipation characteristics of sputtered insulating paper was investigated by means of surface potential decay. In addition, trap distribution and carrier mobility of specimen were further obtained. Finally, the DC flashover strength were tested. The results showed that ZnO magnetron sputtering had a distinct influence on the structure of the insulating paper, resulting in the formation of hydrogen bond and chemical bond and an increase of the surface and volume conductivities. ZnO sputtering was found to decrease the initial potential and accelerate charge decay. Moreover, appropriate sputtering enhanced the surface flashover strength.

Abstract As the rapid development of portable and wearable devices, different electromagnetic interference (EMI) shielding materials with high efficiency have been desired to eliminate the resulting radiation pollution. However, limited EMI shielding materials are successfully used in practical applications, due to the heavy thickness and absence of sufficient strength or flexibility. Herein, an ultrathin and flexible carbon nanotubes/MXene/cellulose nanofibrils composite paper with gradient and sandwich structure is constructed for EMI shielding application via a facile alternating vacuum-assisted filtration process. The composite paper exhibits outstanding mechanical properties with a tensile strength of 97.9 ± 5.0 MPa and a fracture strain of 4.6 ± 0.2%. Particularly, the paper shows a high electrical conductivity of 2506.6 S m−1 and EMI shielding effectiveness (EMI SE) of 38.4 dB due to the sandwich structure in improving EMI SE, and the gradient structure on regulating the contributions from reflection and absorption. This strategy is of great significance in fabricating ultrathin and flexible composite paper for highly efficient EMI shielding performance and in broadening the practical applications of MXene-based composite materials.

In this study, continuous carbon reinforced C f /(Ti 0.2 Zr 0.2 Hf 0.2 Nb 0.2 Ta 0.2)C–SiC high entropy ceramic matrix composites were additively manufactured through paper laminating (PL), direct slurry writing (DSW), and precursor infiltration and pyrolysis (PIP). (Ti 0.2 Zr 0.2 Hf 0.2 Nb 0.2 Ta 0.2)C high entropy ceramic (HEC) powders were synthesized by pressureless sintering and ball milling. A certain proportion of HEC powder, SiC powder, water, binder, and dispersant were mixed to prepare the HEC-SiC slurry. Meanwhile, BN coating was prepared on the 2D fiber cloth surface by the boric acid-urea method and then the cloth was cut into required shape. Additive manufacturing were conducted subsequently. Firstly, one piece of the as-treated carbon fiber cloth was auto-placed on the workbench by paper laminating (PL). Then, the HEC-SiC slurry was extruded onto the surface of the cloth by direct slurry writing (DSW). PL and DSW process were repeated, and a C f /HEC-SiC preform was obtained after 3 cycles. At last, the preform was densified by precursor infiltration and pyrolysis (PIP) and the final C f /HEC-SiC composite was prepared. The open porosity of the C f /HEC-SiC composites, with the HEC volume fractions of 15, 30 and 45%, were 7.7, 10.6, and 11.3%, respectively. And the density of the C f /HEC-SiC composites, with the HEC volume fractions of 15, 30 and 45%, were 2.9, 2.7 and 2.3 g/cm3, respectively. The mechanical properties of the C f /HEC-SiC composites increased firstly and then decreased with the HEC content increase, reaching the maximum value when the HEC volume fraction was 30%. The mechanical properties of the C f /HEC-SiC composites containing 45, 30 and 15% HEC were as follows: flexural strength (180.4 ± 14 MPa, 183.7 ± 4 MPa, and 173.9 ± 4 MPa), fracture toughness (11.9 ± 0.17 MPa m1/2, 14.6 ± 2.89 MPa m1/2, and 11.3 ± 1.88 MPa m1/2), and tensile strength (71.5 ± 4.9 MPa, 98.4 ± 12.2 MPa, and 73.4 ± 8.5 MPa). From this study, the additive manufacturing of continuous carbon fiber reinforced high entropy ceramic matrix composites was achieved, opening a new insight into the manufacturing of ceramic matrix composites. [ABSTRACT FROM AUTHOR]

Through natural selection, many animal organs with similar functions have evolved different macroscopic morphologies and microscopic structures. Here, we comparatively investigate the structures, properties and functions of honey bee stings and paper wasp stings. Their elegant structures were systematically observed. To examine their behaviors of penetrating into different materials, we performed penetration–extraction tests and slow motion analyses of their insertion process. In comparison, the barbed stings of honey bees are relatively difficult to be withdrawn from fibrous tissues (e.g. skin), while the removal of paper wasp stings is easier due to their different structures and insertion skills. The similarities and differences of the two kinds of stings are summarized on the basis of the experiments and observations.

Copyright of Journal of Wildland Fire Science is the property of Journal of Wildland Fire Science 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.)

Copyright of New Building Materials / Xinxing Jianzhu Cailiao is the property of New Building Materials 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.)

The filter paper of automobile engine air filter is easy to temper and causes combustion. Flame retardant is usually added to the reinforced resin styrene-acrylic emulsion (SAE) to improve the flame-retardant performance of the air filter paper. Ammonium polyphosphate (APP) was used as material in this research, and multi-layer coated APP was prepared by microcapsule coating. A layer of nano-scale SiO2 was coated and then introduced organosiloxane structure of the allyl polyoxypropylene ether side chain and boron. The chemical groups and structural composition were determined by Fourier transform infrared spectroscopy. TGA characterized the modified particles' high-temperature stability. By scanning electron microscopy and TEM, the morphologies of modified particles were analyzed to reveal the evolution of modified APP in SAE. Finally, nanoparticles with core-shell structures were formed. Applying the blended resin to the air filter paper, the flame-retardant performance was greatly improved. Total heat release (THR), heat release rate (HRR), peak heat release rate (pkHRR), mass loss rate (MLR), and effective heat of combustion (EHC) were reduced, respectively, by 30.8%, 30.7%, 42.0%, 16.7%, and 14.4%. The time to ignition (TTI) was doubled, so the fire spread could be effectively suppressed. Meanwhile, nano latex particles were attached to the interwoven fibers points and formed a "sea-island structure," which significantly improved the paper's mechanical properties, with bursting strength, tensile strength, stiffness, fracture work, and elongation increased by 18.60%, 5.72%, 10.64%, 17.00%, and 81.80%, respectively. It solved the problem that the inorganic flame-retardant particles often lead to the deterioration of the mechanical properties of paper. [ABSTRACT FROM AUTHOR]

Meta-aramid fibrid is prepared by precipitation, and aramid fibers are mixed with meta-aramid fibrid to make aramid paper by hot-pressing technology. Meta- -aramid fibrid possesses an excellent binding and adhesive properties with the aramid short fibers, yielding high mechanical properties of the aramid paper. The effects of hot-pressing temperature on the mechanical property of metaaramid paper are mainly discussed. Experimental results indicate that the mechanical property of aramid paper increases first and then decreases with the increase of hot-pressing temperature. The fundamental cause of this phenomenon is elucidated, and the aramid paper reaches its maximal mechanical property when the hot pressing temperature is 300 °C.. [ABSTRACT FROM AUTHOR]

In the present study, the comfort properties of knitted fabrics made from a two-ply yarn comprising a paper yarn and a cotton yarn were investigated. The objective was to elucidate the characteristics of paper yarn in comparison with cotton in terms of the design and development of comfortable and ecofriendly textiles that directly contact the skin. A two-ply yarn comprising a paper yarn made from abacá and a cotton yarn was prepared. Five fabrics with different proportions of paper were prepared by changing the knitting ratio of the two-ply yarn to a 100% cotton yarn. The mechanical properties (tensile, shearing, bending, compression, surface, contact area, and air permeability properties) and various thermal and moisture-transport properties of the fabric samples were determined. Those investigations revealed that the surface roughness increased, the friction coefficient decreased, the contact area decreased (in both the dry and wet state), the air permeability increased, the thermal conductivity increased, and the moisture diffusivity increased as the proportion of paper yarn increased. The fabric consisting of only the two-ply yarn was noticeably stiffer than the fabrics that also contained a pure cotton yarn. The results suggest the possibility of developing clothes that feel comfortable next to the skin, even when wet (e.g. underwear and socks) by knitting the two-ply yarn in a well-balanced ratio with cotton yarns. [ABSTRACT FROM AUTHOR]

Paper is an inherent hydrophilic material due to the hydroxyl groups contained in cellulose, which limits its applications in packaging materials. This study proposed a simple one-step method for preparing hydrophobic paper by introduction of chitin nanocrystals (ChNCs) and hexadecyltrimethoxysilane (HDTMS). The surface chemistry and morphology of coated paper were studied in detail. The 2%ChNCs/HDTMS coated paper was highly hydrophobic with a water contact angle greater than 130°, mainly due to the low surface energy provided by HDTMS. Compared with uncoated paper, the hydrophobic paper's tensile strength and water vapor barrier were significantly improved due to the addition of ChNCs. Meanwhile, the hydrophobic paper showed excellent environmental tolerance and mechanical stability. The survival rate of L929 cells on the modified paper was more than 80% by CCK-8 assay, which proved that the nanocoating was safe. In addition, the obtained hydrophobic coated paper can hold water, cola, green tea, milk, coffee, and orange juice for a long time and can be used as a straw to absorb liquid. This work prepared high-performance and green hydrophobic paper, which exhibits wide applications in food packaging. [Display omitted] • Hydrophobic paper coated with ChNCs/HDTMS was fabricated by one-step method. • ChNCs/HDTMS enhanced water vapor barrier and mechanical properties of paper. • The coated paper exhibited excellent environmental tolerance. • Hydrophobic paper showed antibacterial adhesion and satisfied biocompatibility. • The hydrophobic paper can be made into straw and paper cup. [ABSTRACT FROM AUTHOR]

Copyright of Experimental Technology & Management is the property of Experimental Technology & Management 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.)

Copyright of Journal of Materials Science & Engineering (1673-2812) is the property of Journal of Materials Science & Engineering 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.)