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A significant increase in the consumption of recycled fiber products has been observed worldwide, and the industry is forced to solve the challenges of recycled fiber quality and add strength agents and/or virgin fibers to reach sufficient properties. In order to investigate whether the mechanical and air permeability properties of waste fiber (WF) material can be significantly improved by adding wood kraft fibers (KF), hemp soda fibers (HF), and ammonium persulfate oxidated cellulose nanofibrils (CNF), different fiber blends were prepared and tested. Results revealed the excellence of hemp fibers over wood fibers regarding the improvement of WF products. The results of WF after the addition of 10% mixed fibers (KF + HF) were higher than the results of a 50% KF addition. The impact of CNF depended on fiber composition and properties. A formula for modeling the CNF impact on different fiber compositions was proposed. Obtained fiber material samples showed suitability for home composting, thus contributing to the goals of the European Green Deal regarding reducing landfill waste and the development of cleaner products. [ABSTRACT FROM AUTHOR]

The demand for high-grammage paper, 150 g/m2 or more, is increasing for product protection and aesthetic value. Fold cracking, resulting from high mechanical pressure during folding, considerably decreases the economic feasibility of such products for papermaking companies. Fold cracking can be reduced through creasing, but defects possibly occur as fiber bonds are broken. In this study, the fold cracking of high-grammage paper that was not treated through creasing was explored. The mechanical and folding properties of six types of pulp fibers were evaluated based on their beating degree. The fines content of the fiber differed according to the beating condition. Using pulp with low fines content improved the folding properties. The mechanical properties of hardwood pulp were enhanced with increased beating degree. The mechanical properties of softwood pulp were considerably increased, and fold cracking occurred with increasing beating degree. Therefore, to improve the fold cracking, beating should be applied appropriately, following the type and mixing ratio of pulp fibers. Finally, softwood pulp mixing is proposed as a strategy to control fold cracking while maintaining the unique characteristics of high-grammage paper. [ABSTRACT FROM AUTHOR]

This study aims to comprehensively examine the influence of three distinct additives, namely carboxymethyl cellulose (CMC), hydroxypropyl methylcellulose (HPMC), and cellulose nanofibers (CNF), on the performance enhancement of corrugated base paper. For this purpose, steam‐exploded rice straw was treated with varying concentrations (2, 4, 6, 8, and 10 wt%) of CMC, HPMC and CNF. Analysis of the rice straw pre and post expansion, as well as the modified corrugated base paper, was conducted using Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), thermogravimetric analysis (TG), tensile performance testing, and scanning electron microscopy (SEM). Results indicated that adding CMC, CNF, and HPMC to corrugated base paper significantly improved bonding between paper layers, particularly at 2 %, 6 %, and 8 % concentrations, respectively. This enhancement notably increased tensile strength and elastic modulus of the corrugated base paper. Tensile performance saw increases of 57.76 %, 59.01 %, and 60.25 %, while elastic modulus showed increments of 52.7 %, 9.4 %, and 136.69 %, respectively. These findings provide valuable insights for the preparation of corrugated base paper and highlight the potential of CMC, HPMC, and CNF in enhancing paper mechanical properties. [ABSTRACT FROM AUTHOR]

The demand for particleboard has been increasing over the years. Currently, most particleboards are produced from wood which may not be sustainable in the long term. Therefore, there is need of exploring alternative materials such as making particleboards from waste materials. This study investigated the mechanical properties of particleboard consisting of waste leather shavings and waste papers blended together by unsaturated polyester. A single-layered particleboards were manufactured using compression method. Different resin contents (60%, 70%, 80%, and 90%) and leather/paper ratios (100:0, 25:75, 50:50, 75:25) were used to determine the effects on the mechanical properties (internal bond, bending strength, compression, and impact strength) of fabricated boards. From the results of this study, it was found that leather shavings and waste papers can be used as alternative raw materials for particleboard production and that mechanical properties were depended on the resin content and the blend ratio. Also, mechanical properties were reduced with resin content increment, except for impact strength, and improved by high paper blend ratio. It could be concluded that the produced particle panels could be used for indoor application or interior equipping. Additionally, it is recommended that further studies can be done on morphological analysis to establish the bonding between the particles and matrix.

The coefficient of friction for different contacting materials against skin is mainly influenced by the nature of the materials (synthetic and natural fabrics), mechanical contact parameters (interfacial pressure and sliding velocities), and physiological skin conditions (ambient humidity and skin moisture content). In the present research work, seven different types of papers used in everyday life were analyzed. The physical properties of these materials were determined through tensile tests and friction tests. By comparing mechanical properties with coefficient of friction, it was possible to conclude that the coefficient of friction is strongly correlated with the mechanical properties.

Meta‐aramid paper has been widely used in transformers because of its excellent insulation properties and thermal stability. However, with the rapid development of high‐voltage transformers, higher requirements are placed on the breakdown strength of meta‐aramid paper. In this study, meta‐aramid chopped fibers/polyphenylene sulfide (MACFs/PPS) composite paper was prepared by a combination of wet‐copying and hot‐rolling technology. Then the microscopic morphology, mechanical properties, crystallization behavior, insulation properties, and thermal stability of the MACFs/PPS composite paper were studied and evaluated. The experimental results showed that the breakdown strength of the MACFs/PPS composite paper was as high as 46.46 kV/mm, which was 2.7 times higher than the famous Nomex T410 insulating paper. Meanwhile, the MACFs/PPS composite paper presented good mechanical properties and thermal stability. This paper provides a simple and versatile method for the preparation of meta‐aramid composite paper with high breakdown strength. [ABSTRACT FROM AUTHOR]

A study was undertaken to make greaseproof packaging paper using banana pseudostem fiber. Kraft pulp produced from banana fiber was beaten to the freeness of 60°SR and 70°SR, and handsheets (40 ± 1 g/m2) produced were coated with carboxymethyl cellulose (3% and 5% w/v) and sodium alginate (3% and 5% w/v). Handsheets were compared based on differences in their mechanical (tensile index and bursting strength) and barrier properties (contact angle, grease resistance, and air resistance). Significant differences among the treatment were found for all the responses studied. Results obtained for ‘turpentine oil test’ showed that handsheets made at 70°SR and subsequently coated with 3% and 5% carboxymethyl cellulose had grease resistance properties. It was observed that handsheets (70°SR) coated with 5% carboxymethyl cellulose possess maximum tensile index (65.00 ± 3.46 Nm/g), burst strength (3.76 ± 0.21 kg/cm2), contact angle (41.27 ± 0.45º), and air resistance (29.95 ± 0.38 s/100 ml). However, if the amount of coating absorbed per unit area of the sheet is taken into consideration, handsheets produced with 70ºSR pulp freeness in combination with 3% carboxymethyl cellulose coating seem to be more efficient and can be used for packaging of butter.

This review focuses on polymeric waste-paper composites, including state-of-the-art analysis with quantitative and qualitative discussions. Waste paper is a valuable cellulose-rich material, produced mainly from office paper, newspaper, and paper sludge, which can be recycled and returned to paper production or used in a new life cycle. A systematic literature review found 75 publications on this material over the last 27 years, with half of those published during the last five years. These data represent an increasing trend in the number of publications and citations that have shown an interest in this field. Most of them investigated the physicomechanical properties of composites using different contents of raw waste paper or the treated, modified, and cellulose-extracted types. The results show that polyethylene and polypropylene are the most used matrices, but polylactic acid, a biodegradable/sourced polymer, has the most citations. The scientific relevance of waste-paper composites as a subject includes the increasing trend of the number of publications and citations over the years, as well as the gaps identified by keyword mapping and the qualitative discussion of the papers. Therefore, biopolymers and biobased polymers could be investigated more, as well as novel applications. The environmental impact in terms of stability and degradation should also receive more attention regarding sustainability and life cycle analyses. [ABSTRACT FROM AUTHOR]

The high production of paper, followed by a more significant concern with environmental and economic issues, has led to greater relevance to paper recycling and its raw uses as composite filler. Composites of polypropylene with 10, 20, and 30 wt.% of recycled office waste paper were produced by injection molding and characterized by mechanical and thermal properties. All composites presented a slight reduction of 15°C in thermal stability compared to the polymeric matrix. Moreover, as the filler amount increased, the degree of crystallinity was reduced proportionally. The mechanical test showed similar tensile strength values among neat polymer andcomposites but also showed an increase in the composite's tensile modulus, related to the stiffness of the natural filler. The composite with a higher percentage of waste paper (30 wt.%) maintained equivalent properties as neatpolypropylene and other composites (10 and 20 wt.%). Thus, 30 wt.% composites proved to be an excellent material with less synthetic polymer percentage, keeping thermal and mechanical properties comparable to the neat PP. Furthermore, this composite does not need chemical treatment or additives harmful to the environment. It is suitable for future applications in various plastic products such as packaging and domestic utensils. [ABSTRACT FROM AUTHOR]

In order to improve the hydrophobic and mechanical properties of paper mulch film, ZnO/SiO2 composite coated paper mulch film was prepared with a brush coating method. Hydrophobicity and durability of the original paper mulch film and the coated paper mulch film were measured by static contact angle and mechanical torsion tests, and the mechanical properties of the two kinds of paper mulch films were measured by tensile and tear tests at different temperatures. The two kinds of paper mulch films were characterized by their micro-morphology and surface element distribution. The results show that the contact angle of the ZnO/SiO2 composite coated paper mulch film reaches 161.46°, and the contact angle can still reach 153.15° after 80 mechanical torsion cycles, which shows good superhydrophobic and hydrophobic durability. Compared with the original paper mulch film, the mechanical properties of the coated paper mulch film are also improved to some extent. Combined with the surface micro-morphology, it is found that a ZnO/SiO2 composite coating fills the pores between fibers in the paper mulch film and promotes the adhesion between fibers, thus improving the hydrophobicity, durability, and mechanical properties of the paper mulch film. [ABSTRACT FROM AUTHOR]

Expansive soil exhibits significant swellings and shrinkages, which may result in severe damage or the collapse of structures built upon it. Calcium-based admixtures, such as lime, are commonly used to improve this problematic soil. However, traditional chemical additions can increase significant environmental stress. This paper proposes a sustainable solution, namely, the use of lignin fiber (LF) from the paper industry to partially replace lime as an amendment for expansive soils. Both the macroscopic and microscopic characteristics of the lignin fiber-treated expansive soil are extensively studied. The results show that the mechanical properties of expansive soil are improved by using lignin fiber alone. Under the condition of an optimal dosage of 8%, the compressive strength of lignin fiber-modified soil can reach 193 kPa, the shear strength is increased by 40% compared with the untreated soil, and the water conductivity is also improved with the increase in dosage. In addition, compared with 2% lime-modified soil, the compressive strength of 8% lignin fiber- and 2% lime composite-treated expansive soil increased by 50%, the cohesion increased by 12%, and the water conductivity decreased significantly. The microstructure analysis shows that at an 8% lignin fiber content, lignin fibers interweave into a network in the soil, which effectively enhances the strength and stability of the improved soil. Simultaneously, the fibers can form bridges across the adjacent micropores, leading to the merging of pores and transforming fine, dispersed micropores into larger, connected macropores. Lime promotes the flocculation of soil particles, forming larger aggregates and thus resulting in larger pores. The addition of fibers exerts an inhibitory effect on the flocculation reaction in the composite-improved soil. In conclusion, lignin fibers are an effective addition used to partially replace calcium admixture for the treatment of expansive soil, which provides a sustainable and environmentally friendly treatment scheme for reducing industrial waste. [ABSTRACT FROM AUTHOR]

The primary aim of this research was to explore the feasibility of producing environmentally friendly composite materials by employing diverse hybrid matrices consisting of dammar natural resin, supplemented with small proportions of two synthetic resins: one epoxy and the other acrylic. A blend of paper and chicken feathers served as the reinforcing elements. The fabrication of these composite materials utilized a hand layup technique. Targeted for applications in the furniture industry or interior design, their mechanical properties were assessed through various tests. Specimens were obtained from the manufactured samples and subjected to evaluations for tensile strength, compression, flexure, vibrations, Shore hardness, and water absorption. Results indicated that irrespective of the testing method employed, the mechanical strength properties exhibited a decline with an increase in the percentage of dammar in the hybrid resins, whereas the elasticity properties demonstrated an increase with this percentage. [ABSTRACT FROM AUTHOR]

To solve the environmental pollution and harm to human health caused by the use of adhesives in traditional paperboard, the development of environmentally friendly mycelium paperboard has become a hot topic. Due to the high dipole moment and hydrogen bonding between macromolecules, hyphae can form clamp shaped connection structures for nutrient reproduction and transfer, and can grow on natural agricultural waste, forming a natural biocomposite material. This study determined the combination of Ganoderma weberianum/corn straw, and designed single factor cultivation conditions such as cultivation time, straw particle size, and fructose addition to explore the effects on the mechanical properties, waterproof properties, and thermal decomposition performance of the hyphal paperboard formed by hot pressing. The optimal cultivation process was obtained through orthogonal experiments. The experimental results indicate that various factors have varying degrees of influence on the edgewise strength, flexural stiffness, and static bending strength and waterproofness of paperboard. Firstly, when the cultivation time was 30 days, the flexural stiffness reached 16.63 mN/m, which was 21.2% higher than the flexural stiffness of kraft paper (13.10 mN/m). Moreover, with the increase of cultivation time, the water absorption (24 hours) had also decreased from 3.92% to 1.27%. Secondly, previous research results have shown that the addition of fructose, glucose, and sucrose increases the biomass growth rate of strains. In this study, fructose was chosen as an exogenous nutrient, and the results showed that when a mass fraction of 5% fructose was added, the mechanical properties were the best, with a flexural stiffness of 18.87 mN/m, which was 30.5% higher than that of kraft paper (13.10 mN/m). Thirdly, the particle size of the sbstrate has a significant impact on the appearance and properties of the material. The results show that, from the appearance perspective, the mycelium paperboard made of 0.165～0.250 mm particle size has the closest appearance and feel to kraft paper. At the same time, during the testing period, it was found that the mycelium paperboard made of 0.165～0.250 mm straw was the least prone to deformation and loosening, and the molding effect was significantly improved compared to other components. In terms of mechanical properties, the edgewise strength increased by 17.4%, the static bending strength increased by 14.9%, and the flexural stiffness increased by 57.3%. The experimental results show that the degree of influence of various factors on the edgewise strength, flexural stiffness, and static bending strength of paperboard is in the order of particle size, cultivation time,fructose addition amount. When the particle size is 0.165～0.250 mm, the cultivation time is 30 days, and the fructose addition of 5.0%, the edgewise strength of the prepared paperboard is 14.36 N/mm, the static bending strength is 10.89 MPa, and the flexural stiffness is 33.09 mN/m. As the particle size decreases, the water absorption rate and water thickness expansion rate of the paperboard after 24 hours of water absorption decrease to 0.86% and 0.59%. The mycelium paperboard prepared by different single factors has the same thermal decomposition process, starting at around 150 ℃ and reaching its maximum at 350 ℃. This study provides a reference basis for the development and application of mycelium composite materials in the future. [ABSTRACT FROM AUTHOR]

Paper-based friction material is a typical paper-based composite that is usually cured via hot-pressing. This curing method does not account for the effect of pressure on the matrix resin, resulting in uneven distribution of resin in the material and reducing the mechanical properties of friction materials. To overcome the above shortcomings, a pre-curing method was introduced before hot-pressing, and the effects of different pre-curing degrees on the surface morphology and mechanical properties of paper-based friction materials were studied. The pre-curing degree significantly affected the resin distribution and interfacial bonding strength of the paper-based friction material. When the material was cured at 160 °C for 10 min, the pre-curing degree reached 60%. At this point, most of the resin was in a gel state, which could retain abundant pore structures on the material surface without causing mechanical damage to the fiber and resin matrix during hot-pressing. Ultimately, the paper-based friction material exhibited improved static mechanical properties, decreased permanent deformation, and reasonable dynamic mechanical properties.

Thermal aging and ultraviolet (UV) irradiation are used as methods to prepare samples of kraft paper spanning its full lifecycle within a high-voltage transformer, from new to end of life. The mechanical break strain is correlated with the degree of polymerization (DP), representing a progressive deterioration of mechanical properties during aging. Subsequent exposure to oil flow mimicking both normal plant operation and reclamation activities shows that aged paper exposed to high rates of flow experiences noticeable surface roughening. Despite this, no measurable erosion occurs even after long-term temperature/flow cycling in used mineral oil containing a notable particulate content. This indicates that kraft paper is unlikely to be eroded by normal reclamation activities, even in a severely aged asset. This confirms the validity of using this approach to extend plant life. [ABSTRACT FROM AUTHOR]

Expansive soil exhibits significant swellings and shrinkages, which may result in severe damage or the collapse of structures built upon it. Calcium-based admixtures, such as lime, are commonly used to improve this problematic soil. However, traditional chemical additions can increase significant environmental stress. This paper proposes a sustainable solution, namely, the use of lignin fiber (LF) from the paper industry to partially replace lime as an amendment for expansive soils. Both the macroscopic and microscopic characteristics of the lignin fiber-treated expansive soil are extensively studied. The results show that the mechanical properties of expansive soil are improved by using lignin fiber alone. Under the condition of an optimal dosage of 8%, the compressive strength of lignin fiber-modified soil can reach 193 kPa, the shear strength is increased by 40% compared with the untreated soil, and the water conductivity is also improved with the increase in dosage. In addition, compared with 2% lime-modified soil, the compressive strength of 8% lignin fiber- and 2% lime composite-treated expansive soil increased by 50%, the cohesion increased by 12%, and the water conductivity decreased significantly. The microstructure analysis shows that at an 8% lignin fiber content, lignin fibers interweave into a network in the soil, which effectively enhances the strength and stability of the improved soil. Simultaneously, the fibers can form bridges across the adjacent micropores, leading to the merging of pores and transforming fine, dispersed micropores into larger, connected macropores. Lime promotes the flocculation of soil particles, forming larger aggregates and thus resulting in larger pores. The addition of fibers exerts an inhibitory effect on the flocculation reaction in the composite-improved soil. In conclusion, lignin fibers are an effective addition used to partially replace calcium admixture for the treatment of expansive soil, which provides a sustainable and environmentally friendly treatment scheme for reducing industrial waste.

This study investigates the influence of fiber modification methods and beating degrees on the properties of paper sheets. Two different methods were used to modify fibers: NaOH + urea and TEMPO ((2,2,6,6-tetramethylpiperidin-1-yl)oxidanyl) and blended with traditional paper fibers. Subsequently, we evaluated the resulting sheets for their optical, strength, and thermo-mechanical characteristics. Notably, we also scrutinized sheets created exclusively with 100% TEMPO-modified fibers. The addition of modified fibers led to improvements in several strength properties, but it had a noteworthy negative impact on the optical properties of TEMPO-treated fibers compared to the other papers. Furthermore, thermal analysis revealed that the contraction rates of the samples increased considerably up to 40–50 °C for the out-of-plane direction and surpassed 130 °C for the in-plane direction. In general, the inclusion of modified fibers had a significant effect on thermo-mechanical properties. Specifically, TEMPO modification resulted in an increase in the maximum in-plane contraction ratio, shifting it from −0.40% to −0.59%, along with its corresponding temperature. This research underscores the potential of modified fibers to enhance paper properties and contribute to the development of more sustainable paper-based products. [ABSTRACT FROM AUTHOR]

This study measured the decrease in some mechanical properties of kraft paper used in packaging and bag production by examining the colour changes occurring in accordingly prepared standard samples subjected to UV influence. Thus, it is aimed to predict the mechanical properties of packages that have been exposed to sunlight over long periods of time with the colour change measurement, which is a non-destructive test, without the packaging deformation. Since there are mechanical differences between the cross-machine width and machine length of fabricated papers, these were measured separately. Measurements were made on papers exposed to UV for 0, 120, 240, 360, 480, 600, and 720 h. Tensile strength, strain at break, and tensile energy absorption (TEA) values were measured and also predicted for the kraft paper. For the prediction, the time and colour change values were used as independent variables, whereas the mechanical properties were taken as the dependent variables. The relationship between the time and colour change and the tensile strength, strain at break, and TEA variables in both the crossmachine and the machine directions were significant at the 5% level, and the R2 values were within acceptable limits. The results showed that the mechanical properties of the papers under UV effect decreased proportionally with the increase of the UV time. [ABSTRACT FROM AUTHOR]

The results of recent laboratory-scale studies regarding the joint effects of wet strengthening agent polyamide-amine-epichlorohydrin (PAE) and internal alkylketene dimer (AKD) sizing on Nordic bleached softwood pulp (NBSK) handsheets indicate that AKD internal sizing increases the wet strength of PAE wet strengthened handsheets. The boosting effect of the internal AKD sizing was long-lasting. At the molecular level the actual mechanism behind the effect is unclear. The present study examines if the enhanced effect of internal AKD sizing, which is potentially exploitable in practice, also occurs in paper made by VTT’s Suora pilot paper machine. The trials were done using a similar type of NBSK pulp and the same chemicals as in the laboratory-scale studies. The paper was formed at 400 m/min using a hybrid dewatering mode (Fourdrinier + gap). Just as in the laboratory-scale studies, the internal AKD sizing of PAE wet-strengthened NBSK paper resulted in a long-lasting increase of the paper wet strength. In accordance with the laboratory trials, internal AKD sizing had no noticeable effect on the dry tensile strength of the pilot-made paper. The only apparent difference to the earlier observations was an increase of dry tensile strength of the paper treated solely with PAE.

Recovered paper is the most important raw material for paper industry today and paper industry is one of the forerunners of circular economy. However, despite the long history with recycling the characterization of recovered paper quality is still not solved sufficiently. Here the automatic classification of paper objects can bring significant progress. Up to now, most technical approaches use NIR sensors and visual cameras, which can only “see” the surface of the objects. This often leads to misclassifications, since, for example, many packages look like graphic papers due to their printed surface. To improve these challenging classification tasks, sensors for mechanical properties of the paper objects can make an important contribution. In this paper, an automatic sensor is presented which can measure force characteristics when penetrating paper objects with specially shaped measuring tips. These force characteristics show good correlations to the mechanical properties determined in the laboratory according to standardized methods.

The paper industry is one of the sources of environment pollution. Therefore, the problem of efficient utilization of such wastes is an urgent one. One of the possible effective methods of paper industry waste recycling can be the application in epoxy composites. The review of literature proves a high scientific and industrial actuality of this thematic. Optical microscopy shows that 20 wt% of micro- and meso-particles of lignocellulose from waste-paper utilization leads to changes in morphology of composite due to interactions between phases. As a result, the key mechanic (modulus at bending, resistance to wear) and resistant (swelling, fire- resistance) parameters changed. At the same time, 20wt% filling do not importantly change compression and bending strength parameters. Filled composites (as fresh as aged) are noticeable more resistant in acetone-containing solvents. Effect of filling on resistance in H2O2 depends on its concentration and age of templates: aged 20%-filled composites are more resistant than unfilled - in 35% H2O2, but fresh 10%-filled composite destruct quickly (unlike unfilled)-in high-concentrated (60%) H2O2.

This review focuses on polymeric waste-paper composites, including state-of-the-art analysis with quantitative and qualitative discussions. Waste paper is a valuable cellulose-rich material, produced mainly from office paper, newspaper, and paper sludge, which can be recycled and returned to paper production or used in a new life cycle. A systematic literature review found 75 publications on this material over the last 27 years, with half of those published during the last five years. These data represent an increasing trend in the number of publications and citations that have shown an interest in this field. Most of them investigated the physicomechanical properties of composites using different contents of raw waste paper or the treated, modified, and cellulose-extracted types. The results show that polyethylene and polypropylene are the most used matrices, but polylactic acid, a biodegradable/sourced polymer, has the most citations. The scientific relevance of waste-paper composites as a subject includes the increasing trend of the number of publications and citations over the years, as well as the gaps identified by keyword mapping and the qualitative discussion of the papers. Therefore, biopolymers and biobased polymers could be investigated more, as well as novel applications. The environmental impact in terms of stability and degradation should also receive more attention regarding sustainability and life cycle analyses.

Copyright of China Pulp & Paper is the property of China Pulp & Paper Magazines Publisher 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.)

Poly (p-phenylene benzoisoxazole ; PBO) paper is a potential raw material for use in honeycomb sandwich composites in the aerospace industry, which are able to sustain high temperatures exceeding 300°C. This work presents a wet-forming method of making PBO paper, consisting of PBO chopped fibers. The paper was impregnated with phenolic resin to simulate honeycomb wall material. The structure and mechanical and dynamic mechanical properties of the raw and impregnated paper were characterized. The performance of PBO paper was tested against p -aramid paper. The comparative results showed the tensile strength of PBO raw paper was 2.17 kN/m, which was slightly worse than p -aramid raw paper: 2.66 kN/m. After impregnation, the tensile strength of the PBO paper was 13.93 kN/m due to the increase in the number of bonding points—better than p -aramid paper: 7.99 kN/m. The tearing resistance value for PBO raw paper versus p -aramid raw paper was 3252 mN against 845 mN. The morphology of the torn samples in the impregnated paper revealed higher levels of PBO fiber pullout than p -aramid fiber, therefore the tearing resistance value was 6000 mN for PBO impregnated paper, which was again superior to p -aramid impregnated paper: 675 mN. The PBO paper also showed higher storage modulus than p -aramid paper after impregnation. Experimental studies showed that PBO paper could be used in load-bearing structures and in honeycomb components where high resistance to deformation and thermal stability is necessary. [ABSTRACT FROM AUTHOR]

Embossing is a functional and strategic process for creating high-quality multi-sensory tissue-paper products. Embossing modifies the sheet surface by generating hill and/or valley designs, changing the third-dimension z with a compressive die. This research work specifically concerns the impact study of the engraving finishing geometry on the final properties of tissue paper. This work led us to conclude that, even though the sheets individually present a higher hand-feel (HF) value for the straight finishing geometry, the highest softness was obtained in the two-ply prototype for the round finishing geometry. Moreover, this study confirmed that the HF value reduces with the increase of the bulk, being more accentuated for the micropattern. Relevant differences could not be seen in the spreading kinetics of the liquid droplets over time. Thus, the finishing geometry of the 3D plates did not impact the absorption kinetics on these samples. The finite element model allows us to understand the effect of the plate pattern and its finishing geometry on the paper, and the simulation results were in accordance with the experimental results, showing the same trend where patterns with a round finishing geometry marked the tissue-paper sheet more than patterns with a straight finishing did.

Simultaneous effects of using cellulose nanocellulose and chemical pulp in paper money were studied with bottom combers cotton pulp. The bottom combers pulp and chemical pulp were prepared in a factory that produced durable paper, and their products were transferred to the laboratory. The nanocellulose was prepared by Nano Novin Polymer Co. and was consumed at 4 levels, i.e., 0%, 0.3%, 0.6%, and 0.9%. After commixing the pulp with the nanocellulose at the identified percentages, handsheets of 90 g∙m-2 papers were produced. The results showed that by increasing the amount of nanocellulose, up to 0.9%, the tensile strength index, burst strength index, tear strength index, and folding endurance increased 22.7%, 38.9%, 7.7%, and 348%, respectively, when compared with the control sample. Enhancement via nanocellulose up to 0.9% increased the surface smoothness up to 7.9% compared with the control sample, while the air resistance and Cobb decreased 69% and 7.9% in comparison with control sample, respectively. By increasing the nanocellulose content up to 0.9% the opacity increased 0.7%; moreover, the brightness and whitening decreased 3.5% and 10.6, respectively. The scanning electron microscopy results indicated that enhancement via nanocellulose decreased the air resistance. [ABSTRACT FROM AUTHOR]

Fluorescence is well-known nowadays as one of the most efficient anti-counterfeiting techniques. Zinc oxide quantum dots (ZnOQds) are exceptionally fluorescence when exposed to ultraviolet (UV) light, which makes them a candidate for anti-counterfeiting printing. The resulting anti-counterfeiting papers are sustainable and resistance against organic dyes. In this work, ZnOQds were prepared via a green method and characterized under UV–visible spectroscopy, along with microscopic observations by transmission electron microscopy (TEM) and crystallography by X-ray diffraction (XRD). Formation of ZnOQds nanocrystals with an average partials size of 7.3 nm was approved. Additionally, double-layers sheets were prepared at two loading concentrations of ZnOQds, namely 0.5 and 1 (wt./v) and underwent characterization using a topographical surface study via field emission scanning electron microscopy (FE-SEM). Hybrid sheets were mechanically more stable compared to single-layer paper and likewise polymer film. Moreover, aging simulation approved a high stability for hybrid sheets. Particularly, the photoluminescence emission affirmed anti-aging character of hybrid paper for more than 25 years. The hybrid sheets also showed a broad range of antimicrobial activity.

Aramid chopped fibers/polyphenylene sulfide (ACFs/PPS) composite paper exhibits great potential for application in several cutting‐edge areas because of their excellent comprehensive properties. However, the mechanism underlying thermal aging and the role it plays in the performance of ACF/PPS composite paper remain poorly characterized. Herein, we studied the change in the chemical structure of ACFs/PPS composite paper during thermal oxidative aging and investigated the correlation between the evolution of chromophore/auxochrome groups and the development of color appearance in the ACFs/PPS composite paper. Using the color space theory, we established a correlation model among the degrees of thermal aging, the evolution of color appearance, and the changes in the mechanical properties of ACFs/PPS composite paper. On the basis of this model, the degree of aging and the corresponding mechanical strength of ACFs/PPS composite paper under different conditions could be rapidly received by estimating the change in color factor only. This study sheds new light on elucidates and provides a method for the study of polymer thermal oxidative aging. [ABSTRACT FROM AUTHOR]

Typical scanning electron microscopy (SEM) micrographs obtained for cellulose nanofibrils (a), paper handsheets surface without CNF addition (b) and with 10% CNF (c) Cellulose nanofibrils used as reinforcement go through the fibrillation process in equipment that have discs with grooves on the surfaces against which the pulp is exposed to cyclical and sequential stresses. Preparation of paper handsheets (fiber/CNF) CNF were added directly to the cellulose pulp at 0, 2, 5, 8 and 10 wt% proportion before forming the paper handsheets. Box-plot for tensile index (a), tearing index (b), bursting index (c), stretch (d) and modulus of elasticity (e) in paper handsheets with the addition of different amounts of nanofibrils Figure 6 shows the variations of tensile (a), tearing (b), and bursting (c) indexes, and stretch (d) and modulus of elasticity (e) of cellulose paper handsheets due the addition of different CNF contents. Keywords: Composite fibers; kraft paper; mechanical properties; cellulose microfibrils (CMF); nanocellulose; papermaking; ; ; ; (CMF); ; EN Composite fibers kraft paper mechanical properties cellulose microfibrils (CMF) nanocellulose papermaking ZH (CMF) 7818 7833 16 11/21/22 20221220 NES 221220 GRAPHICAL ABSTRACT Graph Introduction Cellulose nanofibrils (CNF) or cellulose microfibrils (CMF) are known to present unique properties such as high strength and stiffness and to enable numerous applications such as reinforcement material in composites and paper (Osong, Norgren, and Engstrand [21]). [Extracted from the article]

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The overall usefulness of the bursting energy absorption (BEA) was studied for a better analysis of paper strength properties. Additionally, the changes of the BEA during more complex deformations of paper products, e.g., preliminary or simultaneous tensile and burst, were determined. For the purpose of the research, an experimental setup was designed. The results showed that the correlation between BEA and bursting strength was linear, but the proportionality strongly depended on paper grade. Thus, a more accurate method to characterize the bursting resistance (BR) of paper was proposed. The BR parameter is described by the three following parameters: average bursting strength, average bursting energy absorption, and the slope of the fitted linear regression curve (relationship between the bursting energy absorption and the bursting strength). This method revealed new mechanical behaviors of papers related to their preloading. [ABSTRACT FROM AUTHOR]

Bagasse sugarcane (BSC) has low fibre strength due to low cellulose content. Hence, by adding a strong secondary fibre that is high in cellulose such as pineapple leaf fibre (PALF), the fibre strength of the system can be improved. High portion of PALF decreased the composite paper performance because the high composition of PALF tends to produce flocs and agglomerates fibres. The arrangement of the fibres in composite paper should be improved so that this agglomerate's effect could be overcome. A novel multilayer hybrid fibre composite was used. BSC/PALF with several hybrid ratios was studied in terms of the mechanical and moisture properties of the produced paper sheet and the results showed that multilayer hybrid composite paper produced higher in hybrid composite paper's properties compared with random hybrid composite paper. The colour of multilayer hybrid fibre composite paper resembled the natural bright colour of BSC and the multilayer hybrid fibre composite paper also shown a slightly low weight loss percentage compared with the random hybrid fibre composite paper after 60 days of soil burial test. As a conclusion, multilayer hybrid fibre composite produced the stronger interfibre bonding and overcome the agglomerate's effect between BSC/PALF compared with random hybrid fibre composite. [ABSTRACT FROM AUTHOR]