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With the implementation of the "plastic restriction order" and the demand for sustainable society development, biodegradable coatings derived from biomass materials have garnered significant interest. This study presents the synthesis of a double‐salt bio‐based waterborne polyurethane (PLA‐WPU) by utilizing poly(lactic acid) polyol (PLA) and isophorone diisocyanate (IPDI) as the main raw materials, along with 2,2‐dihydroxymethylpropionic acid (DMPA) and sodium ethylenediamine ethanesulfonate (A‐95) as a hydrophilic chain extender. Synergistic reinforcement of PLA‐WPU using hydrophobically modified cellulose nanocrystals (M‐CNC) and polycarbonate diimide (PDCDA). At an M‐CNC content of 3% relative to the effective mass of PLA‐WPU, the tensile strength reached 36.12 MPa. After 8 days a lipase PBS solution, the degradation rate reached 54%. Excellent waterproof performance was observed, exhibiting a contact angle of 143.5°. When applied as a surface coating on kraft paper, the Cobb 60 value decreased from 74.0 to 28.6 g/m2, while increasing the tensile strength by 451.3%. Importantly, the kraft paper maintained excellent waterproofing, mechanical strength, and high barrier properties even after repeated folding, high and low‐temperature conditions, and exposure to varying pH solutions. It proved to be both degradable and recyclable, making it a promising alternative to liner paper or plastic membrane, especially in food packaging. [ABSTRACT FROM AUTHOR]

Meta‐aramid paper is widely used in transformers because of its perfect heat resistance and dielectric properties. However, the loose structure and the voids of meta‐aramid paper may lead to lower breakdown strength, which will limit the applications of the insulated paper in harsh environment. Accordingly, it is urgent to enhance the dielectric breakdown strength of meta‐aramid paper. This work reports a simple and effective way to increase the breakdown strength of meta‐aramid paper. The paper was coated with salt‐free poly(m‐phenylene isophalamide) (PMIA) slurry and the solid contents of PMIA slurry were 4%, 6%, 8%, and 10%, respectively. To obtain salt‐free PMIA slurry, the meta‐aramid spun fibers were dissolved in dimethylacetamide. After coating 10% PMIA slurry on meta‐aramid paper, the paper demonstrated the best comprehensive performance. The tensile strengths in the cross and machine direction reached 40.67 and 90.76 MPa, which were increased by 29.93% and 20.16% compared with pristine paper. Meanwhile, the dielectric breakdown strength was up to 42.75 kV/mm (the breakdown strength of pristine paper was only 16.41 kV/mm). Because no crosslinking agent and adhesive were used, the coated meta‐aramid paper still maintained excellent properties. [ABSTRACT FROM AUTHOR]

It is crucial and significant to boost the utilization of renewable resources and exploitation of biodegradable materials alternative to petrochemical plastics. Waste paper, mainly composed of cellulose (82–95 wt%) and derived from the lignocellulose, is a type of abundant, renewable, and biodegradable resource, whose recycling use and conversion to high value‐added products can reduce the pressure on the environment and exert immense economic benefits. Herein, four kinds of common waste paper (e.g., printing paper, newspaper, straw paper and roll paper) were converted into cellulose‐based bioplastic membranes by using ionic liquid 1‐butyl‐3‐methyl‐imidazolium chloride as solvent. The cellulose‐based membranes are smooth and compact, and their mechanical strength is prominently improved about 3–100 times comparison with the original paper. The maximum tensile strength of the film (F4) is over 127 Mpa and its optical transmittance reaches 80% at 450–800 nm wavelength. Besides, this kind of cellulose‐based films have excellent biodegradability. Thus, the results demonstrated that the cellulose‐based bioplastic membranes stemmed from waste paper possess a magnificent application prospect. [ABSTRACT FROM AUTHOR]

As reported herein, a bilayer coating approach using poly(vinyl alcohol) (PVOH) and zein is employed to enhance the water vapor and oxygen barrier properties of paper materials. The coating was applied onto three different types of paper substrates to study the general applicability of this approach. The bilayer‐coated paper samples exhibited a reduction of up to 65% in their water vapor transmission rate in comparison to the corresponding uncoated paper substrates at 23°C and 50% relative humidity. In addition, the bilayer‐coated paper samples showed at least a 40‐fold decrease in oxygen transmission rate from that of the uncoated paper samples. In addition, the coated paper showed excellent thermal stability and mechanical properties. Scanning electron microscopy confirmed that the obtained coated paper has a smooth texture without pores. Pulp was recovered from the coated paper by washing with water/ethanol. Thus, this work provides a unique coated paper with excellent barrier properties and therefore has the potential for real‐world application as an alternative to single‐use plastics. [ABSTRACT FROM AUTHOR]

Paper‐based materials are widely used in various fields due to their advantages, such as environmental friendliness and sustainability. However, the highly hydrophilic nature of the cellulose that makes up paper‐based materials limits their use. In this paper, micron/nano‐graphite/polydimethylsiloxane (PDMS) coatings with excellent superhydrophobic and conductive properties were prepared on the surface of filter paper by a simple spraying method. A mixture of micro‐graphite and nano‐graphite was used to form a multistage rough structure on the surface of the filter paper by spraying, and the low surface energy PDMS enhanced the adhesion of the micro‐graphite and nano‐graphite on the surface of the filter paper. The results showed that the samples possessed the best superhydrophobic properties when the ratio of micro‐graphite to nano‐graphite was 1:1, at which time the contact and rolling angles of the samples were 165.4° and 3.2°, respectively. The prepared superhydrophobic samples have good bounce and self‐cleaning properties, while the samples have good mechanical stability and chemical resistance. Additionally, due to the conductivity of micro–nano‐graphite, both particle sizes closely contact the sample surface, creating a conductive network. With a 1:1 ratio of micro‐ and nano‐graphite, the coating exhibits minimal resistance at 1.89 KΩ, and the sample maintains stable conductivity even underwater. The above properties greatly extend the application range of paper‐based superhydrophobic materials. [ABSTRACT FROM AUTHOR]

Herein we report the development of bilayer‐coated‐paper with corn starch as the bottom layer and zein protein as the top layer. Two different methods were used for preparation of the coated paper, namely rod‐coating and dip‐coating techniques. The effect of the coating methods was studied by investigating the mechanical and barrier properties of the coated paper. A significant decrease of the water vapor and oxygen transmission rates at various temperatures and relative humidity conditions was observed. Considering the growing need for renewable and biodegradable alternatives to conventional plastics, the coated paper described herein may have strong potential for applications in the food packaging sector. [ABSTRACT FROM AUTHOR]

Based on the requirements of resource conservation and environmental development, an important factor for paper‐based materials to be able to completely replace plastic materials in the packaging field is their ability to achieve high‐barrier performance, especially thermal barrier performance under extreme working conditions. In this paper, we report the preparation of paper‐based high‐barrier materials utilizing silicone modified acrylate emulsions as coatings, followed by a comprehensive analysis of their application performance. The test results show that the Cobb value reaches 15.71 g/m2, the Kit grade reaches up to 10, and can slow down the penetration rate of castor oil at 80°C within 24 h. Based on our characterization results, we have constructed a microscopic model of paper‐based barrier material and analyzed the barrier mechanism of silicone emulsion coated paper from a molecular perspective. These findings offer valuable insights into the preparation of paper‐based barrier materials, providing process methods and application data. [ABSTRACT FROM AUTHOR]

A transparent, bendable, high oxygen barrier cellulose‐based film was prepared, which has far better oxygen barrier properties than conventional polyethylene, polypropylene and cellophane materials. A series of regenerated cellulose films (RCs) were prepared from filter paper lacking oxygen barrier properties under different cellulose concentrations and gelation times. It was shown that the cellulose concentration and gel time had a greater effect on the oxygen barrier properties of RCs. When the cellulose concentration was 4 wt% and the gel time was 3 h, the RCs obtained the lowest oxygen permeability coefficient (OPC) down to 2.21 × 10−17 cm3 cm cm−2 s−1 Pa−1. The films have a tensile strength of 109.5 MPa, an elongation at break of 27.3% and a light transmission rate of 89%. In further, molecular dynamics simulations showed that when the filter paper was converted to RCs, the increase in hydrogen bonding and the decrease in free volume between cellulose chains caused a decrease in the diffusion coefficient of oxygen. As a novel biobased high oxygen barrier material, the film has broad application prospect in packaging and chemical industry. [ABSTRACT FROM AUTHOR]

Air pollution caused by particulate matter (PM) poses an imminent threat to the global environment and public health. However, balancing the removal efficiency and pressure drop of most filter materials is difficult. Moreover, filter materials are non‐degradable and non‐recyclable, causing serious harm to the environment. Herein, a strategy to create fully degradable branched poly (lactic acid) (PLA) nanofibers based on electrospinning by adjusting the spinning solution properties was reported and branched PLA nanofibers were applied as nanofiber filter paper for air filtration materials. When the PLA and tetrabutylammonium chloride concentrations were 8 and 5 wt%, respectively, PLA nanofibers with branched structures were obtained. The obtained nanofibers possessed a small pore size (0.70 μm), high porosity (92.3%), appropriate mechanical properties, resulting in high PM0.3 removal efficiency (99.95%), low air resistance (79.67 Pa), and promising long‐term PM2.5 purification. Notably, branched T‐PLA‐5 nanofibers exhibited excellent filtration performance when applied to cellulose wood pulp paper. The filtration efficiency of the nanofiber filter paper remained stable above 85% for PM0.3 (32 L min−1) after 5000 backflushings. Thus, the preparation of such nanomaterials may provide new insights into the design and development of high‐performance degradable filtration materials for various applications. [ABSTRACT FROM AUTHOR]

A simple approach was developed to fabricate high‐performance MXene/cellulose (MC)‐based electromagnetic interference (EMI) shielding papers. The oriented MXene sheets located on one side of cellulose filter paper construct a continuous conductive layer, endowing the MC paper with high electrical conductivity (240.1 S/m) and excellent EMI shielding effectiveness (29.3 dB for 0.192‐mm thickness) at an MXene content of 0.72 vol%. Moreover, the EMI shielding effectiveness of four stacked MC papers reached 40.5 dB. This result means that 99.9911% of the microwave radiation is attenuated, and 0.0089% is transmitted, through the four‐piece MXene/cellulose filter papers. Therefore, MC paper has promising properties for excellent EMI shielding materials in current electronic devices. [ABSTRACT FROM AUTHOR]

The application of traditional cellulosic paper is limited because of its flammability, so it is necessary to explore new materials that can be used in the field of flame‐retardant paper. Based on the synergistic effect between fibers, flame‐retardant lyocell (FRL) and calcium alginate (FRL/Ca‐Alg) composite paper is prepared by a simple but efficient method. The thermal degradation process of the composite paper is analyzed by thermogravimetric (TG) and TG analysis coupled with Fourier transform infrared, the flame retardancy of the composite paper is analyzed by vertical flammability (VF) tests, limiting oxygen index test and cone calorimetry test, and the morphology of the residue after VF tests is observed by scanning electron microscopy. It is found that, the Ca‐Alg releases a large amount of CO2 before ignited, which delayed the ignited time of the composite paper; FRL reduces the effective combustion heat of composite paper during combustion, and the compact char formed by FRL effectively inhibits the smoldering of Ca‐Alg in the end stage of combustion. Based on these, the synergistic flame‐retardant effect of composite paper is proposed. [ABSTRACT FROM AUTHOR]

Reported herein is an economical, plastic‐ and fluorine‐free coating approach for oil and water repellent paper substrates using blends of poly(vinyl alcohol) and chitosan‐graft‐polydimethylsiloxane copolymer. The obtained coated paper showed good water‐resistance, as evidenced by its low Cobb60 values of ~20 ± 2.1 g/m2 and high water contact angles of 119 ± 6.3 °. The kit rating of the coated paper was 7.6/12, indicating decent grease‐resistant properties as compared to the kit value of 0/12 for the uncoated paper. The coated paper is also repulpable as demonstrated by the complete washing off the coating from the coated paper. Giving the cost‐effective nature of the coating materials and good water and oil‐resistant properties of the coated paper, the approach developed here is commercially viable, and will offer a multitude of environmental benefits such as the elimination of microplastic‐ and PFAS problems associated with existing paper coatings. [ABSTRACT FROM AUTHOR]

Renewable superhydrophobic materials have attracted great attention due to their extensive applications in the fields such as cost‐effective and biodegradable oil/water separation field. Herein, we reported an eco‐friendly and facile methodology to develop the superhydrophobic cellulosic paper by immersion method using the ethanol solution of stearic acid. Furthermore, the treated cellulosic papers showed super‐hydrophobicity with water contact angle (WCA) above 153°. Interestingly, this method can realize superhydrophobic‐hydrophilic conversion by simply adjusting the temperature and is amenable for different substrates and with the WCA of 114‐162°. More importantly, the utilization of fluorinated reagents has been avoided, thereby minimizing the production cost and improving safety and environmental aspects. Meanwhile, the modified natural cellulosic paper is applied for oil–water separation, and its separation efficiency was as high as 95% after 10 cycles, indicating the good reusability of stearic acid modified filter papers. Consequently, this simple strategy based on the stearic acid immersion method thus provided an easy conversion of superhydrophobic‐hydrophilic interface and provided facile strategies for conversion of commercial quantitative filter paper to functional materials for oil/water separation. [ABSTRACT FROM AUTHOR]

Flexible gas sensors made of polyaniline (PANI)‐reduced graphene oxide (rGO) nanocomposite were prepared using three different substrates, namely filter paper, cotton fabric, and weighing paper, through in‐situ reduction of GO and in‐situ polymerization of aniline. Preliminary analysis showed that the PANI/rGO coated on filter paper possesses a superior electrical conductance than PANI/rGO coated on cotton fabric and weighing paper. Such observation was attributed to the good attachment of the PANI/rGO nanocomposites onto the high‐density mesh‐like structure of the filter paper with rough surfaces. In contrast, PANI/rGO coated onto weighing paper and cotton fabric of different surface structures presented lower‐to‐almost negligible conductance. Accordingly, PANI/rGO filter paper was selected for the subsequent evaluation of gas sensing properties. The gas‐sensing performances of the PANI/rGO filter paper sensors indicated that the 5 wt% PANI/rGO (i.e., 5 wt% rGO) sample exhibited the best response of 306% for 500 ppm carbon dioxide (CO2) gas at room temperature with a recovery rate of 41.5%. On the other hand, the optimum recovery rate of 59.5% was identified at 0.5 wt% PANI/rGO sample which exhibited a response of 155%. Owing to the synergy effect, the PANI/rGO sensor outperformed the sensor made of pure PANI or pure rGO. [ABSTRACT FROM AUTHOR]

With the development of the "paper instead of plastic" trend, the investigation into high‐density, heavy‐weight paper has emerged as a point of interest in both academic and industrial realms. Regrettably, the paper‐strengthening agents that are commercially available fall short of meeting the strength specifications for such papers. To rectify this shortcoming, a water‐based acrylate paper‐strengthening agent (AA) was developed through radical emulsion polymerization. The most stable acrylate emulsion was obtained by amalgamating the anionic emulsifier allyloxyammonium oxymethyl sulfate nonylphenol ethoxy sulfate (DNS‐86) with the nonionic emulsifier nonylphenol polyoxyethylene ether (OP‐10) at a proportion of 1:0.6, with a dosage of 3%. Substituting the conventional strengthening agent (styrene‐butadiene latex) with the synthesized acrylate emulsion in wet‐end addition markedly improved the paper strength, registering a 54.8% increase to 29.4 MPa. The introduction of carboxylated cellulose nanofibers (C‐CNF) further bolstered the mechanical properties of the paper, achieving a tensile strength of 41.44 MPa and an elongation at a break of 3.55%. These results underscore the efficacy of acrylate as a paper‐strengthening agent and the crucial role of C‐CNF in enhancing the structural integrity of paper materials. [ABSTRACT FROM AUTHOR]

With the further development of the transmission and distribution network, the requirements for the insulating system of power equipment are further deepened. As one of the important factors, insulating paper is of great value to improve its performance. The pure cellulose model and trapezoidal polyphenylsesquisiloxane (T‐PPSQ) composite model are established to analyze the mechanical and thermal properties of insulating paper cellulose. The effects of T‐PPSQ doping at different temperature on properties of cellulose are investigated by comparing the radial distribution function, mechanical parameters, glass transition temperature, mean square displacement (MSD), and free volume fraction (FVF) through molecular dynamics method. The results show that T‐PPSQ can improve the ability of cellulose to resist shear stress at different temperatures, showing good mechanical properties. When the temperature is 423 K, the mechanical performance parameters elastic modulus, bulk modulus and shear modulus can be increased by 47.2%, 18.2%, and 38.56% at most. The glass transition temperature of the insulating paper cellulose with T‐PPSQ increases by 64 K, the MSD and the FVF all decrease at different temperature which demonstrated it has improved thermal stability. The research in this paper is of great significance for improving the life of the insulating system of power equipment. [ABSTRACT FROM AUTHOR]

ABSTRACT The production of traditional cellulose paper not only consumes lots of timber, but also brings about some environmental issues. Therefore, it is being increasingly replaced by synthetic paper. In this study, ultrahigh molecular weight polyethylene (UHMWPE)/SiO2 synthetic paper with high application performance was prepared by the thermally induced phase separation method using mineral oil as diluent. The corresponding properties of synthetic paper, including surface morphology, overall porosity, tensile strength, thermal stability, acid and alkali resistance, whiteness, and inkjet print effect were investigated respectively. The results show that the overall porosity of UHMWPE/SiO2 synthetic paper is above 45%, and the tensile strength exceeds 4.3 MPa. UHMWPE/SiO2 synthetic paper also presents light weight, as well as good resistance to heat, acid and alkali. Meanwhile, the average whiteness of the samples is up to 91.8%. The sample K-50, which contains 31.5 wt % SiO2, takes on the best print performance caused by its dense surface and higher SiO2 content. It is indicated that UHMWPE/SiO2 synthetic paper has good market prospects in the color printing. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 41529. [ABSTRACT FROM AUTHOR]

ABSTRACT: Conventional cellulosic paper, rendered electro‐conductive, may hold considerable promise for diversified applications in such areas as electro‐magnetic interference shielding and energy storage. Here, an electro‐conductive cellulosic paper was prepared by surface application of multi‐walled carbon nanotubes (MWCNTs)/polyaniline (PANI) nanocomposites onto a conventional base paper. MWCNTs/PANI nanocomposites were prepared by in situ polymerization of aniline with different contents of MWCNTs and used as electro‐conductive filler for the fabrication of electro‐conductive surface‐coated paper. The achieved MWCNTs/PANI nanocomposites exhibited a core‐shell structure, as evidenced by TEM. Effects of feeding ratios of MWCNTs on the rheological behavior of nanocomposite coatings, as well as the mechanical properties and electrical conductivity of surface‐coated paper were studied. Results revealed that the rheological behavior of the nanocomposite coatings showed strong dependence on the MWCNTs content. Moreover, both the electro‐conductivity and mechanical properties of surface‐coated paper were improved as a function of surface application of MWCNTs/PANI nanocomposites, particularly, in presence of an optimum content of MWCNTs. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46329. [ABSTRACT FROM AUTHOR]

Cross‐linked cationic polyvinyl alcohol (CPVA) is obtained by solution polymerization using vinyl acetate (VAc) and N‐(isobutoxymethyl)acrylamide (IBMA) as main raw materials and free radical co‐polymerization using glycidyl methacrylate (GMA) and dimethylaminoethyl methacrylate (DM) as modified monomers. The structure is characterized by HNMR. The effects of DM monomer on the properties of CPVA are investigated. It turns out that CPVA dispersion is a Bingham fluid with good stability. The particle size of CPVA reaches minimum and the value is 147.2 nm, which is in favor of infiltration into the paper. It is more suitable for the DM dosage ranging from 2% to 2.5% in light of the mechanical properties of CPVA film. The obtained CPVA is amorphous and the degree of crystallinity is decreased. When used as surface sizing agent for paper, the water absorption of the sizing paper reaches minimum and the folding resistance reaches maximum when DM is 2.5%. The maximum dry and wet tensile indexes of the paper are increased by 190.71% and 331.09%, respectively. SEM results shows that the larger pores between the paper fibers are filled and cross‐linked after CPVA sizing, which is beneficial to the improvement of paper strength. [ABSTRACT FROM AUTHOR]

The proliferation of microplastics in the ocean and other water bodies is becoming an alarming issue. The development of plastic‐free water‐ and oil‐resistant paper can contribute toward mitigating this problem. Herein we report a plastic‐free paper coating derived from chitosan and sunflower oil. Chitosan grafted sunflower oil paper coatings were prepared via the ring opening of the partially epoxidized sunflower oil with chitosan. The product of these reactions was characterized by nuclear magnetic resonance and infrared spectroscopy techniques. The sunflower oil grafted chitosan solution was coated onto a Kraft paper. The Cobb 60 and kit rating values were determined to be 8.00 g/m2 and 7.66, respectively, for the optimal formulations. Meanwhile, the water contact angle was found to be 94.0 ± 1.6° after 30 s. Scanning electron microscopy analysis was employed to gain insight regarding the changes that occurred on the paper surface at the microscopic level. [ABSTRACT FROM AUTHOR]

The development of green and efficient bio‐based flame retardants is very important for the development of flame‐retardant cellulosic paper. In this study, a novel type of starch‐based synergistic flame retardant (SAPU) was prepared using corn starch as carbon sources, amino trimethylphosphonic acid, and urea as phosphorus and nitrogen sources through the one‐pot method. Subsequently, the flame‐retardant cellulosic paper was prepared by impregnation, and the flame retardancy of the cellulosic paper was evaluated by vertical combustion, limiting oxygen index (LOI), and thermogravimetric analysis. The results demonstrated that the SAPU exhibited a favorable flame‐retardant effect on cellulosic paper. At a concentration of 25.0%, the vertical burning residue of flame‐retardant paper accounted for 49.16% of the total length of the paper sample, while the LOI was 39.4%. The tensile strength and burst index of cellulosic paper were found to be decreased by 6.36% and 19.1%, respectively, in comparison to the base paper. Conversely, the ring crush strength was observed to be increased by 156.2%. The carbon residue rate at 700°C under a nitrogen atmosphere rose from 11.56% of the base paper to 28.77% of the flame‐retardant paper. The flame‐retardant SAPU effectively improved the thermal stability of cellulosic paper. [ABSTRACT FROM AUTHOR]

In this work, poly‐ (methyl methacrylate) microparticles were effectively adsorbed onto the paper cellulose fiber surfaces during impregnation without crosslinking agents. The adsorption behavior and mechanism of microparticles onto paper cellulose fibers were further examined by physical and chemical property characterization in combination with adsorption kinetic model. We reported that the kinetic adsorption process included three phases: rapid adsorption, saturated adsorption, and equilibrium adsorption. Intermolecular hydrogen bonds which increased gradually with the increase of the mass concentration of PMMA microparticles occurred between the carboxyl group of PMMA microparticles and the hydroxyl group of paper cellulose fibers. Due to the increase of the interaction, the crystallinity‐index of the paper cellulose decreased. Furthermore, the hydrophobic interaction also occurred between PMMA microparticles and the paper fibers, leading to preferential adsorption of the microparticles on the surfaces of the hydrophobic (2 0 0) crystal cellulose. [ABSTRACT FROM AUTHOR]

Challenges in sustainable food packaging include ensuring effective moisture and oil barriers, antimicrobial protection, and developing cost‐effective, scalable production methods. This study introduces a hydrophobic, oil‐repelling, antimicrobial coating of a guar gum (GG)‐chitosan (CS) blend applied via a dip coating approach on blotting paper. By incorporating sodium tri‐polyphosphate (STPP) as a cross‐linker, the optimized formulation (1.5% guar gum, 0.09% STPP, 1% chitosan, and 1.5% glycerol) achieved notable hydrophobicity with a water contact angle of 136.1 ± 2.2°. This study is significant as it offers a sustainable, eco‐friendly food packaging solution with enhanced hydrophobic, oil‐repellent, and antimicrobial properties. [ABSTRACT FROM AUTHOR]

In this work, poly(para-phenylene terephthalamide) (PPTA)-pulp was investigated in view of employment in functional paper-based materials as reinforcement, bonding, and filling materials. The morphological characteristics, fibrillation degree and the role of PPTA-pulp, the ratio of PPTA-pulp to PPTA fiber on the mechanical properties, and paper formation uniformity of the functional base paper were discussed. The results showed that the ductile, rough, and highly fibrillating morphological characteristics of PPTA-pulp are helpful to give rise to some distinctive properties such as wet-machinability and reinforcement effects in composite materials. Fibrillation of PPTA-pulp significantly contributes to generating more highly dispersed slender threadlike micro-fibrils and improving the properties of base paper. This research suggested a significant reinforcement, bonding, and filling potential of PPTApulp for the production of functional paper composite materials. [ABSTRACT FROM AUTHOR]

The article discusses a study which investigated the adsorption of polystyrene latices that contain an alkali-hydrolysable cationic emulsifier. Study authors rinsed the polystyrene latices to desorbed the hydrolysis of the emulsifiers. They also showed ho some latices were adsorbed on the surface of the nonpretreated paper.

An ever‐increasing rise in demand for sustainable materials has received significant attention in developing biocomposites for structural applications. In this regard, natural fibers replacing synthetic fibers as reinforcement in epoxy composite could be a significant gain toward sustainability, especially in automobile and structural applications. Herein, flax fiber/cellulose paper–reinforced epoxy biocomposite (FREC‐X) was fabricated via a vacuum infusion process. The influence of postcuring conditions (time and temperature) and cellulose paper density on the mechanical properties of FREC‐X was studied. The tensile strength and modulus of FREC‐X increased by 37% and 64%, respectively, upon the integration of paper. Postcuring FREC‐X further augmented the tensile and flexural properties of the composite, which could be attributed to the increase in cross‐linking of the epoxy and yields a strong polymer network. Fractography analysis confirmed that the composites integrated with paper showed fewer defects with improved interfacial adhesion. In addition, the water absorption and thickness swelling results revealed that the presence of cellulose paper marginally increased the water uptake and thickness swelling of FREC‐X. Furthermore, there was no significant change in the tensile and flexural properties of FREC‐X observed even after immersing in water for >200 h. Such properties of FREC‐X seen as a fascinating alternative to synthetic fibers and petroleum‐based epoxy and are promising material for sustainable development. [ABSTRACT FROM AUTHOR]

Cellulose is commonly acknowledged as a sustainable material owing to its abundance and renewability. However, the abundance of hydroxyl groups makes the paper material highly hydrophilic, and the hydrogen bonds between the fibers are easily broken by water, leading to the degradation of mechanical properties. This work details the fabrication of a composite paper comprising interwoven cellulose and polylactic acid (PLA) structures through hot‐pressing and PLA impregnation onto handwritten paper derived from conventional wood pulp fibers as the substrate. The investigation assessed how varying PLA concentrations influenced the overall characteristics of the composite paper, including its morphology, structure, mechanical properties, water absorption behavior, and water contact angle. Experimental results revealed that the composite paper fabricated through our approach exhibited an intertwined structure comprising both PLA and cellulose. With a tensile index reaching 33.24 kN·m/kg and a mere 31.1% loss in tensile index post‐water treatment, the mechanical properties of the composite paper were significantly enhanced due to the robust interfacial compatibility between cellulose and PLA, as well as the adhesive effect of PLA. Furthermore, the composite paper (CP) is easily processable and amenable to thermoforming into paper trays as required, indicative of its potential applications in the packaging industry. [ABSTRACT FROM AUTHOR]

An anthocyanin (ACN) spectroscopic probe was extracted and immobilized into a matrix of cellulose nanocrystals (CNC)/urease enzyme to create a colorimetric nanocomposite film sensor. The ACN@CNC composite is a disposable molecular biosensor that uses urease as a catalyst, ACN as a molecular probe, and CNC as a probe carrier with a high surface area. The ACN spectroscopic probe was isolated from the pomegranate peel (Punica granatum L.). A mordant was applied to fix ACN onto CNC by forming nanoparticles (6–14 nm) of mordant/ACN (M/ACN) complexation. CNC showed diameters in the range of 11–21 nm, and crystal lengths of 55–130 nm. Under acid/base conditions, the ACN probe solution in distilled water exhibited a reversible color change, as shown by the UV–Vis absorption spectra. In order to create a biocomposite film, CNC were reinforced with a sodium alginate biopolymer. Upon exposure to urea in an aqueous solution, the ACN@CNC film biosensor changes color from purple (598 nm) to white (432 nm). The detection limit of urea was determined at 25–450 ppm. Various methods were utilized to investigate the morphological properties of CNC and ACN@CNC films. [ABSTRACT FROM AUTHOR]

Nanocrystalline cellulose (NCC) was prepared from office waste paper (OWP) by sulfuric acid hydrolysis method in this paper and it was used to prepare a series of poly (lactic acid) PLA/NCC composites by using a dissolution method in solvent N, N‐dimethylformamide solution. The results indicated that with the addition of only 3 wt% NCC, the composites exhibited outstanding mechanical property. The tensile, bending and impact properties of the PLA/3NCC composite were improved by 8.2%, 13.1%, and 35.9% than those of pure PLA, respectively. On this basis, office waste paper fibers (OWF) were also used as a physical blended filler to enhance PLA/NCC composites to reduce the preparation cost of PLA composites and the perfect PLA/NCC/OWF sample was easily manufactured by melting–blending and injection molding. According to the crystallization and melting performance table, both NCC and OWF can act as nucleating agent to promote the crystallization properties on composites, while the blends did not have positive effect on thermal stability. Furthermore, the water absorption and degradation properties of PLA composites were also studied. This work not only provided a novel idea for the utilization of office waste paper but also successfully produced environment friendly composites with favorable mechanical properties and crystallization performance. [ABSTRACT FROM AUTHOR]

Acid‐catalyzed hydrolysis of glycosidic bonds is the most important degradation mechanism affecting cellulose‐based materials. It results in the decrease of DP and in the loss of the original mechanical properties. The neutralization of acidity is therefore one of the most efficient ways to hamper the degradation of cellulosic artworks. However, in the case of acidic and strongly degraded artifacts, in addition to deacidification, a consolidation treatment must be performed. To this aim, a new class of biopolymers, obtained by a synthetic procedure that considers the principles of Sustainable Chemistry, was investigated. Three allyl saccharide/vinyl acetate copolymers, having different molar ratios between starting monomers, were prepared using α,α'‐trehalose, and used to synthesize the corresponding allyl saccharide/vinyl alcohol copolymers. The use of saccharide derivatives as monomers improves the affinity and compatibility of the biopolymer with the artifacts to be treated. After characterization, the efficacy of the copolymers in the strengthening of degraded paper was evaluated with mechanical tests. The most effective system was thus selected for further testing. Its performance was compared to that of Klucel G®, a commercial product belonging to the class of cellulose derivatives, which are largely used in conservation practice. [ABSTRACT FROM AUTHOR]

The chemical graft copolymerization reaction of acrylonitrile (AN) onto paper sheet was performed. The effect of initiator concentration, monomer concentration, and temperature on the reaction rate was studied. The reaction rate equation of the graft copolymerization reaction is found to be R = K [initiator][monomer]. The apparent activation energy ( E) of the copolymerization reaction is found to be 35.99 KJ/mol. The infrared characteristic absorption bands for cellulosic paper structure and the paper gr-AN are studied. Tensile break load, porosity, and burst strength were measured for the grafted and pure paper sheet. It was found that the mechanical properties are improved by grafting. The chemical resistance of the graft product against strong acid (HCl), strong alkali (NaOH), polar and nonpolar solvents was investigated. It was found that the resistance to these chemicals is enhanced by grafting. From the TGA and DTA data, it is clear that the grafted paper sheet is more thermally stable than pure paper sheet. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011 [ABSTRACT FROM AUTHOR]

ABSTRACT Composite materials made from fibrous support coated with agro-polymers are widely commercialized for different applications. But, their transfer properties have only been sparingly studied despite their importance in membrane technologies or food packaging. Furthermore, most of past studies on the topic have been focused on the impact of surface properties of the support on the final coated material structure and its properties; leaving unexplored the potential impact of the in-bulk structure of the support. This study demonstrated the influence of in-bulk structure and especially fibers refining degree of 4 kraft papers (SP28, 36, 60, and 80) on the structure, and surface and gas transfer properties of their respective wheat gluten (WG) coated papers (WGP28, 36, 60, and 80). Paper presenting a high fibers refining degree (SP28) exhibited very tight and narrow in bulk fibers network which prevented most of the WG-coated layer penetration, maintaining an important WG apparent layer on top of the paper and a small fibers/wheat gluten composite zone inside (WGP28). Such structure gave strong 'WG-like' properties to the final coated material with moderate oxygen permeation and high permselectivity (1.50 × 10−11 mol m−2 s−1 Pa−1 and 8.09, respectively for WGP28) whereas the highly impregnated structure of coated papers built on lowly refined papers (SP80, with wide and loose structure) gave coated materials presenting weak 'WG-like' properties, supposedly due to a thick composite zone presenting interfacial defects, with higher oxygen permeation and very limited permselectivity (11.90 × 10−11 mol m−2 s−1 Pa−1 and 1.06, respectively for WGP80). © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 2848-2858, 2013 [ABSTRACT FROM AUTHOR]

Environment friendly composites with favorable mechanical properties and low water absorption performance were successfully produced from poly(lactic acid) (PLA), office waste paper fiber (OWF), and coupling agents. The perfect sample was easily manufactured by melting–blending and injection molding. The PLA/OWF composites were comparable with other PLA/plant fiber composites, and the results indicated that the PLA/OWF composites show better performance than PLA/wheat straw fiber composites and PLA/bamboo fiber composites. On this basis, influence of modification of OWF on the properties of composites was investigated. The infrared results show that the OWF modification by different coupling agents was successful, and the scanning electron microscopy indicates that prepared composites exhibit good interfacial compatibility due to preferable binding force between fiber and matrix. With addition of 2 wt% γ‐(2,3‐propylene oxides)propyl trimethylsilane, the composite exhibits high tensile strength of 58.96 MPa, reflecting increase of 14% than the pure PLA. According to the crystallization and melting performance table, OWF can act as nucleating agent to promote the crystallization properties on composites, while the coupling agents have little effect on thermal stability. This article confirmed that the OWF has appropriate properties and is suitable for preparing composite materials and this work provides a novel idea for the utilization of office waste paper. [ABSTRACT FROM AUTHOR]

The chemical graft copolymerization reactions were used to enhance water resistance of paper by reaction of acrylonitrile (AN) monomer onto cellulosic paper sheet in the presence of comonomer (styrene or acrylic acid or itaconic acid) 1 : 1 molar ratio in dimethyl formamide using benzoyl peroxide as free radical initiator under nitrogen atmosphere at 70°C. The infrared spectroscopy confirms that graft copolymerization reaction occurs onto the paper samples. Water absorption test was carried out following the Normal Protocol 7/81 (water absorption by complete immersion) to evaluate the protective effect of the graft treatment onto the paper sheet. It was found that the three graft copolymerization systems reduced the water absorption of the investigated paper and the reduction of water absorption is directly proportional to the grafting %. The wettability of the grafted and ungrafted paper sheet samples were investigated using the wicking time method which exhibits the decreasing of paper sheet wettability using the AN/S comonomers in the graft copolymerization reaction. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013 [ABSTRACT FROM AUTHOR]

ABSTRACT Fluorescein silica nanoparticles (NPs) were prepared using a silane compound bound between fluorescein-N-hydroxysuccinimide (NHS-Fluorescein) and 3-aminopropylorthosilicate by a sol-gel method. The fluorescein-silica NPs were mixed with a poly(vinylidene fluoride) (PVDF) solution, and the solution loaded with the NPs was electrospun on a filter paper. Scanning electron microscopy and transmission electron microscopy images confirmed the encapsulation of the fluorescein silica NPs in the PVDF nanofibers. Laser scanning confocal microscopy (LSCM) images showed fluorescein silica NPs as dots, and photoluminescence (PL) images obtained using a fluoroanalyzer indicated the emission of uniform PL from filter papers coated with fluorescein-silica-NP-encapsulated PVDF nanofibers. It was demonstrated that the fluorescein silica NPs enabled PVDF nanofibers coated on a filter paper to be easily visualized. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 45125. [ABSTRACT FROM AUTHOR]

In this study, paper coated with a polyamide film containing a molecularly imprinted polymer (MIP) of benzalkonium chloride (BKC) is prepared. Its BKC adsorption ability and selectivity for BKC adsorption are investigated. The MIP is prepared by agitating an ethylenediamine solution containing an azo initiator, BKC as a template material, and methacrylic acid (MAA) as the functional monomer. First, filter paper soaked in this mixture is impregnated with a cyclohexane solution of terephthaloyl chloride and a BKC–MAA–MIP‐containing polyamide film is prepared on the surface of the paper. Paper containing BKC–MAA–MIP adsorbs BKC. The paper with the highest BKC removal efficiency is prepared under the following conditions: 4 mL MAA functional monomer, 2.5 w/v% ethylenediamine, and 10 min MIP synthesis time. The paper with BKC–MAA–MIP selectively adsorbs BKC from a solution containing BKC, tetracycline hydrochloride, and caffeine. Thus, a polyamide film containing BKC‐MAA‐MIP formed on paper can effectively and selectively remove BKC from aqueous environments. [ABSTRACT FROM AUTHOR]

This study investigates the effect of 1,2,3,4‐butane tetracarboxylic acid (BTCA) crosslinking treatment on the electrical properties of poly‐p‐phenylene terephthalate (PPTA)/cellulose insulation paper to prepare a novel composite insulation paper with low dielectric constant and good electrical performance. Three‐layer PPTA/cellulose composite paper crosslinked by BTCA under various conditions, composite paper without crosslinking, directly mixed composite paper, and conventional Kraft paper are prepared. The morphology and surface chemical composition of the paper samples are characterized. Dielectric, mechanical, and thermal properties are investigated. Results show that the BTCA concentration of 0.2 mol L−1 with a 180°C curing temperature is the relatively superior crosslinking condition to prepare a novel composite with low dielectric constant and good comprehensive performance. The dielectric constant and loss of the novel composite paper decrease to 3.21 and 0.392 at 50 Hz. The tensile strength of the BTCA crosslinked three‐layer PPTA/cellulose composite paper (thickness: 130 μm) has reached 10.01 kN m−1, increased by 41.6% than the directly mixed composite paper. The novel BTCA crosslinked composite paper also shows improved thermal stability. The BTCA crosslinking proves to be a promising method to improve the dielectric properties and electrical performance of the PPTA/cellulose composite paper. [ABSTRACT FROM AUTHOR]

In order to improve the flame‐retardant performance of insulating paper and reduce the fire risk, hydroxyethyl diphosphate and dicyandiamide were used to modify starch to prepare a new starch‐based flame retardant (SHPD). The combustion, mechanical, and electrical properties of SHPD treated flame‐retardant insulating paper were investigated. The results showed that when the impregnation concentration of SHPD was 25.0%, the limiting oxygen index of the insulating paper was increased from 18.3% to 38.3% and reached the level of UL‐94 V‐0. The tensile index and burst index of the flame‐retardant insulating papers were only 10.17% and 12.5% lower than that of the control insulating paper. The ring crush strength and alternating current breakdown strength in air of the flame‐retardant insulating papers were 63.3% and 1.8% higher than that of the control insulating paper. The SHPD flame retardant has a good application prospect in insulating paper. [ABSTRACT FROM AUTHOR]