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Microbial degradation of lignin, a natural complex biopolymer, a renewable raw material with a wide range of applications, has been mainly directed at fungal systems, nevertheless, recent studies have proposed the bacterial role in lignin degradation and modification since bacteria possess remarkable environmental adaptability, and various production of enzymes and biochemistry. An occurrence of a high proportion of lignin-degrading genes has been confirmed in actinobacteria and proteobacteria classes by bioinformatics analysis, which points to the probability of undiscovered pathways and enzymes. Because of that, bacterial lignin decomposition might be substantially different from fungal lignin decomposition. Bacteria capable of lignin modification and degradation belong to actinomycetes, some Firmicutes, α-proteobacteria, and γ-proteobacteria. The enzymes responsible for lignin degradation are lignin peroxidase, manganese-dependent peroxidase, versatile peroxidase, dye-decolourizing peroxidase, and laccases. One of the main lignin producers is the pulp and paper manufacturing industry. Lignolytic microorganisms have been identified from diverse habitats, such as in plants, soil, wood, and the gut. Bacterial strains Bacillus, Rhodococcus, Sterptomyces, and Pseudomonas have been reported to have lignin decomposition ability. This review aims to describe the role of bacteria in lignin degradation, bacterial species, and bacterial enzymes included in lignin degradation. Several reports about bacterial species involved in lignin degradation are also highlighted, and the current state of the knowledge on the degradation of lignin from the pulp and paper manufacturing industry are reported. [ABSTRACT FROM AUTHOR]

There is current interest in using agro-based biopolymers in industrial applications. Because cottonseed protein is abundantly available, it would be useful to explore its feasibility as a polymeric additive and possible substitute for petroleum-based materials. In this work, we studied cottonseed protein isolate as a paper additive and observed its effects on the paper’s dry and wet strength. The tensile strength of paper was found to vary with the amount of the protein applied. By application of an 11% protein solution to the paper, the dry and wet strength increased by 33 and 16% compared with the paper by itself, respectively. The combined use of cottonseed protein and an acid (acetic, adipic, aspartic, and citric acids) to promote adhesion resulted in even greater dry paper strength but not in greater wet paper strength. Thermogravimetric analysis, infrared spectroscopy, and scanning electron microscopic studies suggested that the protein interacted with acid and that both components interacted with paper fibers to produce increased strength. [ABSTRACT FROM AUTHOR]

Coatings contribute to about 10% of the overall cost of paper production of which, the binder is the highest cost component in the formulation. In addition to costs, the binders that are currently being used are synthesized from fossil fuel feedstock raising concerns towards the sustainability of paper coatings. Furthermore, papers coated with waxes, polyolefins and other synthetic materials are difficult to recycle or compost. These challenges inherent with synthetic binders can be addressed by using renewable, plant based binders. This research focused on an abundant and underutilized source of hemicellulose based binders (DG gum) that can be extracted from distiller's dried grains. The extracted binder was compared with polyvinyl alcohol (PVA) in a coating formulation consisting of 10:1 CaCO 3 to binder formulation coated on light weight paper. Cobb test, dry and wet tensile tests, optical properties (brightness, color, opacity), water vapor transmission rate (WVTR) analysis were performed to compare the hemicellulose based binder with PVA. The results indicate water absorptivity reduction by 25% for both DG gum and PVA coatings from the base paper value. Dry tensile index was lower with higher coating weights for both coatings with similar performance. The performance on WVTR analysis for both coatings was also comparable. No significant differences in optical properties after coating were observed from that of the base paper. These results suggest that hemicellulose based binder extracted from distiller's grains has the potential to replace synthetic binders in paper coating formulations. [ABSTRACT FROM AUTHOR]

In continuation of previously reported results, the ionic liquid 1,5-diazabicyclo[4.3.0]non-5-ene-1-ium acetate was also found to be a powerful non-derivatizing solvent for cellulosic waste such as paper and cardboard. The ionic liquid could dissolve all the present bio-polymers (cellulose, hemicellulose, and lignin) in high concentrations, resulting in solutions with visco-elastic properties that were suitable for dry-jet wet fiber spinning. The cellulosic raw materials were refined gradually to identify the influence of residual components on the spinnability of the respective solution. Polymer degradation and losses in the spinning process could be avoided nearly entirely. With the exception of virtually unrefined cardboard, all the samples showed excellent spinnability, resulting in fibers with high tensile strength. Prototype textiles were produced to validate the quality of the fibers and demonstrate the possibility of using residual lignin in cardboard as a natural dye. [ABSTRACT FROM AUTHOR]

Nonwoven membranes based on electrospun fibers are of great interest in applications such as biomedical, filtering, and protective clothing. The poor mechanical performance is a limitation, as is some of the electrospinning solvents. To address these problems, porous nonwoven membranes based on nanofibrillated cellulose (NFC) modified by a hydroxyethyl cellulose (HEC) polymer coating are prepared. NFC/HEC aqueous suspensions are subjected to simple vacuum filtration in a paper-making fashion, followed by supercritical CO(2) drying. These nonwoven nanocomposite membranes are truly nanostructured and exhibit a nanoporous network structure with high specific surface area, as analyzed by nitrogen adsorption and FE-SEM. Mechanical properties evaluated by tensile tests show high strength combined with remarkably high strain to failure of up to 55%. XRD analysis revealed significant fibril realignment during tensile stretching. After postdrawing of the random mats, the modulus and strength are strongly increased. The present preparation route uses components from renewable resources, is environmentally friendly, and results in permeable membranes of exceptional mechanical performance.

Assuming dipole-dipole interaction as the dominant relaxation mechanism of protons of water molecules adsorbed onto macromolecule (biopolymer) surfaces we have been able to model the dependences of relaxation rates on temperature and frequency. For adsorbed water molecules the correlation times are of the order of 10(-5)s, for which the dispersion region of spin-lattice relaxation rates in the rotating frame R(1)(ρ)=1/T(1)(ρ) appears over a range of easily accessible B(1) values. Measurements of T(1)(ρ) at constant temperature and different B(1) values then give the "dispersion profiles" for biopolymers. Fitting a theoretical relaxation model to these profiles allows for the estimation of correlation times. This way of obtaining the correlation time is easier and faster than approaches involving measurements of the temperature dependence of R(1)=1/T(1). The T(1)(ρ) dispersion approach, as a tool for molecular dynamics study, has been demonstrated for several hydrated biopolymer systems including crystalline cellulose, starch of different origins (potato, corn, oat, wheat), paper (modern, old) and lyophilized proteins (albumin, lysozyme)., (Copyright © 2010 Elsevier Inc. All rights reserved.)

The barrier resistance and wettability of papers are commonly controlled by the application of petroleum-based derivatives such as polyethylene, waxes and/or fluor-derivatives as coating. While surface hydrophobicity is improved by employing these polymers, they have become disfavored due to limitations in fossil-oil resources, poor recyclability, and environmental concerns on generated waste with lack of biodegradation. Alternatively, biopolymers including polysaccharides, proteins, lipids and polyesters can be used to formulate new pathways for fully bio-based paper coatings. However, difficulties in processing of most biopolymers may arise due to hydrophilicity, crystallization behavior, brittleness or melt instabilities that hinder a full exploitation at industrial scale. Therefore, blending with other biopolymers, plasticizers and compatibilizers is advantageous to improve the coating performance. In this paper, an overview of barrier properties and processing of bio-based polymers and their composites as paper coating will be discussed. In particular, recent technical advances in nanotechnological routes for bio-based nano- composite coatings will be summarized, including the use of biopolymer nanoparticles, or nanofillers such as nanoclay and nanocellulose. The combination of biopolymers along with surface modification of nanofillers can be used to create hierarchical structures that enhance hydrophobicity, complete barrier protection and functionalities of coated papers. [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]

Herein we are reporting, the in-situ synthesis of polydopamine capped silver nanoparticles (PDA-AgNPs) and its cysteamine (CYS) and tetracycline (TC) drugs sensor applications. The synthesized PDA-AgNPs was characterized by UV–Visible, Fourier Transformed–Infrared, X-Ray Diffraction, Zeta Potential, and High Resolution-Transmission Electron Microscope techniques. We have utilized PDA-AgNPs as probes for the detection of CYS and TC by spectrophotometry method. The addition of CYS has led to a decrease in the absorption of PDA-AgNPs. The yellow color solution becomes colorless and observed the aggregated particles in the TEM image. In contrast, the addition of TC, into the same solution, absorption of PDA-AgNPs was increased. The color of the solution became dark yellow and the particles are obtained de-aggregation. Based on the Surface Plasmon Resonance (SPR) band absorption changes, the detection limit of CYS and TC was calculated to be 180 nM and 17 nM, respectively. Interestingly, 600-fold of common interferences did not interfere with the detection of CYS and TC. PDA-AgNPs was successfully utilized to detect CYS and TC in serum, urine, and drug samples. Finally, we have prepared a paper-based colorimetric kit for on-site monitoring of CYS and TC. [ABSTRACT FROM AUTHOR]

Over the last few years, the microfluidics phenomenon coupled with the Internet of Things (IoT) using innovative nano-functional materials has been recognized as a sustainable and economical tool for point-of-care testing (POCT) of various pathogens influencing human health. The sensors based on these phenomena aim to be designed for cost-effectiveness, make it handy, environment-friendly, and get an accurate, easy, and rapid response. Considering the burgeoning importance of analytical devices in the healthcare domain, this review paper is based on the gist of sensing aspects of the microfabricated paper-based analytical devices (μPADs). The article discusses the various used design methodologies and fabrication approaches and elucidates the recently reported surface modification strategies, detection mechanisms viz., colorimetric, electrochemical, fluorescence, electrochemiluminescence, etc. In a nutshell, this article summarizes the state-of-the-art research work carried out over the nano functionalized paper-based analytical devices and associated challenges/solutions in the point of care testing domain. [ABSTRACT FROM AUTHOR]

High-pressure size-exclusion liquid chromatography and infrared microscopy were coupled to investigate the molecular weight and nature of extracellular polymeric substances (EPS) from various activated sludges. Six main families of compounds (proteins, polysaccharides, organic acids, lipids, mineral phases) were found either as a single molecule or as associations. The molecular weight of proteins varied from small (10 kDa) to large (600 kDa) sizes, while all polysaccharides were smaller than 1 kDa. Association of different molecules implied the presence of species large in size. The EPS chromatographic fingerprints of sludge from various origins remained stable in normal operating conditions, but were drastically modified during settling crises. In poor settling conditions, the EPS with smaller molecular sizes always prevailed and large polymers were underrepresented. The EPS identified in activated sludge were collected in a chemical database which provides the basis for comparison of municipal and industrial wastewater treatment plants (WWTP).

Abstract: Bacterial cellulose was combined with wood cellulose papers in order to obtain biomaterials with increased barrier properties. For this purpose, different parameters were assessed: two producing bacterial strains (Komagataeibacter xylinus and Gluconacetobacter sucrofermentans), two paper supports to hold bacterial cellulose (filter paper and eucalyptus paper), two kinds of combined biomaterials (composite and bilayer) and two drying temperatures (90 °C and room temperature). Papers with increased barrier properties (100° of water contact angle, 1220 s of water drop test and air permeability < 1 µm (Pa s)−1) were obtained by the addition of bacterial cellulose to each paper support. However, due to the lower initial barrier properties of filter paper, higher improvements were produced with this paper. In addition, bacterial cellulose provided smoother surfaces with higher gloss without a detrimental effect on physical properties. Higher resistance to water absorption was obtained with K. xylinus possibly explained by its longer size fibers than G. sucrofermentans, as analysed by SEM. Smoothness and gloss were specially increased in the bilayer biomaterial although resistance to air and water were further improved in the composite. In this biomaterial drying at high temperature had a detrimental effect. SEM analysis of the products obtained showed the intimate contact among fibers of bacterial cellulose and wood paper. Results obtained show the contribution of bacterial cellulose to improve the properties of paper and its potential for the design of new added value paper products from biomass.Graphical abstract: [ABSTRACT FROM AUTHOR]

Perfluorinated compounds (PFCs) is a family of carcinogen that possess unique properties of highly chemically stable, high surface activity and higher thermal resistance that have been extensively used in the manufacturing industry as for the production of consumer products such as textile, film-forming foam, fluoropolymers, and many other industrial processes. Recently, emerging contamination of PFCs is increasing concerns among the environmental quality experts globally due to their toxicity, detrimental effect, persistent and hard to biodegrade in the environment. The mixture of the aqueous solution containing hazardous PFCs has led to serious water contamination into our main water sources and potentially brings tremendously adverse effects, risk of diseases and disorders towards an abiotic and biotic ecosystem that was specifically threatening the living organisms' health such as plant, animal and human. The elimination of PFCs pollutants is essential and has been crucial to demand attention to conserve pure, clean, and safe water resources. Herein, the feasibility of remediating PFCs from polluted aqueous solution by using various types of functional hybrid adsorbents based on natural polymers through a superior adsorptive mechanism has been reported in detail in this review paper. Particularly, the use of natural and renewable polymeric material on the fabrication of natural polymer-based adsorbents has been owing to their peculiar characteristics such as biodegradability, economic viability, the potential to reuse, and comprised of abundantly functional groups that can encourage and empower the elimination process of PFCs. The adsorption behaviour on several classes of PFCs onto different types of hybrid adsorbents was summarized, and various possible interactions mechanism like electrostatic attraction, ion exchange, hydrophobic interaction, and hydrogen bonding were fully reviewed. Moreover, the adsorption performance removal on PFCs between single-based adsorbent and multiple-based adsorbents was systematically compared and described to determine the execution removal capabilities for each adsorbent. In addition to a detailed review of the published studies, the kinetics and isotherms aspects of PFCs adsorption were reported with various adsorption models, and several adsorption parameters such as the effects of initial PFCs concentration, adsorbent dosage, and temperature on adsorption performance were investigated and the regeneration potential of the adsorbent was also discussed in this article. [ABSTRACT FROM AUTHOR]

Paper is one of the packaging materials that presents a biodegradable character, being used in several areas; however, its barrier properties (gases and fat) and mechanics are reduced, which limits its application. Coating papers with synthetic polymers improve these properties, reducing their biodegradability and recyclability. The objective of this work was to develop and characterize coated paperboard, using the tape casting technique, with different ratios of film form agar–agar/chitosan (AA:CHI, 100:0, 50:50, and 0:100) and different numbers of coating layers (operating times for application of 14.25 min and 28.5 min for one and two layers, respectively). A significant reduction in water absorption capacity was found by applying a 0:100 coating (approximately 15%). Considering all coating formulations, the water vapor permeability reduced by 10 to 60% compared to uncoated paperboard, except for two layers coated with 0:100. The tensile index (independent of AA:CHI) was higher in the machine direction (22.59 to 24.99 MPa) than in the cross-section (11.87–13.01 MPa). Paperboard coated only with chitosan showed superior properties compared to the other formulation coatings evaluated. [ABSTRACT FROM AUTHOR]

Packaging is as important as the product itself because it is a crucial marketing and communication tool for business. Oxidized nanocellulose (ONC), extracted from agriculture residues of bagasse raw material using ecofriendly ammonium persulfate hydrolysis method, is used as support/reducing agent for the generation of silver nanoparticles (AgNPs) via photochemical procedure and reinforcing element in paper functionalization. The natural polymer, sodium alginate (SA) is exploited to enhance the binding of the ONC-AgNPs over cellulose fibers. The SA/ONC-AgNPs bio-nanocomposite is incorporated on paper matrix, which represents a more suitable choice respect to other substrates for its renewable, biocompatible, biodegradable, and cost-effective properties. Structural and antimicrobial evaluations show that the papers embedded with the SA/ONC-AgNPs possess good mechanical, thermal, barrier and antibacterial properties. [ABSTRACT FROM AUTHOR]

Cigarette butts are hazardous to living organisms due to the presence of heavy metal ions that can cause damage to DNA and cells. Chitosan, a natural polymer derived from chitin, has excellent adsorption properties and is a potential solution to this problem. The study aims to develop a chitosan filter and evaluate its ability to remove harmful heavy metals from cigarette butts and investigate the toxicity of chemicals extracted from cigarette butts on human cultured cells. To conduct this study, we quantified the amount of iron (Fe), copper (Cu), mercury (Hg), zinc (Zn), and lead (Pb) in samples of CBEs (cigarette butt extracts). The cytotoxicities of CBE with various concentrations were tested on the human skin cell Detroit 551. Cytotoxicity was also measured with CBE using the chitosan-coated filter. It was made by immersing the Whatman paper filter into a synthesized chitosan solution and drying it. It was then compared with the toxicity of other samples without the filter. Using the chitosan-coated filter, concentrations from the cigarette butt extract decreased in particular heavy metals: Cu (92.1%), Zn (98.2%), and Pb (94.4%). Testing the cytotoxicity of CBEs, the results show a significant decrease in the live cell number starting from 5% CBE. The last experiment showed that 5% CBE with chitosan-coated filter paper, resulting in 1.21 x 106 cells/mL, was more effective in preventing cell deaths compared to non-filtered 5% CBE (0.32 x 106 cells/mL) and filtered 5% CBE (0.21 x 106 cells/mL). These results are significant as it shows how the chitosan-coated filter is a working method to isolate the heavy metals inside cigarette butt extracts and how it can have a positive impact on the environment with future research. [ABSTRACT FROM AUTHOR]

Increased environmental concerns over the use of certain synthetic packaging and coatings in combination with consumer demands for both higher quality and longer shelf life have led to increased interest in alternative packaging materials research. Naturally renewable biopolymers can be used as barrier coatings on paper packaging materials. These biopolymer coatings may retard unwanted moisture transfer in food products, are good oxygen and oil barriers, are biodegradable, and have potential to replace current synthetic paper and paperboard coatings. Incorporation of antimicrobial agents in coatings to produce active paper packaging materials provides an attractive option for protecting food from microorganism development and spread. The barrier, mechanical, and other properties of biopolymer-coated paper are reviewed. Existing and potential applications for bioactive coatings on paper packaging materials are discussed with examples. [ABSTRACT FROM AUTHOR]

Along with the developing of flexible electronics, there is a strong interest in high performance flexible energy storage materials. As natural carbohydrate polymer, cellulose fibers have potential applications in the area due to their biodegradability and flexibility. However, their conductive and electrochemical properties are impossible to meet the demands of practical applications. In this study, cellulose fibers were combined with polyaniline to develop novel paper-based supercapacitor electrode material. Cellulose fibers were firstly coordinated to Cu(II) and subsequently involved in polymerization of polyaniline. Not only the mass loading of polyaniline was significantly increased, but also an impressive area specific capacitance (2767 mF/cm2 at 1 mA/cm2) was achieved. The developed strategy is efficient, environmentally friendly, and has implications for the development of cellulosic paper-based advanced functional materials. [Display omitted] [ABSTRACT FROM AUTHOR]

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Paper coatings based on petroleum-based compounds such as fluoro-compounds, polyethylene, and waxes are utilized to alter the properties of paper, such as wettability and oil and water transport. Although such polymers promote surface water resistance, their unfavorable qualities—poor recycling and lack of biodegradability—have led to their decline. However, using such non-renewable and non-biodegradable materials not only poses a threat to the environment and human health but also releases greenhouse gases. In addition, the use of plastic and fossil-fuel-based materials as barrier coatings in paper-based packaging boxes makes recycling difficult, enhancing overall recycling costs and causing environmental concerns about the waste created due to lack of biodegradation. Due to increasing worries about using petroleum-based polymeric packaging compounds and coatings and rising consumer demands for items with nutritive quality and prolonged shelf life, studies on alternative packaging materials are getting more popular. On the other hand, fresh techniques for environmentally friendly coatings may be constructed by employing biological polymers like polyesters, amino acids, and carbohydrates. These biopolymer coatings are powerful oil and water protectors that can substitute chemical-based paper and paperboard coatings. They could also stop inadvertent water transfer in food products. Nevertheless, many biopolymers may encounter challenges during manufacturing due to the material's innate water-holding capacity, crystallinity, and fragility, which precludes their usage in industrial applications. For that reason, it will be preferable to use polymer blends by combining them with other polymers, fillers, and plasticizers to enhance coating efficacy. This review paper will cover a detailed analysis of the water and oil resistance characteristics of several synthetic and naturally occurring polymers and their composites used as paper coatings for food packaging applications. The combination of polymers and their modifications with various agents and fillers can be utilized to build coatings that enhance the water and oil resistance of papers. There are also discussions about different coating techniques and the various solvents used to prepare coating solutions. [Display omitted] • The oil and water resistance of paper substrates were thoroughly discussed. • Various coating techniques have been discussed. • Applications of the coated papers were discussed. [ABSTRACT FROM AUTHOR]

Partition and diffusion experiments were carried out with paper and board samples coated with different biopolymers. The aim was to evaluate the physicochemical behaviour and barrier properties of bio-coatings against migration of typical contaminants from recycled paper packaging. Focus was directed towards water-based, renewable biopolymers, such as modified starches (cationic starch and cationic waxy starch), plant and animal proteins (gluten and gelatine), poured onto paper with an automatic applicator. Additionally, a comparison with polyethylene-laminated paper was performed. Microstructural observations of the bio-coated paper allowed the characterisation of samples. From the partitioning studies, considerable differences in the adsorption behaviour of the selected contaminants between bio-coated or uncoated paper and air were highlighted. For both the polar and non-polar compounds considered (benzophenone and diisobutyl phthalate, respectively), the lowest values of partition coefficients were found when paper was bio-coated, making it evident that biopolymers acted as chemical/physical barriers towards these contaminants. These findings are discussed considering the characteristics of the tested biopolymers. Diffusion studies into the solid food simulant poly 2,6-diphenyl-p-phenylene oxide, also known as Tenax®, confirmed that all the tested biopolymers slowed down migration. The Weibull kinetic model was fitted to the experimental data to compare migration from paper and bio-coated paper. Values found forβ, an index determining the pattern of curvature, ranged from 1.1 to 1.7 for uncoated and polyethylene paper, whereas for bio-coated papers they ranged from 2.2 to 4.9, corresponding to the presence of an evident lag phase due to barrier properties of the tested bio-coatings. [ABSTRACT FROM PUBLISHER]

In pulp and paper mills, effective biosludge dewatering is essential in wastewater treatment to reduce the large volume of biosludge that needs to be treated and disposed. The dewatering process normally requires the use of polymers from petroleum‐based sources. This study explores the potential of using cationic proteins such as protamine for biosludge dewatering through dual conditioning with a small amount of a synthetic anionic polymer such as anionic polyacrylamide (APAM). The results show that dual conditioning provides substantial synergistic enhancements in dewatering. The maximum cake solids content of biosludge achieved by adding protamine (7.5%) alone was 12%. By dual conditioning with a small amount of APAM (0.1%), not only the cake solids content was increased to 16%, but also the amount of protamine addition was substantially lowered to 2%. These results, coupled with the change in zeta potential of the particles in the biosludge samples, suggest that the cationic protamine reduced the negative charge of the particles, allowing smaller particles to agglomerate and providing a positively charged framework for the subsequent addition of the negatively charged APAM. After adding APAM, substantial floc‐bridging occurred, allowing smaller flocs to aggregate into larger flocs. These synergistic effects can lower the wastewater treatment cost by reducing the amount of synthetic polymer and by applying low‐value proteins from natural sources. [ABSTRACT FROM AUTHOR]

Abstract: In this study, we investigate the “chemical welding” of paper with the ionic liquid (IL) 1-ethyl-3-methylimidazolium acetate ([EMIM]OAc) using a two-step process. First, the IL is transported into the structure of the paper as a water solution. Then, partial dissolution is achieved by activation with heat (80-95 °C), where the water evaporates and the surfaces of the fibres partially dissolve. The activated paper is washed with water to remove IL, and dried to fuse fibre surfaces into each other. The “chemically welded” paper structure has both elevated dry and wet strength. The treatment conditions can be adjusted to produce both paper-like materials and films. The most severe treatment conditions produce films that are fully transparent and their oxygen and grease barrier properties are excellent. As an all-cellulose material, the “chemically welded” paper is fully biodegradable and is a potential alternative to fossil fuel-based plastics.Graphical abstract: [ABSTRACT FROM AUTHOR]

ABSTRACT Biopolymers and their composites were added during the formation of unbleached Kraft bagasse pulp paper sheets to improve the mechanical strength properties of the produced hand sheets. The biopolymers (cellulose, chitosan, and chitosan-cellulose composite) were either crosslinked or noncrosslinked and they were added in series of concentrations from 0.1% to 1.5%. The characterization of the samples using the Fourier transform infrared (IR) technique identified differences in the intensities of the characteristic IR absorption bands for chitosan, cellulose, and their composites, these differences are due to the various degrees of hydrogen bonding. The surface morphology of the biopolymers composites and the treated paper sheets were studied using SEM technique. Both the equilibrium moisture sorption and the diffusion coefficient of the paper sheets containing 1% additives were evaluated at regular time intervals. The long-term stability of the treated paper with biopolymers was verified by exposing the treated and the untreated sheets to hygrothermal ageing. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40761. [ABSTRACT FROM AUTHOR]

Highlights: [•] Paper grade pulp was upgraded to dissolving pulp by two stages of treatment. [•] EG-rich industrial cellulase was used for enzymatic treatment. [•] α-Cellulose content and viscosity can be adjusted by alkali peroxide treatment. [•] Reducing sugar in spent liquor can be recovered to generate value-added products. [Copyright &y& Elsevier]

Cellulosic wastes represent a great environmental challenge, with potential conversion to product-added value through microbial fermentation. Currently, bacterial cellulose (BC) is considered a promising natural polymer for multiple applications. However, the high production cost challenges its wide application. Hence, the current study evaluated the applicability of paper sludge as a cost-effective medium for both cellulases and BC production. The local isolate Streptomyces rochei revealed the highest cellulase production titer (about 3 U/mL) at optimized conditions. For BC production, batch and fed-batch fermentation strategies were evaluated using enzymatically hydrolyzed paper sludge. The results asserted the advantage of fed-batch fermentation for advanced BC production (3.10 g/L) over batch fermentation (1.06 g/L) under the same cultivation conditions. The developed BC membranes were characterized through different instrumental analyses, which revealed an increase in fiber diameters and crystallinity under fed-batch fermentation. Furthermore, BC/magnetite (BC/Fe3O4) nanocomposite was developed by an in-situ approach. The newly developed composite was evaluated for dye removal applications, using methyl orange (MO) as a model. The dye removal conditions were optimized through Box Behnken design (BBD), which indicated maximal MO removal (83.5%) at pH 3.0 and BC/Fe3O4 concentration of 0.1 mg/dL after 60 min. Therefore, the current study asserts the good applicability of enzymatically hydrolyzed paper sludge as a medium for cost-effective BC production and the high capacity of BC/magnetite nanocomposite for MO decolorization. The study paves the way for the cost-effective implementation of BC/magnetite nanocomposite for dye removal. [ABSTRACT FROM AUTHOR]

The degradation of poly(3-hydroxybutyrate- co-4-hydroxybutyrate) (P(3HB- co-4HB)) coated brown Kraft paper and its components in a constructed soil environment was investigated. Soil burial tests were carried out over 8 weeks. Weight loss measurements, photographic analysis, environmental scanning electron microscopy (ESEM), dynamic mechanical analysis (DMA) and differential scanning calorimetry (DSC) were conducted to assess the physical, structural, mechanical and thermal behavior before and after the soil burial test. Paper showed the highest physical degradation and weight loss. With respect to the control samples, the stiffness of the partially degraded samples decreased. The overall crystallinity of the biopolymer and the coated paper was affected significantly by burial. The pure biopolymer's weight loss was substantially enhanced when coated on paper. This result reveals a possible increased microbial population in the coated paper relative to the pure biopolymer. [ABSTRACT FROM AUTHOR]

A natural polymeric material, cellulose nanofibrils (CNFs), that can replace structural additives made of synthetic polymers was studied and characterized. The use of CNFs as a structural additive and the effect of adding them on the basic mechanical parameters of laboratory samples of packaging materials (corrugated sheet, i.e., the intermediate layer of corrugated cardboard) were studied. Addition of a structural additive made of natural renewable raw material to the recycled paper composite for corrugation was shown to increase the key paper quality indicators. [ABSTRACT FROM AUTHOR]

Natural fibers do not have a long life in soil; therefore, they cannot replace synthetic textiles in many applications. However, in order to solve ever-increasing global environmental problems due to microplastics, more and more natural polymers must be used, creating a need for research into the sustainable life extension of natural fibers. Lignin is, along with cellulose, a main component of wood, and is produced in large quantities as waste during paper production. With appropriate processing, lignin can be exploited/used as a textile auxiliary to combine the strength-enhancing properties of textiles made from natural fibers with the protective properties of a lignin coating. However, there is not yet sufficient research on how to integrate lignin into textile applications. For this purpose, in this study, we have investigated whether thermoplastic lignin can be processed as a surface protective coating. We tested lignin as a yarn coating to extend the service life of cellulosic textiles. Cotton yarns have been coated with lignin in variations of coating mass, characterized and investigated by means of soil burial tests. As the soil burial tests conducted in climate chamber and outdoor field environments showed, the lifespan of textiles made from natural fibers can be significantly extended with a lignin coating. Long-term resilience has been demonstrated in standard burial tests. In the outdoor tests, the lignin coating was still fully intact, even after about 160 days of burial. The textile materials coated in this way enable sustainable applications, especially for geotextiles. They have an adjustable, sufficiently long service life; however, they are still biodegradable, and can therefore replace some applications, such as vegetating trench/brook slopes, with synthetic materials. Lignin-coated textiles have the potential to significantly reduce the carbon footprint, reduce not only the dependence on petroleum-based products but also the amount of microplastics entering the environment. Further research can be conducted to improve lignin compounding in terms of other interesting properties for specific textile applications. Process optimization could increase the protective effect and further extend the life of useful textiles in soil. [ABSTRACT FROM AUTHOR]

By exploiting the hydrophilicity of cellulose filter paper (FP) and the excellent chelating property of chitosan (CH) for Mn2+, we have designed an efficient and retrievable dip catalyst MnO 2 /CH-FP for Fenton-like degradation of methylene blue (MB) over a wide pH range from 2.8 to 11.2. The MnO 2 nanoparticles were uniformly immobilized in the CH-FP matrix by in-situ redox precipitation method where Mn(NO 3) 2 was treated with KMnO 4 at mild conditions. A series of MnO 2 /CH-FP hybrids with different MnO 2 loading were fabricated via varying concentration of Mn(NO 3) 2 solution, and their structure-function relationships were discussed based on detailed characterization. The optimal catalyst 1.0MnO 2 /CH-FP could cooperate with multiple low-concentration dosages of H 2 O 2 to efficiently degrade 95.6% MB in 90 min (50 mg L−1 MB, 1 g L−1 catalyst, 30 mg L−1 H 2 O 2 , pH 7). It is also shown that 1.0MnO 2 /CH-FP could still keep 83.3% degradation efficiency of MB after six cycles. Moreover, the activity of this composite greatly surpassed that of bare MnO 2 for nearly 50%, owing to its larger surface area and more accessible active sites. This method for preparing MnO 2 /CH-FP could effectively avoid the agglomeration of MnO 2 nanoparticles and make the reaction turn on/off almost instantaneously by mere insertion/removal. Image 1 • Nano-MnO 2 was in-situ anchored on the biopolymer by redox precipitation method. • It was an efficient and highly retrievable dip catalyst for Fenton-like degradation. • The hybrid has lager surface area and more accessible active sites than bare MnO 2. • The relationship between MnO 2 loading and degradation efficiency was discussed. • Multiple low-concentration doses of H 2 O 2 could achieve better decolorization. [ABSTRACT FROM AUTHOR]

Layer by layer self-assembly techniqueis one of the newest methods to produce multilayer films relying on the placement of the liquid layers on solid substance. The purpose of this studies is to manufacture multilayer kraftbased on protein biopolymers (zein and whey isolate protein) containing of green tea extract phenolic compounds by utilizing layer by layer self- assembly technique and evaluation antibacterial, physical-mechanical properties and release of phenolic compounds from coated kraft at refrigerator temperature inpH of4.5 and 7. The minimum inhibitory concentrationof green tea powder demonstrates thatEscherichia coli (5mg/ml) compared to Listeria monocytogenes (10mg/ml) is more sensitive. The results of physical properties ofkrafts coated paper showed that thickness, grammage and bulk density increased by coating process. Also, the presence of zein in outer layer caused a significant reduction in WVP and increased air resistance. Evaluation of phenolic compounds release from coated krafts demonstrated that release rate in acidic food stimulant was more than the neutral one. Also, release content of kraft paper with zein as outer layers respect to whey isolated protein was higher in the first days and continued in a longer time. Log reduction value of coated kraft with active bilayer zein against Escherichia coli and Listeria monocytogeneswas 0.25 and 0.06 respectively. According to the results of this study, active zein bilayer kraft is recommended as a carrier of phenolic compounds for the packaging of food products. [ABSTRACT FROM AUTHOR]

Chitosan-based electroactive paper has been reported as a smart material, which has merits in terms of lightweight, dry condition, biodegradability, sustainability, large displacement output, and low actuation voltage. However, our recent investigations found its actuation performance is highly sensitive to the membrane thicknesses, both on the electrolyte layer and the electrode layer. Focused on this issue, in this paper, we introduce a biopolymer ionic actuator made by multiwalled carbon nanotube, ionic liquid electrode, and polymer-supported chitosan. As a result, we find that chitosan polymer actuator with the thick electrode layer (0.7 mm) behaves with a larger blocking force (9.66 mN) and a smaller displacement (9.53 mm), and the lifetime under applied voltage of 3 V at 0.25 Hz is 1.75 times surpassed the thin one (0.3 mm). In addition to that, we investigate effects of membrane thicknesses on the electrical properties of chitosan polymer actuator, and figure out the relationship between the tensile strength of the membrane and the volume of the ionic solution in the electrolyte layer. [ABSTRACT FROM PUBLISHER]

Currently, the pulp and paper industry generates around 50–70 million tons of lignin annually, which is mainly burned for energy recovery. Lignin, being a natural aromatic polymer rich in functional hydroxyl groups, has been drawing the interest of academia and industry for its valorization, especially for the development of polymeric materials. Among the different types of polymers that can be derived from lignin, polyurethanes (PUs) are amid the most important ones, especially due to their wide range of applications. This review encompasses available technologies to isolate lignin from pulping processes, the main approaches to convert solid lignin into a liquid polyol to produce bio-based polyurethanes, the challenges involving its characterization, and the current technology assessment. Despite the fact that PUs derived from bio-based polyols, such as lignin, are important in contributing to the circular economy, the use of isocyanate is a major environmental hot spot. Therefore, the main strategies that have been used to replace isocyanates to produce non-isocyanate polyurethanes (NIPUs) derived from lignin are also discussed. [ABSTRACT FROM AUTHOR]

Replacing synthetic polymers with renewable alternatives is a critical challenge for the packaging industry. This research investigated the use of leaf‐based proteins as a sustainable co‐binder in the coating formulations for paper‐based packaging and other applications. Protein isolates from tobacco leaf and alfalfa concentrates were characterized using the Pierce protein assay, Kjeldahl nitrogen, and gel electrophoresis. The proteins were tested as co‐binders in a typical latex‐based paper coating formulation. The rheology and water retention properties of the wet coating and the surface, optical, structural, and strength properties of coated papers were measured. The coating performance was affected by the purity, solubility, and molecular weight of the tobacco protein and exhibited a shear‐thinning behavior with lower water retention than soy protein. Analysis by scanning electron microscopy and time of flight secondary ion mass spectroscopy on the dried coating layer containing tobacco protein showed enhanced porosity (advantageous for package glueability) relative to the control latex coating. The tobacco protein offers adequate coverage and coating pigment distribution, indicating that this protein can be a suitable option in coatings for packaging applications. [ABSTRACT FROM AUTHOR]

This study aimed to characterize biofilms from the paper industry and evaluate the effectiveness of enzymatic treatments in reducing them. The extracellular polymeric substances (EPS) extracted from six industrial biofilms were studied. EPS were mainly proteins, the protein to polysaccharide ratio ranging from 1.3 to 8.6 depending on where the sampling point was situated in the paper making process. Eight hydrolytic enzymes were screened on a 24-h multi-species biofilm. The enzymes were tested at various concentrations and contact durations. Glycosidases and lipases were inefficient or only slightly efficient for biofilm reduction, while proteases were more efficient: after treatment for 24 h with pepsin, Alcalase® or Savinase®, the removal exceeded 80%. Savinase® appeared to be the most adequate for industrial conditions and was tested on an industrial biofilm sample. This enzyme led to a significant release of proteins from the EPS matrix, indicating its potential efficiency on an industrial scale. [ABSTRACT FROM PUBLISHER]

Abstract: Biopolymers have the potential to serve as coating materials for paper to improve its performance properties. The objectives of this study were to determine the effect of hydroxypropyl methylcellulose (HPMC), glycerol (Gly) and beeswax (BW) coatings on the physical properties and water vapor permeability (WVP) of coated papers. It was found that HPMC coated paper showed significant differences on physical properties, compared with uncoated (p ⩽0.05). Folding endurance of HPMC-based coated papers greatly increased which indicated improved durability of coated paper. Moreover, HPMC-based coated papers increased in stretch and decreased in tensile index. HPMC-based coatings reduced WVP and further reduction was obtained when beeswax was incorporated in the HPMC-lipid composite coated paper. Paper coated with hydrocolloid and lipid can be used to produce packages with the potential to be used to maintain agricultural produce quality for the food industry, and may have other applications (i.e., medical packaging). [Copyright &y& Elsevier]