Search

This research explores the potential of agricultural waste, specifically flax straw, as a sustainable raw material for eco-friendly packaging materials. This study investigates a three-stage delignification process involving nitric acid, alkaline treatment, and organosolvent solutions. This method effectively removes lignin from the straw, resulting in high-quality technical pulp with 67.7% α-cellulose and a significantly reduced ash content (8.5%). X-ray diffraction (XRD) and thermogravimetric analysis (TGA) were employed to characterize the treated flax straw. XRD analysis revealed changes in the cellulose structure, while TGA indicated enhanced thermal stability compared to untreated straw. Microscopic analysis of the pulp fibers shows a parallel and aligned arrangement, suggesting a high fiber content and a strong paper lattice. The particle size distribution of the ground pulp, influenced by fiber size, has implications for the packing density and mechanical properties of the final product. This study demonstrates the potential of agricultural waste as a sustainable source for packaging materials, contributing to the circular economy and waste reduction. [ABSTRACT FROM AUTHOR]

In this study, a comparative analysis of silver nanoparticles treatment and chitosan coating on packaging paper barrier properties was carried out. In order to examine the water, grease, and antibacterial barrier properties of silver nanoparticle-treated and chitosan-coated laboratory-obtained paper samples, a mixture of bleached softwood and hardwood celluloses was used. In order to conduct the comparative analysis SEM, water contact angle, Cobb60, and Kit tests were carried out on a cellulose sample, and four paper samples (three of them treated with silver nanoparticles—1, 2, and 3 mL/20 cm2 or chitosan coated—0.5, 1, and 2 g/m2) together with the inhibition activity against nine Gram-positive and Gram-negative bacteria, yeast, and fungal strains. The study found out that increasing the silver nanoparticle treatment and chitosan coating led to improved water resistance, while grease resistance was improved only for chitosan coated paper samples. Additionally, paper treated with 3 mL/20 cm2 of silver nanoparticles had the highest antibacterial protection (81.6%) against the Gram-positive bacterium Staphylococcus aureus, followed by Gram-negative Escherichia coli (75.8%). For the rest of the studied microorganisms, the average efficiency of the treated paper was 40.79%. The treatment of the paper with 1 and 2 mL/20 cm2 of silver nanoparticles was less effective—27.13 and 39.83%, respectively. The antibacterial protection of 2 g/m2 chitosan-coated paper samples was the most effective (average 79%) against the tested bacterial, yeast, and fungal strains. At 1 and 0.5 g/m2 chitosan coatings, the efficiency was 72.38% and 54.67%, respectively. Gram-positive bacteria, yeasts, and fungal strains were more sensitive to chitosan supplementation. [ABSTRACT FROM AUTHOR]

Recycling leather waste, which accumulates in large quantities in tanneries, and producing packaging paper with improved properties reduces the environmental burden and is at the same time economically efficient. A modified fibrous mass of waste from tanned and untanned leather scraps, waste paper, and acrylic emulsion was obtained and packaging paper based on them was produced. Alkaline modification of tanned leather waste - chrome shavings - leads to an increase in the electrokinetic potential and, accordingly, the stability of the fibrous suspension, partial hydrolysis of skin collagen occurs with the formation of new polar groups, and at the same time, the degree of cross-linking of the skin increases. In the paper composition, new intermolecular bonds are formed between cellulose and skin collagen. The microstructure, elemental composition, morphology, thermal and physical-mechanical properties of modified chrome shavings and composite paper were determined. A significant improvement has been achieved in the main parameters of paper: surface density (decrease by 16-25%), breaking load and breaking length (increase by 15-23%), number of double bends (increase by 2-6 times) in comparison with paper obtained from pure waste paper, and also to a greater extent compared to paper obtained from unmodified leather waste.

Nanofibrillated cellulose (NFC) and its combined usage with cationic starch and a cationic copolymer of acrylamide were studied in relation to the properties of paper. Independent pulp treatments using additives separately included 0%, 5%, 10%, and 15% refined long fiber pulp, 3 and 6% NFC, 0.75 and 1.5% cationic starch and 0.07% and 0.15% cationic polyacrylamide and combined treatments. Handsheets were made of the above treatments, and finally their optical and microscopic properties were evaluated. Increasing the NFC content to 6% increased the brightness and yellowness of the white liner by 13% and 21%, respectively. The liner opacity was also reduced by 1%. Additionally, increasing NFC by 6% compared to imported long fibers, the brightness and yellowness of the white liner increased 5.44% and 6.3%, respectively. The liner opacity was also reduced by 1%. A 1.5% cationic starch addition to NFC increased the brightness of the white liner by 4.4%, its whiteness increased 1.5%, and its yellowness increased 2.1%. The opacity of the liner was also reduced by 7.1%. The use of NFC and cationic starch can improve the optical properties of the white liner, while imported long fibers may be problematic.

In the present study, an environmentally friendly oil- and water-resistant paper was developed using a holo-lignocellulosic nanofibril (LCNF)-based composite coating. The LCNF was prepared from wheat straw using a biomechanical method. Characterizations of oil- and water-resistant coated paper and the effect of LCNF content on the performance of the coated paper were confirmed by combining contact angle analysis, Cobb 300s, and mechanical performance tests. The results show that the barrier performance and mechanical strength of the coated paper were greatly improved with the increase of LCNF content. The contact angle of oil and water of coated paper containing 50% LCNF were 69° and 78°, respectively, while the contact angle of oil and water of the base paper were only 30° and 20°, respectively. Cobb 300s values reduced from 110 g/m2 to 30 g/m2 when the LCNF content increased from 50% to 90%. Moreover, under the coating amount of 20 g/m2, the tensile strength of the coating paper was 0.980 KN/m, an increase of 10.11% compared with the base paper. The bursting strength reached 701.930 KPa, which was 10.75% higher than the base paper. In short, it is feasible to prepare LCNF from wheat straw, and apply it to produce water-proof and oil-proof paper. The water-proof and oil-proof paper developed in this study not only offers a novel approach to addressing white pollution but also presents a new research avenue for exploring the potential applications of agricultural waste. [ABSTRACT FROM AUTHOR]

The aim of the present study was to investigate highly efficient alkyl ketene dimer (AKD) emulsions to improve the hydrophobicity of cellulose paper. AKD emulsions stabilized by guar gel were obtained; the guar gel was prepared by hydrogen bond cross-linking sodium tetraborate and guar gum. The cross-linking was confirmed by combining FTIR and SEM. The effect of guar gel on the performance of the AKD emulsions was also studied by testing AKD emulsions stabilized by different guar gel concentrations. The results showed that with increasing guar gel concentration, the stability of the AKD emulsions improved, the droplet diameter decreased, and the hydrophobicity and water resistance of the sized packaging paper were gradually enhanced. Through SEM, the guar gel film covering the AKD emulsion droplet surface and the three-dimensional structure in the aqueous dispersion phase were assessed. This study constructed a scientific and efficient preparation method for AKD emulsions and provided a new method for the application of carbohydrate polymer gels which may avoid the adverse effect of surfactant on paper sizing and environmental problems caused by surfactant bioaccumulation. [ABSTRACT FROM AUTHOR]

Background and objectives: Waste paper recycling utilization has been increasing in Iran and world paper industries which offers many benefits to the environment and humans. Municipal waste is also reused after recycling processes. Cardboard recycling industry has great environmental and economic importance and helps overcone the lack of wood resources and high demand for paper products. It plays an important role in the development of paper-related industries. However, recycling can be associated with the reduction in the optical properties of the paper. The use of nanoparticles in the paper industry is also expanding gradually. Nanosilica is one of the most important nanoparticles which is used as a retention aid in the paper industry. In order to reduce the consumption of long fibers and obtain the desired optical properties, the use of nanosilica alone or in combination with other materials such as cationic starch and cationic polyacrylamide is investigated. The purpose of this research is to compare the effect of individual and combined use of nanosilica additives, cationic polyacrylamide, cationic starch and long fibers on the optical properties of white liner paper pulp. Methodology: In this study, white paper pulp with the brightness of at least 78% and the gloss of at least 45% was used to prepare handmade paper sheets. Long fiber kraft chemical pulp from coniferous wood imported from Russia with the brightness of 89% was used in the laboratory paper sheet making. Nanosilica powder (NanoSiO2) (Degussa), Germany, cationic polyacrylamide (Farinret K325 brand, Degussa, Germany), and cationic starch (LyckebyAmylex, Slovakia) were used. Independent treatments included the addition of 10% refined long fibers pulp, 6% nanosilica, 1.5% cationic starch and 0.15% cationic polyacrylamide and combined treatments included 6% nanosilica and 1.5% cationic starch and 6% nanosilica and 0.15% cationic polyacrylamide. Then 127 g.m-2 handmade papers were prepared and the optical and microscopic properties were evaluated. Results: The results showed that by adding 10% long fibers, the brightness decreased and by using 6% nanosilica, the maximum brightness was reached. Meanwhile, the whiteness of papers with 6% nanosilica was minimum and with the dosage of only 0.15% cationic polyacrylamide, the whiteness reached at the maximum value. Opacity showed its highest value with the combination of 6% nanosilica and 0.15% cationic polyacrylamide. Also, by increasing the amount of polyacrylamide and cationic starch, individually or in combination with nanosilica, the opacity increased. The light absorption coefficient was the lowest in papers with 6% nanosilica and the light scattering coefficient was the highest in papers containing 6% nanosilica and 0.15% cationic polyacrylamide. A colorimeter was used to measure the color components and the results showed that the additives had an effect on the brightness and whiteness of the papers. Also, changes in the color spectrum and the value of color change were also observed. Additives increased the darkness and changes in different colors. Conclusion: The use of nanosilica individually and in combination with starch and cationic polyacrylamide increases the brightness of papers. Also, the use of cationic polyacrylamide individually and in combination with nanosilica leads to an increase in the whiteness and opacity of papers. The brightness factor of the papers, which is representative of the L* component, decreased with the exception of the addition of 10% long fibers and 6% nanosilica. The amount of overall color change with ΔE* was the lowest in samples containing 1.5% cationic starch and the highest in samples containing 0.15% cationic polyacrylamide. The use of some treatments can lead to a decrease in the optical properties and a decrease in the printability quality of the white liner. To solve this problem, mechanical pulp that has been decolorized or coated on the surface of the paper can be used. The presence of nano-silica particles in the structure of the paper improves the surface structure and reduces the prosity, which results in the reduction of surface roughness and less light refraction, and increases the light reflection and brightness of the paper. [ABSTRACT FROM AUTHOR]

In this study, a comparative analysis of silver nanoparticles treatment and chitosan coating on packaging paper barrier properties was carried out. In order to examine the water, grease, and antibacterial barrier properties of silver nanoparticle-treated and chitosan-coated laboratory-obtained paper samples, a mixture of bleached softwood and hardwood celluloses was used. In order to conduct the comparative analysis SEM, water contact angle, Cobb60, and Kit tests were carried out on a cellulose sample, and four paper samples (three of them treated with silver nanoparticles—1, 2, and 3 mL/20 cm2 or chitosan coated—0.5, 1, and 2 g/m2) together with the inhibition activity against nine Gram-positive and Gram-negative bacteria, yeast, and fungal strains. The study found out that increasing the silver nanoparticle treatment and chitosan coating led to improved water resistance, while grease resistance was improved only for chitosan coated paper samples. Additionally, paper treated with 3 mL/20 cm2 of silver nanoparticles had the highest antibacterial protection (81.6%) against the Gram-positive bacterium Staphylococcus aureus, followed by Gram-negative Escherichia coli (75.8%). For the rest of the studied microorganisms, the average efficiency of the treated paper was 40.79%. The treatment of the paper with 1 and 2 mL/20 cm2 of silver nanoparticles was less effective—27.13 and 39.83%, respectively. The antibacterial protection of 2 g/m2 chitosan-coated paper samples was the most effective (average 79%) against the tested bacterial, yeast, and fungal strains. At 1 and 0.5 g/m2 chitosan coatings, the efficiency was 72.38% and 54.67%, respectively. Gram-positive bacteria, yeasts, and fungal strains were more sensitive to chitosan supplementation.

In the present study, an environmentally friendly oil- and water-resistant paper was developed using a holo-lignocellulosic nanofibril (LCNF)-based composite coating. The LCNF was prepared from wheat straw using a biomechanical method. Characterizations of oil- and water-resistant coated paper and the effect of LCNF content on the performance of the coated paper were confirmed by combining contact angle analysis, Cobb 300s, and mechanical performance tests. The results show that the barrier performance and mechanical strength of the coated paper were greatly improved with the increase of LCNF content. The contact angle of oil and water of coated paper containing 50% LCNF were 69° and 78°, respectively, while the contact angle of oil and water of the base paper were only 30° and 20°, respectively. Cobb 300s values reduced from 110 g/m2 to 30 g/m2 when the LCNF content increased from 50% to 90%. Moreover, under the coating amount of 20 g/m2, the tensile strength of the coating paper was 0.980 KN/m, an increase of 10.11% compared with the base paper. The bursting strength reached 701.930 KPa, which was 10.75% higher than the base paper. In short, it is feasible to prepare LCNF from wheat straw, and apply it to produce water-proof and oil-proof paper. The water-proof and oil-proof paper developed in this study not only offers a novel approach to addressing white pollution but also presents a new research avenue for exploring the potential applications of agricultural waste.

The alarming global deforestation rate has great impacts on the output of the Pulp and paper Industry since wood is the principal papermaking fiber material. Although, generally, bamboo is an alternative cellulolytic fiber source, the species and culm age have great effects on its papermaking potential. Based on the methods by the International Association of Wood Anatomists (IAWA), this work assessed the characteristics of fibers from the axial culm sections of six-month plantation-grown Oxythenantera abyssinica and Beema bamboo (which was cloned from Bambusa balcoaa) for paper production. The lengths of the fibers ranged from 1.89 to 2.39 mm while the diameters were 0.025–0.031 mm. The fiber lumen diameter and wall thickness were 0.014–0.018 mm and 0.004–0.006 mm, respectively. Fibers from the species had their runkle ratios below 1, slenderness ratios above 70 and flexibility ratios above 50. These characteristics compare well with the recommendations for fibers often used for the production of packaging, writing and printing papers. Establishment of plantations of Beema bamboo and O. abyssinica is encouraged as they will serve as good raw material base for the paper industry within six months of planting. Additionally, their planting will contribute to meeting Sustainable Development Goals 1 and 13.

The aim of the present study was to investigate highly efficient alkyl ketene dimer (AKD) emulsions to improve the hydrophobicity of cellulose paper. AKD emulsions stabilized by guar gel were obtained; the guar gel was prepared by hydrogen bond cross-linking sodium tetraborate and guar gum. The cross-linking was confirmed by combining FTIR and SEM. The effect of guar gel on the performance of the AKD emulsions was also studied by testing AKD emulsions stabilized by different guar gel concentrations. The results showed that with increasing guar gel concentration, the stability of the AKD emulsions improved, the droplet diameter decreased, and the hydrophobicity and water resistance of the sized packaging paper were gradually enhanced. Through SEM, the guar gel film covering the AKD emulsion droplet surface and the three-dimensional structure in the aqueous dispersion phase were assessed. This study constructed a scientific and efficient preparation method for AKD emulsions and provided a new method for the application of carbohydrate polymer gels which may avoid the adverse effect of surfactant on paper sizing and environmental problems caused by surfactant bioaccumulation.

Food packaging manufacturers often resort to lamination, typically with materials which are neither non-biodegradable nor biobased polymers, to confer barrier properties to paper and cardboard. The present work considers a greener solution: enhancing paper's resistance to moisture, grease, and air by aqueous coating suspensions. For hydrophobization, a combined approach between nanocellulose and common esterifying agents was considered, but the water vapor transmission rate (WVTR) remained excessively high for the goal of wrapping moisture-sensitive products (>600 g m−2 d−1). Nonetheless, oil-repellant surfaces were effectively obtained with nanocellulose, illite, sodium alginate, and/or poly(vinyl alcohol) (PVA), reaching Kit ratings up to 11. Regarding air resistance, mineral-rich coatings attained values above 1000 Gurley s. In light of these results, nanocellulose, minerals, PVA, pullulan, alginate, and a non-ionic surfactant were combined for multi-purpose coating formulations. It is hypothesized that these materials decrease porosity while complementing each other's flaws, e.g., PVA succeeds at decreasing porosity but has low dimensional stability. As an example, a suspension mostly constituted by nanocellulose, sizing agents, minerals and PVA yielded a WVTR of roughly 100 g m−2 d−1, a Kit rating of 12, and an air resistance above 300 s/100 mL. This indicates that multi-purpose coatings can be satisfactorily incorporated into paper structures for food packaging applications, although not as the food contact layer. [ABSTRACT FROM AUTHOR]

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

This study was carried out to determine the effect coating with polylactic acid-chitosan complex on the packaging paper by two methods of mixing and grafting. For this purpose, handsheet (80 g/m2) was made using long fibers collected from Mazandaran Wood and Paper Factory. Poly lactic acid, chitosan and nanocytosis with the concentration of 1 wt. %, were prepared by dissolving in chloroform and 1% acetic acid, respectively. In both methods, three layers coating was applied. Then, coated samples were dried in oven. In the mixing method, polylactic acid and chitosan were mixed and then applied on base paper. In the grafting method, by chemical modification of chitosan and polylactic acid, 0.01 g of EDC (N-(3-dimethy laminopropyl)-N/-ethylcarbodiimide hydrochloride), 0.1 g of Span 80 and 0.047 g of HOBT ( 1- Hydoxy benzotriazole) homogeneous solution were prepared and applied on a paper surface. Finally, barrier and mechanical properties including contact angle, water absorption, air permeability and burst strength were measured respectively. The results showed that papers which were coated with grafting method, using three layers of coating (P3nCs3) had the highest air permeability resistance compared to the mixing method. Control sample showed minimum air permeability resistance. Water absorption decreased in coated samples by mixing method compared to grafting method and grafting method further reduced water absorption. Contact angle increased in coated samples by the grafting method compared to the mixing method.

The predicted scarcity of wood-based fibre supplies has necessitated the search for alternative sources including non-woods by paper manufacturers. As a raw material for pulping, hemp bast fibre has some potential. To provide a guide for the pulp and paper industries, the suitability of hemp bast fibres for the pulp and paper industries was evaluated in this study, and blending trials with wastepaper pulp were conducted. In the hemp bast fibre preparation, the length of the fibres was first reduced to 4 mm. Subsequently, kraft pulping was applied to them. Along with the preparation of wastepaper pulps, hemp bast fibres and wastepaper handsheets were prepared according to a blending plan. Finally, the handsheets were subjected to paper strength tests. The properties of raw, cooked and beaten hemp bast fibres were investigated by characterisation methods such as optical microscopy, X-ray diffraction and Fourier-transform infrared spectroscopy. Additionally, carbohydrate components, solubility and ash content tests were run on raw hemp bast fibres. As a result of the experiments and analyses, the targeted results were achieved. Following the resolution of the fibrillation problem, it was determined that hemp bast fibre pulp can be used in adequate blends of wastepaper pulp when the strength values of the end product are desired to be increased (including CMT, CCT, RCT, SCT, stiffness and tear resistance) or decreased (air resistance). [ABSTRACT FROM AUTHOR]

In the packaging sector of the printing industry, different coating applications are tried and investigated in order to increase the surface appearance and performance characteristics of paper and cardboard. The printability, water and ink absorption capacity, frictional resistance, light sensitivity of the visual graphical design that are going to be printed on the packaging papers are some of them. In this study, different types of cardboards that are used as a packaging material were chosen and coated with nanocrystalline cellulose (NCC)/PVA at different rates (%). In order to determine effective and economical usage conditions, the coating solutions, at three different concentrations as 3 wt.%, 5 wt. %, 7 wt.%, were prepared. The coating was applied on the test papers, which were at the same weights (350 g/m2) and had different surface properties as matte glossy, bright glossy, American Bristol. NCC/PVA existence on the coated paper surface was confirmed with Fourier Transform Infrared Spectroscopy (ATR-FTIR). The impact of the coating, which was prepared at different concentrations, on the packaging materials was studied with respect to thickness, stiffness, water absorbability, contact angle and surface tension.

The paper presents the research results on the properties of the pulp coniferous and deciduous wood composition in its original state and paper made from it, proposes a mechanism to increase the waterfast and waterproof food packaging paper by surface treatment with a composition based on polyamidepichlorohydrin with polyvinyl alcohol and urea. The study was conducted in order to ensure an increase in the consumer properties of packaging paper, since when packaging materials encounter food products, their structure can change under the influence of moisture, steam, and gas. Polyamidaminepichlorohydrin was used as the main component of the composition for paper processing, as functional additives: polyvinyl alcohol and urea. The above-mentioned starting materials are environmentally friendly, since foreign inclusions in food packaging materials would pose a serious danger to human health and life, as well as to the brand image of the product in which they would be detected. It was proved that high waterfastness and waterproofness, as well as the necessary level of barrier, protective and operational properties of packaging material for food products cannot always be obtained by introducing a significant amount of polyamidaminepichlorohydrin, so the paper investigated the mechanism of interacting cellulose fibers of paper with polyamidaminepichlorohydrin, and also proved the possibility of its use to obtain packaging paper with a given set of properties. It was found that the consumption of up to 4–6% polyamidaminepichlorohydrin provides the main increase in the mechanical strength of packaging paper, both in wet and dry conditions. The resulting waterfast and waterproof material can be used for food packaging.

The paper presents the research results on the properties of the pulp coniferous and deciduous wood composition in its original state and paper made from it, proposes a mechanism to increase the waterfast and waterproof food packaging paper by surface treatment with a composition based on polyamidepichlorohydrin with polyvinyl alcohol and urea. The study was conducted in order to ensure an increase in the consumer properties of packaging paper, since when packaging materials encounter food products, their structure can change under the influence of moisture, steam, and gas. Polyamidaminepichlorohydrin was used as the main component of the composition for paper processing, as functional additives: polyvinyl alcohol and urea. The above-mentioned starting materials are environmentally friendly, since foreign inclusions in food packaging materials would pose a serious danger to human health and life, as well as to the brand image of the product in which they would be detected. It was proved that high waterfastness and waterproofness, as well as the necessary level of barrier, protective and operational properties of packaging material for food products cannot always be obtained by introducing a significant amount of polyamidaminepichlorohydrin, so the paper investigated the mechanism of interacting cellulose fibers of paper with polyamidaminepichlorohydrin, and also proved the possibility of its use to obtain packaging paper with a given set of properties. It was found that the consumption of up to 4–6% polyamidaminepichlorohydrin provides the main increase in the mechanical strength of packaging paper, both in wet and dry conditions. The resulting waterfast and waterproof material can be used for food packaging. [ABSTRACT FROM AUTHOR]

The expediency of using a sunflower as an alternative raw material for the cellulose and paper industry and peroxyacetic acid as a cooking solution of a plant material is substantiated. The catalytic action of Na2WO4, Na2MoO4 and TiO2 on the process of delignification of sunflower stalks with hydrogen peroxide in the acetic acid was studied. The resulting peracetic cellulose with sodium tungstate has high quality indices. The indices of the lignin extraction selectivity by per oxoacetic delignification of sunflower stalks are calculated. The paper-making properties of the organic solvent cellulose from sunflower stalks are determined. The possible usage in the production of packaging paper has been evaluated. [ABSTRACT FROM AUTHOR]

This study was carried out to determine the effect coating with polylactic acid-chitosan complex on the packaging paper by two methods of mixing and grafting. For this purpose, handsheet (80 g/m²) was made using long fibers collected from Mazandaran Wood and Paper Factory. Poly lactic acid, chitosan and nanocytosis with the concentration of 1 wt. %, were prepared by dissolving in chloroform and 1% acetic acid, respectively. In both methods, three layers coating was applied. Then, coated samples were dried in oven. In the mixing method, polylactic acid and chitosan were mixed and then applied on base paper. In the grafting method, by chemical modification of chitosan and polylactic acid, 0.01 g of EDC (N-(3-dimethy laminopropyl)-N/-ethylcarbodiimide hydrochloride), 0.1 g of Span 80 and 0.047 g of HOBT (1-Hydoxy benzotriazole) homogeneous solution were prepared and applied on a paper surface. Finally, barrier and mechanical properties including contact angle, water absorption, air permeability and burst strength were measured respectively. The results showed that papers which were coated with grafting method, using three layers of coating (P3nCs3) had the highest air permeability resistance compared to the mixing method. Control sample showed minimum air permeability resistance. Water absorption decreased in coated samples by mixing method compared to grafting method and grafting method further reduced water absorption. Contact angle increased in coated samples by the grafting method compared to the mixing method. [ABSTRACT FROM AUTHOR]

In the packaging sector of the printing industry, different coating applications are tried and investigated in order to increase the surface appearance and performance characteristics of paper and cardboard. The printability, water and ink absorption capacity, frictional resistance, light sensitivity of the visual graphical design that are going to be printed on the packaging papers are some of them. In this study, different types of cardboards that are used as a packaging material were chosen and coated with nanocrystalline cellulose (NCC)/PVA at different rates (%). In order to determine effective and economical usage conditions, the coating solutions, at three different concentrations as 3 wt.%, 5 wt. %, 7 wt.%, were prepared. The coating was applied on the test papers, which were at the same weights (350 g/m2) and had different surface properties as matte glossy, bright glossy, American Bristol. NCC/PVA existence on the coated paper surface was confirmed with Fourier Transform Infrared Spectroscopy (ATR-FTIR). The impact of the coating, which was prepared at different concentrations, on the packaging materials was studied with respect to thickness, stiffness, water absorbability, contact angle and surface tension. [ABSTRACT FROM AUTHOR]

The poor barrier properties and hygroscopic nature of cellulosic paper impede the wide application of cellulosic paper as a packaging material. Herein, a polyvinyl alcohol (PVA)-based polymer coating was used to improve the barrier performance of paper through its good ability to form a film. Alkyl ketene dimer (AKD) was used to enhance the water resistance. The effect of the absorptive characteristics of the base paper on the barrier properties was explored, and it was shown that surface-sized base paper provides a better barrier performance than unsized base paper. Nanoclay (Cloisite Na+) was used in the coating formulation to further enhance the barrier performance. The results show that the coating of PVA/AKD/nanoclay dispersion noticeably improved the barrier performance of the paper. The water vapor transmission rate of the base paper was 533 g/m2·day, and it decreased sharply to 1.3 g/m2·day after the application of a double coating because of the complete coverage of the base paper by the PVA-based polymer coating. The coated paper had excellent water resistance owing to its high water contact angle of around 100°. The grease resistance and mechanical properties of the base paper also improved after coating. This work may provide inspiration for improving the barrier properties of packaging paper through the selection of a suitable base paper and coating formulation.

Nanotechnology applied to pulp and paper sector enables production of nanostructured papers with excellent strength properties. The addition of lignocellulose nanofibrils (LCNF) to traditional kraft pulps is an attractive alternative for production of improved packaging papers. In relation to cellulose nanofibrils (CNF), LCNF application in unbleached papers has the advantage of eliminating the costs of bleaching chemicals and potential advantages in drainage. One aim of this study was producing and characterizing LCNF from eucalypt (E) and pine (P) unbleached pulps and comparing the results with the traditional CNF. Another aim of the work was evaluating LCNF as an additive for production of kraftliner and sackraft nanostructured packaging papers. LCNF proved to be a viable additive for the production of high-strength nanostructured papers while relying on low energy consumption during the refining process. LCNF addition had positive effects on the mechanical properties of the nanostructured papers produced, resulting in significant increases in strength properties. [ABSTRACT FROM AUTHOR]

Elongation is an important property of many packaging board and paper grades. Paper with high extensibility could provide an alternative for oilbased packaging materials. Micro- (CMF) and nanofibrillated (CNF) cellulose are known to increase the strength of a paper, but their effect on the drying shrinkage and elongation is not well-studied. In this work, paper was reinforced with fibrillated material. Added fibrillated material increased the drying shrinkage, which was generally proportional to the increase of paper elongation before breakage. Results differed depending on the fibrillated material and how it was added to paper (wet-end addition or spray application). The papers were dried unrestrained in order to achieve the highest elongation potential for the paper. Spray application of CMF increased elongation by 13%, while wet-end additions increased elongation by 20% and also strength by 10%, but only with high dosages. Spray application of oxidized-CNF improved elongation by 33%, while wetend applications increased only strength by 20%. Thus, boosting the drying shrinkage with fibrillated cellulose is one potential way to increase elongation and 3D formability of paper. [ABSTRACT FROM AUTHOR]

Hydrophobic noncrystalline porous starch (NCPS) containing microporous and amorphous structures was prepared from native corn starch via heat treatment, solvent exchange, and alkyl ketene dimer (AKD) modification. Then, antibacterial packaging was produced by combining silver nanoparticles with the hydrophobic NCPS (hydrophobic NCPS/Ag) and employing this biobased coating as a layer on the base paper. The antibacterial activity, strength, and barrier properties of the hydrophobic NCPS/Ag-coated paper were measured. In addition, the fine porous surface of NCPS, the distribution of the silver nanoparticles in hydrophobic NCPS as well as the network structure of uncoated paper and coated paper were characterized by scanning electron microscopy. Meanwhile, the hydrophobicity of the corn starch, hydrophobic NCPS, uncoated paper, and coated paper were determined using water contact angles. The silver nanoparticles had a positive effect on the antibacterial activity against Escherichia coli and Staphylococcus aureus. The air permeability, oil resistance, water vapor transmission rate, water absorption, whiteness, tensile strength, and burst strength improved compared to the uncoated paper. [ABSTRACT FROM AUTHOR]

This study reports on the development of bio-based hydrophobic coatings for packaging papers through deposition of polyhydroxybutyrate (PHB) particles in combination with nanofibrillated cellulose (NFC) and plant wax. In the first approach, PHB particles in the micrometer range (PHB-MP) were prepared through a phase-separation technique providing internally-nanosized structures. The particles were transferred as a coating by dip-coating filter papers in the particle suspension, followed by sizing with a carnauba wax solution. This approach allowed partial to almost full surface coverage of PHB-MP over the paper surface, resulting in static water contact angles of 105°-122° and 129°-144° after additional wax coating. In the second approach, PHB particles with submicron sizes (PHB-SP) were synthesized by an oil-in-water emulsion (o/w) solvent evaporation method and mixed in aqueous suspensions with 0-7 wt % NFC. After dip-coating filter papers in PHB-SP/NFC suspensions and sizing with a carnauba wax solution, static water contact angles of 112°-152° were obtained. The intrinsic properties of the particles were analyzed by scanning electron microscopy, thermal analysis and infrared spectroscopy, indicating higher crystallinity for PHB-SP than PHB-MP. The chemical interactions between the more amorphous PHB-MP particles and paper fibers were identified as an esterification reaction, while the morphology of the NFC fibrillar network was playing a key role as the binding agent in the retention of more crystalline PHB-SP at the paper surface, hence contributing to higher hydrophobicity. [ABSTRACT FROM AUTHOR]

Paper and ink characteristics effect on print density were investigated. For this purpose three types of papers and four types of printing inks at 2 viscosities levels (25-30, 50-55) were used. Then characteristics of paper & ink were measured. Inks on sampled papers Printed and then printing density was measured. Statistical analysis was conducted based on a complete randomized design in factorial experimental model and means were analyzed and grouped by Duncan multiple range test (DMRT) using SPSS software. Result indicated that Solid content, pH and particles diameter of inks have significant effect on print density. While roughness and water absorption of papers do not have on significantly influences print density. There was not any significant different between two viscosity level and print density

Effect of roughness & water absorption of paper and ink characteristics on optical properties was investigated. For this purpose three type of paper and four type of printing ink was used.Then characteristics of paper & ink was measured. Inks on sampled papers Printed and then L, a & b was measured. Result indicated that the effect of roughness and water absorption on L, a & b are not significant. But Solid content, PH and particles diameter of four type of ink on L, a & b have significant effect