Pulp and paper
Seyed Mehdi Manzour-olajdad; Omid Ramezani
Abstract
Background and Objectives: Our country has been importing various kinds of wallpaper from different countries for many years. With the increase of foreign exchange problems, the local production of wallpaper and its self-sufficiency has been proposed as a suitable solution. On the other hand, currently, ...
Read More
Background and Objectives: Our country has been importing various kinds of wallpaper from different countries for many years. With the increase of foreign exchange problems, the local production of wallpaper and its self-sufficiency has been proposed as a suitable solution. On the other hand, currently, domestic companies are producing paper from white waste paper, which is not justified for use as printing and writing grades due to many problems. However, many companies in the country are producing white grades from white waste paper, the use of which as a base paper in the production of decorative paper or wall paper has not been scientifically investigated. The purpose of this research is to study and investigate the possibility of producing wall paper from recycled white paper produced in the country.Methodology: The stages of this project were carried out in 6 separate and consecutive phases, which include: 1) determining the quality characteristics of the papers; 2) preparation of coating material formulation with starch as binder; 3) preparation of coating material formulation with latex and starch as binder; 4) coating of papers with the prepared coating formulations ; 5) Coating papers and non-woven fabric (Non-Woven) with polyvinyl chloride (PVC); 6) Application of four-color printing on the selected samples of coated papers. For this purpose, first, samples of papers produced by several Iranian companies were acquired and they were transferred to the laboratory of Biosystems and Bioproducts of Shahid Beheshti University for coating and performing the necessary treatments. In order to perform the mentioned treatment on the paper samples, various chemical substances were used, including calcium carbonate powder, kaolin, titanium oxide, corn starch, latex and PVC powder. With this aim, coating solutions with different percentage of solids were prepared steadily and with trial and error using various combinations of these materials (with a total of 110 and 124 parts). Then, these coated solutions were added on various domestic base papers (mostly recycled). Finally, the image of a flower was printed in four colors on the most desirable coated papers.Results: In determining the quality characteristics of base papers, including measurements of water absorption, ash content, thickness, permeability to air, tensile strength, tear resistance index and burst resistance index, two paper samples produced by two companies of Pardis Paper and Tabriz paper were selected as the best and considering the amount of ash, Tabriz paper was introduced as the base paper more suitable than other local papers. Further, after applying the coating material, coated papers with a relatively favorable appearance and whiteness percentages of about 60 to 85 were obtained, and finally, based on the results, a significant relationship was found between the increase in the solids percentage of the coated solutions and the whiteness percentage of the coated paper. Also, after the printing operation on the selected samples, Rasha Superkraft and Tabriz Kraft papers were introduced as the best samples. Also, the highest quality of printing was reached with PVC on Pars white paper with 16% PVC, on whitetop Rasha with 28% PVC and on non-woven fabric (non-woven fabric) with 28% PVC compared to the weight of the paper.Conclusion: The conclusion of the results of this research are listed below:A) The best solid percentage of coating solution (concentration of the mixture) was 41-46%.b) The best combination of binder and pigment, equal to 100 + 12 + 12 = 124 parts and the ratio of the dry weight of the coating mixture added to the dry weight of the base paper is equal to 12%.c) The highest whiteness obtained by adding calcium carbonate + titanium oxide + starch.t) The most suitable concentration of starch that can be used in the coating solution is 15%.c) The best coating and uniform and good coating appearance was obtained on Rasha Superkraft paper with the formula: kaolin + titanium oxide + latex with a whiteness of 77.7% and on Tabriz kraft paper with the formula: kaolin + titanium oxide + latex, with a whiteness of 71.8%. If higher whiteness is desired, using calcium carbonate instead of kaolin would give a better result.
Pulp and paper
Mehrnoosh Tavakoli; Ali Ghasemian; Mohammad Reza Dehghani Firouzabadi; Wojciech Grzeskowiak; Bartłomiej Mazela
Abstract
Background and objectives: The destructive effects of heat increasing in cellulose substrates, which are the basic materials for the packaging industries, high-quality hygiene packaging, and ammunition packaging, are obvious and inevitable. Therefore, it is essential to modify the structure of these ...
Read More
Background and objectives: The destructive effects of heat increasing in cellulose substrates, which are the basic materials for the packaging industries, high-quality hygiene packaging, and ammunition packaging, are obvious and inevitable. Therefore, it is essential to modify the structure of these bio-based products with green and environmentally friendly materials, to increase their durability against heat.Methodology: In the current study, TEMPO-oxidized CNFs and CNCs, were initially and separately retarded using flame retardant mixtures, including dual “ammonium monophosphate+albumin”, “silica+methyltri-methoxysilane”, and quadruple “ammonium monophosphate+albumin+silica+methyltri-methoxysilane”. Using a rod coater, each combination was then coated individually on the produced cellulosic paperboards. Flame retardancy properties were evaluated by three thermal experiments, including a Mini Fire Tube, Limited Oxygen Index, and Mass Loss Calorimeter. Results: Based on the observed results, the role of mono-ammonium phosphate, due to the presence of phosphorus-containing groups as the driving force of the charring during combustion, was more prominent and significant in the dual coating mixture than the quadruple coating mixture, containing silica and phosphorus, both in the paperboards coated based on CNFs and paperboards coated based on CNCs. Comparison of the CNFs and CNCs based-flame retardant, as the main basis of the coating formulation, showed that paperboards coated with CNFs based-flame retardant, due to having amorphous and crystalline regions, had much lower amount of mass loss in the Mini Fire Tube test, almost similar Limited Oxygen Index, and Peak Heat Release Rate (PHRR) and Heat Release Rate (HRR) in the Mass Loss Calorimeter test, compared to those of the paperboard coated with CNCs based-flame retardant. Conclusion: In general, CNFs and CNCs based-flame retardants with mono-ammonium phosphate and albumin, even in low concentrations, can be used as effective retardants and replacements for conventional flame retardants, in high-quality cellulose-based packaging production.
Pulp and paper
Jafar Ebrahimpour Kasmani; Ahmad Samariha; Alireza Khakifirooz
Abstract
This research was conducted with the aim of investigating the effect of two-layer coating of nano-polyurethane and nano-clay on the mechanical and physical properties of packaging cardboard with brown layer. For this purpose, brown layer cardboard with grammage of 127 was prepared and tested. To coat ...
Read More
This research was conducted with the aim of investigating the effect of two-layer coating of nano-polyurethane and nano-clay on the mechanical and physical properties of packaging cardboard with brown layer. For this purpose, brown layer cardboard with grammage of 127 was prepared and tested. To coat the surface of the cardboard, it was first coated with nano-polyurethane and sprayed by a coating nozzle. Then the surface of the brown layer cardboard was covered with nano-clay to improve the performance of the coating material of the first treatment. Nano-clay coating was performed by a laboratory coating machine called barcoter. The coated cardboards were restrained and dried in the room for one day to stabilize the coating material on their surface. Then the samples were placed inside the freezer for 2 and 4 months and their properties were measured. The results showed that coating reduced water absorption. In the coated and frozen samples, an increase in thickness, smoothness of the surface and a decrease in water absorption and resistance properties compared to non-frozen control samples have been observed. Double coated samples showed very few pores. The thickness, smoothness of the surface and resistance to tearing in the machine cross direction of the double coated brown cardboard showed an increase of 13.7%, 75% and 3.8%, respectively, compared to the control sample. water absorption, resistance to bursting, resistance to tearing in the machine direction, resistance to tensile in the machine direction, resistance to tensile in the cross machine direction, resistance to ring crush test in the machine direction and resistance to ring crush test in the cross machine direction of the double-coated brown layer cardboard compared to the control sample, showed 107.20, 1.5, 34.3, 25.4, 24.3, and 4.7 percent decrease respectively.
khadijeh armand; ali ghasemiyan
Abstract
This study was carried out to determine the effect coating polylactic acid-chitosan complex on the packaging paper by two methods of mixing and grafting. For this purpose was made handsheet (80 g/m2) of long fibers that prepared from Mazandaran Wood and Paper Factory. Therefore, poly lactic acid, chitosan ...
Read More
This study was carried out to determine the effect coating polylactic acid-chitosan complex on the packaging paper by two methods of mixing and grafting. For this purpose was made handsheet (80 g/m2) of long fibers that prepared from Mazandaran Wood and Paper Factory. Therefore, poly lactic acid, chitosan and nanocytosis with concentration of 1 wt% , were prepared by dissolving in chloroform and 1% acetic acid, respectively. In both method done coating with three layers. Then, coated samples dried in oven. In the mixing method, polylactic acid and chitosan were mixed then coated 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- Hydoxybenzotriazole) homogeneous solution were prepared and placed on a paper surface. Finally, investigated barrier and mechanical properties including contact angle, water absorption, air permeability and burst strength respectively. The results showed that papers which were coated with grafting method, with three layers of coating (P3nCs3) had the most strength air permeability compared to the mixing method, control sample showed minimum strength to air permeability. Water absorption decreased in coated samples by mixing method compared to grafting method that showed grafting method further reduced water absorption. Contact angle increased in coated samples by the grafting method compared to the mixing method.
rouzbeh asadi khansari; Mohammadreza Dehghani Firouzabadi; Hossein Resalati
Abstract
The purpose of this research is to evaluate the effect of various paper coatings on initial contact angle and its evolution over time. We investigated nine coatings on two types of 75 g and 125 g printing papers. Seven coating compositions containing 80% clay, 20% ground calcium carbonate, dispersing ...
Read More
The purpose of this research is to evaluate the effect of various paper coatings on initial contact angle and its evolution over time. We investigated nine coatings on two types of 75 g and 125 g printing papers. Seven coating compositions containing 80% clay, 20% ground calcium carbonate, dispersing agent and various levels of polyvinyl acetate and lactic acid as binders were used. In the last two coatings, we used 100% precipitated calcium carbonate pigments, cationic starch, methacrylate, dispersant and two levels of cellulose nanofibers. In these suspensions, the amount of cellulose nanofibers in composition 8 is twice composition 9. After coating using rod method, the papers were dried then coated and control samples were calendered. We then performed contact angle measurements using water droplet and Kit No were performed. We noticed largest contact angle and smallest angle change over time for sample 6 containing 75% binder. Last two coatings contained cellulose nanofibers, which caused presence of hydroxyl group on the surface and lowered the contact angle. Composition eight was the most hydrophilic sample. Best barrier property Kit No and largest droplet volume after 20 seconds was accompanied with the increase of the binder percentage in the formulation. For the control sample and three treatments with highest binders, the contact angle over time remains relatively constant which is a sign of hydrophobicity. The correlation between contact angle and volume of the water droplet was determined to be 0.951 and 0.936 in the 75g and 125g papers relatively. We did not notice a significant difference in contact angle and Kit No between 75g and 125g samples.
ali ghasemiyan; khadijeh armand; Elyas Afra; ahmad reza saraeian; mina salary
Abstract
The aim of this study was to investigate the effect of coating packing paper with polylactic acid-chitosan and polylactic acid-nano-chitosan complexes in two layer by layer and composite methods. For this purpose, was used of 80 grams long fiber handsheet paper Prepared from Mazandaran wood and paper ...
Read More
The aim of this study was to investigate the effect of coating packing paper with polylactic acid-chitosan and polylactic acid-nano-chitosan complexes in two layer by layer and composite methods. For this purpose, was used of 80 grams long fiber handsheet paper Prepared from Mazandaran wood and paper factory. For the preparation of coating material, 1% poly lactic acid in chloroform and 1% chitosan and nano chitosan in acetic acid were prepared. In both methods, up to three layers of coating were finally applied and the final layer in each treatment was poly lactic acid. The paper samples were then dried in an oven at a temperature of about 100 ° C. In the composite method, each material (chitosan and nano-chitosan) was mixed independently with poly lactic acid on a magnetic stirrer and then seating on a base paper. Finally, all papers were performed for barrier tests including contact angle measurement, water absorption (Cobb) and water vapor transmission rate (WVTR) and resistance tests including burst resistance and air penetration resistance. Based on the results, the barrier properties of the coated Samples in both methods (layer by layer and composite) were increased compared to the control sample. Also, the results of the study of composite and layer by layer methods showed that the LBL method causes more prohibition in the paper and increases the amount of prohibition with increasing the number of coating layers. It is worth noting, however, that between the second and third layers of coating, changes were less pronounced. These changes were observed in both the LBL and composite methods. Air Resistance was also increased in the coated samples.
Pulp and paper
ali barzan; hossein resalati; ali ghasemian; ahmadreza saraeyan; ghasem asadpour
Abstract
In this study, the effect of pigment composition on the properties of paper prepared from CMP pulp was studied. There for 3 different pigment combinations (100% calcium carbonate (GCC), 70% calcium carbonate and 30% kaolin clay (70GCC30Clay) and 70% calcium carbonate and 25% gritty and 5% titanium dioxide ...
Read More
In this study, the effect of pigment composition on the properties of paper prepared from CMP pulp was studied. There for 3 different pigment combinations (100% calcium carbonate (GCC), 70% calcium carbonate and 30% kaolin clay (70GCC30Clay) and 70% calcium carbonate and 25% gritty and 5% titanium dioxide (70GCC25Clay5TiO2)) were made with anionic starch, latex and dispersersant and Used for coating. Physical properties included (surface roughness of the paper, Ash content and Apparent density) And the optical properties included (brightness, absorption and diffusion coefficient) and paper resistance characteristics including tensile strength, bursting resistance, tear strength based on standard TAPPI standardized measurements and Using factorial design, analysis of variance was performed and the mean of paper properties was compared with Duncan's test. The purpose of this research is to achieve the best combination for coating the paper with the improvement of physical and optical properties and maintaining resistance properties. By adding clay and dioxide titanium to calcium carbonate, the roughness of the paper surface decreased The highest roughness of the surface of the paper in the diet was observed for the control paper and the lowest was seen in the treatment of 70GCC30Clay surface. Also, the highest degree of brightness is related to 70GCC25Clay5TiO2 treatment. The highest index of tensile strength and burst strength index was related to gypsum treated paper (GCC) and also the highest tear strength index for treated paper at level 2 (70GCC30Clay).
Pulp and paper
Bardia Sodeifi; noureddin Nazarnezhad; Seyed Hassan Sharifi
Abstract
DOR:98.1000/1735-0913.1398.34.45.66.1.1576.1610 In this research, the effect of coating with Polycaprolactone (PCL), nanocrystalline Cellulose (NCC) and zinc oxide Nanoparticle (ZnO NP) and their blend were investigated on the mechanical and optical properties. First, coating materials with specific ...
Read More
DOR:98.1000/1735-0913.1398.34.45.66.1.1576.1610 In this research, the effect of coating with Polycaprolactone (PCL), nanocrystalline Cellulose (NCC) and zinc oxide Nanoparticle (ZnO NP) and their blend were investigated on the mechanical and optical properties. First, coating materials with specific condition (PCL 10%, NCC 4 and 6%, ZnO 3%) were coated on the papers. The coating materials weight on the papers was (2.2- 2.7 g/m2). The results showed that the mechanical properties (Tensile strength index, Burst strength index and Tear strength index) of the coated papers were enhanced with addition of NCC. The ternary blend of these coating materials had the best mechanical properties than the neat paper. With addition of NCC the brightness were enhanced and the opacity were reduced. Also, the color properties were improved with addition of NCC and ZnO and the effect of ZnO was more remarkable than NCC but, in ternary blend of materials, the color properties were improved with increasing the amount of NCC.
Management and Economics wood
Seyed Mahmoud Miri Tari; asghar tarmian; Mohammad Azadfallah; Abdolkhani Ali; Davood Efhamisisi
Abstract
DOR:98.1000/1735-0913.1398.34.45.66.1.1575.1575 Mold growth resistance of Polyurethane and Diotrol coatings containing natural (Thyme essential oil) and synthetic (IPBC) fungicides in both free and microencapsulated forms was studied. Polymethyl methacrylate (PMMA) microcapsules were prepared using solvent ...
Read More
DOR:98.1000/1735-0913.1398.34.45.66.1.1575.1575 Mold growth resistance of Polyurethane and Diotrol coatings containing natural (Thyme essential oil) and synthetic (IPBC) fungicides in both free and microencapsulated forms was studied. Polymethyl methacrylate (PMMA) microcapsules were prepared using solvent evaporation method by means of oil emulsion formation in water. Mold growth resistance against Aspergillus niger was determined by Filter Paper Disc method before and after aging process according to ASTM D 5590 Standard. Adhesion strength and surface roughness of coated samples were also measured. Results revealed that biocide-free coatings cannot provide adequate protection against mold growth, and addition of biocides, especially IPBC, significantly improved the mold growth resistance. Even after the aging process, microencapsulated biocides were able to provide better protection against mold growth due to controlled-release mechanism and shielding-effect of polymeric shell. Although the surface roughness of polyurethane coating was increased by using of biocides in both forms, especially microencapsulated ones, its adhesion strength reduced.
Pulp and paper
masoumeh mollaei; Mohammad Azadfallah; Yahya Hamzeh; faramarz khodaian chegini
Abstract
The Effect of Chitosan - Poly (vinyl alcohol) Coatings on Strength and Barrier Properties of Packaging PaperAbstract In this research the mechanical and barrier properties of hand-sheets made of virgin and recycled fibers were studied after coating by chitosan and poly (vinyl alcohol) polymer blends. ...
Read More
The Effect of Chitosan - Poly (vinyl alcohol) Coatings on Strength and Barrier Properties of Packaging PaperAbstract In this research the mechanical and barrier properties of hand-sheets made of virgin and recycled fibers were studied after coating by chitosan and poly (vinyl alcohol) polymer blends. Therefore to evaluate coatings effects on barrier properties, water vapor transmission rate (WVTR), water absorbance, air resistance and grease proof of coated papers were determined. Moreover, mechanical strength including tensile strength and burst strength were measured. According to the results, the barrier properties and mechanical strength of coated papers improved dramatically than uncoated ones. The best results in WVTR and mechanical strength tests were obtained for coatings with the same ratio of polymers. On the other hand, coating with 75%chitosan - 25% poly (vinyl alcohol) composition exhibited excellent resistance against the grease penetration and water absorption.Keywords: Coating, chitosan, poly (vinyl alcohol), barrier properties, mechanical strength