Softwood Bleached Pulp Research Articles

Effect of unbleached and bleached softwood cellulose pulp fibers on poly(lactic acid) properties

Global regulations are guiding society towards more sustainable material solutions. This increasing awareness of the need for environmentally friendly alternatives has led to a greater emphasis on biocomposites, which combine natural fibers with bio-based polymers. This study investigates how bleached softwood pulp fibers (BSWPF) and unbleached softwood pulp fibers (UBSWPF) affect the characteristics of poly(lactic acid) (PLA)-based biocomposites. UBSWPF is a more cost-effective option because it is manufactured with less processing steps than BSWPF. However, it is largely unexplored as a reinforcement in biopolymers. Through investigating the mechanical, thermal, and morphological aspects of the biocomposites, this study showed that UBSWP increased the modulus and impact strength of the PLA biocomposites better than BSWPF. The impact strength, modulus, and tensile strength of PLA-BSWPF and PLA-UBSWPF improved as the fiber content increased. However, a decrease in tensile strength was seen at higher percentages of UBSWPF in PLA. Despite the decrease in tensile strength at higher UBSWPF concentrations, both types of fibers improved the mechanical properties of the biocomposites, demonstrating a potential sustainable reinforcing material for PLA biocomposites.

Enzyme-assisted dewatering and strength enhancement of cellulosic fibers for sustainable papermaking: A bench and pilot study

Water removal during paper manufacturing is of primary importance to production rate and cost efficiency for the pulp and paper industry. It is crucial to develop methods to reduce energy consumption by increasing the percent solids in the paper web entering the dryers from the presses. This research aimed to develop a fundamental understanding of the effect of bio-chemo-mechanical pretreatments on a bleached softwood fiber matrix and evaluate the impact on the percent solids of the paper web after pressing. Experiments included enzymatic, refining, and cationic polymer pretreatments on the bleached softwood pulps, followed by laboratory papermaking and determining the equilibrium moisture content (EMC) after pressing and the pulp and paper properties. The combined effect of mild refining, controlled enzymatic pretreatments, and cationic strength aids proved to enhance the water removal during wet pressing (up to 35 % reduction) and increase paper strength (up to 60 % increase). The results of increased solids after pressing were used to calculate the potential reduction in drying energy during paper manufacturing. Energy savings of around 10 % for paper drying could be achieved through fiber matrix modification by bio-chemo-mechanical pretreatment. Enzymatic pretreatments have previously been conventionally applied before refining as an energy-saving method. However, this research shows that synergistic actions of enzymes added after refining modify the fibers and create the optimal conditions for enhancement in drainage, press dewatering, and paper properties.

Zeolitic imidazolate framework-67 enabled cellulosic paper for efficient particulate matter capture

The combination of functional zeolitic imidazolate frameworks (ZIFs) with suitable substrates is promising for the preparation of advanced filtering materials. In this study, the bleached kraft softwood pulp (NBKP) was composited with ZIF-67 particles via an in situ growth method to fabricate functional paper. Enabled by the traditional papermaking process, ZIF-67 crystals were uniformly and tightly anchored on cellulosic fibers in a facile and economic way. The introduction of ZIF-67 boosted the mechanical performances of the composite paper owing to the presence of electrostatic interactions and hydrogen bonds. Meanwhile, the resultant paper presents hierarchical porous structure with a large specific surface area of 327.07 m2·g−1. The filters with hierarchical pore structure will provide a complex tortuous channel for passing particulates, which can increase the frequency of effective collision between filters and particulates. Air filtering tests demonstrated that the ZIF-67 entrapped paper has superior particle removal efficiency with a low pressure drop and a large dust holding capacity. The optimal ZP-3 sample displayed removal efficiencies of 98.52 % for PM2.5 and 99.00 % for PM10. Meanwhile, filtration quality factors were calculated to be 0.15 (PM2.5) and 0.17 (PM10), respectively. The filter also has good antibacterial activity. In addition, ZP-x composite paper is easy to regenerate and possesses good reusability. The high-efficient ZP-x filter will have potential applications in fields of air purification.

Photosensitive cellulosic materials based on a covalently grafted phenosafranin-modified silsesquioxane analog for bactericidal applications

Light-triggered antimicrobial cellulose surfaces were obtained by the immobilization of a photosensitive phenosafranin dye (PSF) in a hybrid organic–inorganic silsesquioxane polymer applied on handsheets prepared from a standard bleached softwood pulp. These coatings were deposited by polycondensation of methyltriethoxysilane and an alkoxysilyl derivative of phenosafranin (TESPSF) obtained by the thiolene addition reaction and coupling of the succinic anhydride derivative with a primary amine group of PSF. TESPSF and coatings were characterized by advanced techniques in terms of chemical structure (1H, 13C, 29Si NMR, MS, ATR-IR), surface properties (SEM, EDX, water contact angles), and optical properties (UV, reflection light intensity, ISO brightness). The light-induced antimicrobial activity of sheets of paper coated with new materials showed the inhibition of the growth of the bacteria Staphylococcus aureus ATCC 6538 and Escherichia coli ATCC 8739. The cytotoxicity studies of modified cellulose surfaces were performed using erythrocyte lysis assays under both dark and light conditions exhibited no toxicity on erythrocytes. Thus, the new material did not reveal harmful effects on erythrocytes, regardless of the presence and absence of light.

Thermal-degradation characteristics of mechanically nanofibrillated bleached pulps from hardwood and softwood

Nanofibrillated cellulose (NFC) consists of ultrafine cellulose structures in which the fibrils can have widths in the range from about 5 to 100 nm. NFC has been studied and developed in the paper industry, using bleached pulp from wood as the raw material. One of the issues in the application of NFC is their heat resistance to thermal degradation. The production process of NFC results in a decrease in their pyrolysis temperature during the nanofibrillation of bleached pulp; however, the details behind the reason and mechanisms are still unclear. In this study, NFC was prepared from bleached hardwood and softwood pulp by mechanical nanofibrillation using a grinder, and the pyrolysis behavior was investigated. For both bleached pulps, a decrease in the pyrolysis temperature was observed after nanofibrillation. The results suggest that the decrease in the pyrolysis temperature from nanofibrillation is not due to damage of the crystalline cellulose by nano fibrillation, but the damage of the hemicellulose components in the surface of the cellulose microfibrils or the interface between the crystalline cellulose and hemicellulose. If the hemicellulose on the surface of crystalline cellulose could be removed from the NFC, then the decrease in the pyrolysis temperature could be suppressed.

Influence of temperature and pressure during thermoforming of softwood pulp

In this study, the influence of thermoforming conditions on the resulting material properties was investigated, which aimed at developing advanced wood-fiber-based materials for the replacement of fossil plastics. Two bleached softwood pulps were studied, i.e., northern bleached softwood Kraft pulp (NBSK) and chemi-thermomechanical softwood pulp (CTMP). The thermoforming conditions were varied between 2–100 MPa and 150–200 °C, while pressing sheets of 500 g/m² for 10 min to represent thin-walled packaging more closely. As our results showed, the temperature had a more pronounced effect on the CTMP substrates than on the Kraft pulp. This was explained by the greater abundance of lignin and hemicelluloses, while fibrillar dimensions and the fines content may play a role in addition. Moreover, the CTMP exhibited an optimum in terms of tensile strength at intermediate thermoforming pressure. This effect was attributed to two counteracting effects: 1) Improved fiber adhesion due to enhanced densification, and 2) embrittlement caused by the loss of extensibility. High temperatures likely softened the lignin, enabling fiber collapse and a tighter packing. For the Kraft substrates, the tensile strength increased linearly with density. Both pulps showed reduced wetting at elevated thermoforming temperature and pressure, which was attributed to hornification and densification effects. Here, the effect of temperature was again more pronounced for CTMP than for the Kraft fibers. It was concluded that the thermoforming temperature and pressure strongly affected the properties of the final material. The chemical composition of the pulps will distinctly affect their response to thermoforming, which could be useful for tailoring cellulose-based replacements for packaging products.

Поверхностная обработка картона суспензиями наноцеллюлозы растительного и бактериального происхождения

This study investigates powdered cellulose materials, particularly nanocellulose derived from plant and bacterial sources. The nanocellulose was generated by hydrolyzing bleached sulphate softwood and hardwood pulp samples with strong acids. The original materials are present in the product lines of leading Russian pulp and paper companies. The bacterial cellulose was produced under laboratory conditions from Medusomyces gisevii. The dimensional parameters of the nanocellulose samples were evaluated using electron microscopy, and the degree of polymerization was measured by determining the viscosity of the cellulose solutions in cadoxene. The bleached softwood pulp had a nanocellulose particle length of 80–200 nm, a particle diameter of 80–100 nm, and a degree of polymerization of 60. The bleached hardwood pulp had a particle length of 80–150 nm, a particle diameter of 70–100 nm, and a degree of polymerization of 50. The bacterial nanocellulose had a particle length of 120–250 nm, a particle diameter of 70–120 nm, and a degree of polymerization of 110. Suspensions of various concentrations (from 1 to 10 %) were prepared from nanocellulose samples, which were subsequently used as reinforcing additives in cardboard samples. The additive was applied to the surface in one or two layers. Additives of nanocellulose preparations reduced the breaking length (from 9.6 to 40.4 %) along with an increase in cardboard density (from 6.3 to 23.8 %), tensile rigidity (from 14.0 to 25.0 %) and bursting strength (up to 31.9 %). The best results were obtained by applying a nanocellulose suspension of bleached softwood pulp to the board surface in two layers: a 9.6 % decrease in breaking length was observed with an increase in density of 23.8 %, tensile rigidity of 25.0 %, and bursting resistance of 31.9 % relative to the control sample. Therefore, the study showed the possibility of using nanocellulose suspensions derived from plants and bacterial sources by acid hydrolysis for the surface treatment of cardboard. For citation: Toptunov Е.А., Sevastyanova Yu.V., Vashukova K.S. Surface Treatment of Cardboard with Plant and Bacterial Derived Nanocellulose Suspensions. Lesnoy Zhurnal = Russian Forestry Journal, 2023, no. 3, pp. 162–172. (In Russ.). https://doi.org/10.37482/0536-1036-2023-3-162-172

Financial instruments in the trade of forest products

The development of exchange trading in Russia is an urgent topic in connection with the modern transformation of the market for timber products under the influence of the pressure of sanctions restrictions on Russian producers, the restriction of supplies to Europe. Another important aspect of the relevance of the topic is related to ensuring transparency and reducing the shadow relations of participants in the market. The purpose of the study is to determine the current situation of stock trading and to identify the pricing patterns of spot and futures quotations for timber products. The paper highlights a number of issues of the current situation of exchange trading of timber products in Russia and world exchanges, highlights the specifics of exchange trading of timber products, and identifies the main factors determining the low liquidity of exchange trading. In 2021, the volume of timber trading on the Russian stock exchange amounted to 1% of the total volume of harvesting, which is the minimum trading volume, and therefore does not allow the formation of a relevant market price index. The paper considers the pricing of spot and futures quotations for timber products. The dynamics of bleached softwood pulp futures on the Shanghai Stock Exchange (SHFE), pulp and paper futures on the Norwegian Stock Exchange (NOREXECO) are analyzed. Modern measures and measures for the future up to 2025 aimed at activating exchange trading in LPC products, increasing the liquidity of the futures market for timber products are considered. The study shows the advantages of exchange trading, and possible prospects for the development of exchange trading of timber products in Russia.

The Impact of Fibre Oxidation on the Preparation of Cellulose Nanocrystals (CNC)

This study aimed to evaluate the effect of fibre oxidation on the extent of substituted sulfate on cellulose nanocrystals (CNC). In this investigation, fully bleached softwood (SW) and hardwood (HW) pulps from an Alberta pulp mill were oxidized under low (4%), medium (10%), and the higher-end of medium (14%) oxygen consistencies. The oxidized pulp samples were hydrolyzed with concentrated sulfuric acid under conventional procedures to produce CNC. The CNC materials were then characterized by different qualitative and quantitative techniques to evaluate the effect of oxidations on the number of substituted sulfates and the overall sulfate charge of isolated CNC to develop novel high-value applications. The experimental data show that fibre oxidation helped improve the overall CNC yield, with lower half-ester sulfate contents compared to the controls. The half-ester sulfate contents and the viscosity for SW CNC were found to be higher than their HW CNC counterparts. However, the thermal stability of CNC was found to be better for HW than SW pulps. The emerging data help to prepare and engineer CNC tailored to specific applications.

Piloting wet tensile strength development of polyamide-amine-epichlorohydrin wet strengthened nordic bleached softwood pulp paper by alkyl ketene dimer internal sizing

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

The effect of the strain rate on the longitudinal modulus of cellulosic fibres

The longitudinal stiffness of cellulosic fibres plays an important role in the mechanical performance of many products these fibres are used for. Especially, the fibres’ viscoelastic properties are having an influence on the product performance.In this work, tensile testing at different strain rates was performed on single fibres to investigate the rate dependence of their moduli. Four different fibre types were tested: chemi-thermomechanical softwood pulp (CTMP), bleached chemical softwood pulp (CP), unbleached softwood kraft pulp (UKP), and viscose (VIS). For each fibre sample, ten strain rates ranging from 0.113% s−1 to 800% s−1 were applied. The rate-dependent modulus E_{r} of each fibre at each strain rate was calculated by linearly fitting the stress–strain curves. By obtaining the values of the normalized modulus, a slope value per decade was calculated to quantify the rate dependence. To exclude possible plastic and relaxation effects, two additional experiments were used: a force-controlled loading–unloading experiment and a reverse rate protocol.All cellulosic fibres tested exhibited rate-dependent behaviour with a log-linear relationship between loading rate and modulus. For each tenfold increase in loading rate we found an increase in modulus up to nearly 20%—depending on the fibre type. Viscose fibres exhibit the highest rate dependence, whereas chemical softwood pulp fibres exhibit the lowest.

Wet tensile strength development of PAE wet-strengthened NBSK handsheets by AKD internal sizing

Polyamide-epichlorohydrin (PAE) is used in papermaking to increase the paper’s wet strength. High levels of PAE can make repulping of paper more difficult. PAE deposits can also impair paper machine performance by plugging the paper machine felts. The results of a preceding study indicated that the wet strength of paper containing a moderate amount of PAE (added amount 0.3 wt%) can be increased by utilizing internal alkylketene dimer (AKD) sizing. In the present study, the effects of an added amount of PAE and AKD on the wet strength of handsheets made from Nordic bleached softwood pulp (NBSK) were examined. The wet strength was measured after soaking the sheets in ion-exchanged water for up to 1 month. The improving effect of AKD sizing on the wet strength was long-lasting and it was apparent especially with a low and moderate added amount of PAE (0.15 and 0.45 wt%) resulting in higher wet strength than the highest added amount of PAE (1.35 wt%) alone. No clear sign of worsened repulpability was observed at low to moderate treatment levels. The results suggest that use of small or moderate amounts of PAE with AKD can be a viable option for paper mills facing problems related to the high usage of PAE.

Influence of temperature and fiber content on direct shear properties of plain ice and fiber-reinforced ice

As a new kind of building material, ice has been paid more and more attention and applied in cold, polar regions and the outer space. The shear mechanical properties of plain ice and fiber-reinforced ice (FRI) were studied by a modified direct shear test. Five types of FRI containing 0%, 1%, 2%, 4% and 6% fiber content of bleached sulfate softwood pulp (BSSP) fiber were prepared and tested under −20, −15, −10 and − 5 °C. The results showed that the brittle failure of plain ice was in contrast to the ductility of FRI. With the decrease of temperature, the shear strength and peak deformation increased. The shear strength and deformation of ice at −20 °C were 2–2.5 times and 1.1–1.4 times higher than those at −5 °C. The study also showed that with the increasing fiber content, the shear strength and peak deformation increased. The shear strength and peak deformation of FRI with 6% fiber content were 3.8–5.9 times and 2–3times higher than those of plain ice. Equations predicting the shear strength and peak deformation of ice considering the temperature and fiber content were proposed, and the relationship between shear strength and compressive strength was investigated. Through the analysis of shear ductility coefficient, the increase of fiber content and decrease of temperature greatly improved the energy absorption capacity and subsequent bearing capacity of ice in the shear process. A shear constitutive model was proposed to predict the relationship between shear strength and deformation.

Production and Characterization of Cellulose Nanofiber Slurries and Sheets for Biomedical Applications

Cellulose nanomaterials are produced employing a multitude of methodologies including electrospinning, bacterial generation, acid digestion, and a variety of mechanical defibrillation techniques; the morphology of the nanomaterial produced is specific to the production process. Feedstocks range from various forms of woody biomass, to fungi, and have a great impact on the resulting product. The mechanical defibrillation technique, such as that employed in the present work, continuously breaks down cellulose fibers suspended in water via segmentation and defibrillation through grinding and refining. The process is typically operated until a desired level of fines is achieved in the resultant slurry of cellulose nanofiber (CNF), alternatively known as cellulose nanofibril. Mechanical defibrillation processes can be built to produce several liters in a small batch system or up to tons per day in a continuous pilot scale refiner system. In the present work a continuous system was developed with the capacity to produce 14 L of cellulose nanofiber slurry with consistent specifications and in a manner compliant with GMP/GLP protocols in order to be amenable to biomedical applications. The system was constructed within an ISO class 7 cleanroom and refining was performed on bleached softwood pulp suspension in purified water. This manuscript details the continuous grinding system, the processes employed to produce cellulose nanofiber, and characterizes the resultant cellulose nanofiber slurry and sheets formed from the slurry.

EFFECT OF CHITOSAN ADDITION DURING PAPER-MAKING ON AGEING STABILITY OF DOCUMENT PAPER

The aim of the present work has been to study the influence of chitosan addition into the composition of paper intended for documents on its ageing stability, with a view of enhancing the resistance of paper strength and optical properties over time. The chitosan solution was added during the formation of the paper sheets in various amounts: 0.2%, 1% and 2% o.d.f. Paper samples of different fibrous compositions were prepared from bleached sulphate softwood pulp (BSWP) and bleached sulphate hardwood pulp (BHWP) in the following ratios: 50% BSWP:50% BHWP, 80% BSWP:20% BHWP, 100% BSWP and 100% BHWP. Then, paper samples were subjected to accelerated thermal ageing for 24 hours at 105 °C. It was found that the use of chitosan as additive in the composition of bleached cellulose paper samples led to improved strength and hygroscopic properties. The study showed that chitosan could be used in the production of kraft document papers comprising aluminium sulphate, as the presence of aluminium sulphate had no negative effect on the action of the biopolymer. Regarding the complex evaluation of the properties of the obtained papers, it could be summarized that, for the studied fibrous compositions, the optimum amount of the additive was 1% chitosan for a fibrous composition of 50% bleached softwood pulp and 50% bleached hardwood cellulose. Therefore, preparing document paper with the addition of chitosan is a convenient procedure to enhance a number of paper properties, even after the ageing process.

The paper-forming properties of hemp fire peroxide cellulose in combination with wood sulphate cellulose

Hemp fire (Cannabis sativa) was delignified with the reaction mix “acetic acid - hydrogen peroxide - sulfuric acid catalyst - water” under sulfuric acid concentration of 0.45%, liquid module of 6, and temperature of 85 ° C. The cellulose was ground to 34 … 36°SHR and mixed in different ratios in compliance with the simplex-centroid experimental design with bleached sulfate softwood and hardwood pulp. The influence of the mixed composition formulations on the main strength properties of paper castings has been studied. It has been concluded that technical cellulose obtained from hemp fire applying this method, can be used for paper products manufacturing in combination with sulphate cellulose from coniferous and deciduous wood.

Регулирование деформационных свойств бумаги путем варьирования степени ее анизотропии

Mechanical properties are crucial in assessing the paper quality. Deformation and strength properties of paper are determined by the strength and stiffness of the interfiber and intermolecular hydrogen bonds. The contribution ratio of interfiber and intermolecular hydrogen bonds to the strength of paper can be changed by adjusting the degree of its anisotropy. The article presents the results on a study of the deformation properties of laboratory anisotropic paper samples from kraft bleached softwood pulp with a beating degree of 30 °SR. The samples had basic weight of 90 g/m2 and the degree of stiffness anisotropy TSIMD/CD of 1.75–4.08. They were made by using Techpap SAS automatic dynamic handsheet former (Grenoble, France), with varying forming parameters – diameter of the nozzle, motion speed of the forming wire, and injecting speed of pulp. Deformation properties were determined by tensile test and processing of the stress-strain dependence (σ−ε). The outcomes have shown that, an increase of the fiber orientation degree in paper structure by changing the forming parameters caused a change in the nature of the paper deformation under tension. Increasing the fiber orientation degree in the structure of paper made it possible to increase the strength by 55 %, tensile stiffness by 63 % in the machine direction, while reducing the extensibility by 10 %. In the cross direction, it was possible to decrease tensile stiffness by 33 %, strength by 55 %, and increase the extensibility by 5 %. Anisotropy of tensile strength was 1.73–6.00. The greatest effect was obtained for the elasticity modulus in the pre-failure zone E2 (2.8–38.6). It means that, fiber orientation had a key importance when large deformations in the samples took place. The established quantitative regularities allowed optimizing the values of the deformation and strength properties of paper, and their ratio in the machine direction and cross direction due to the variation of the forming parameters. For citation: Rech D., Potasheva A.N., Kazakov Ya.V. Regulating the Deformation Properties of Paper by Varying the Degree of Its Anisotropy. Lesnoy Zhurnal [Russian Forestry Journal], 2021, no. 5, pp. 174–184. DOI: 10.37482/0536-1036-2021-5-174-184

Effects of hydrophobic sizing on paper dry and wet-strength properties: A comparative study between AKD sizing of NBSK handsheets and rosin sizing of CTMP handsheets

Alkyl ketene dimer (AKD) and rosin sizing are used in papermaking to decrease paper’s tendency to absorb liquid water. Earlier information regarding the effects of internal sizing on paper dry strength is not consistent. In the present laboratory study, AKD sizing of handsheets made from Nordic bleached softwood pulp (NBSK), and rosin sizing of handsheets made from Nordic hardwood chemi-thermomechanical pulp (CTMP) were done via an internal sizing method, and by immersing handsheets in aqueous sizing agent dispersion. In the study, AKD sizing had no significant effect on the dry strength of NBSK handsheets. The result corresponds to practical experiences of papermakers. However, both AKD sizing methods resulted in a substantial and long-lasting increase of handsheet wet-strength. Unlike internal AKD sizing of NBSK handsheets, rosin internal sizing of CTMP handsheets resulted in decreased handsheet dry strength. The decrease indicates that, under the conditions present during the experiment, rosin sizing agents interfered with interfiber hydrogen bonding of CTMP fibers. Given that, in practice, no such undesired effects have been commonly linked to rosin sizing, the observed effect may be specific to sheet-making conditions. However, the effect of rosin sizing on strength properties and their variation cannot be ruled out completely.

News Print from Corn Stalk Fiber: Industrial and commercial Trials

Abstract The chemical composition of corn stalk as well as fiber morphology, fiber length and diameter were carried out. Furthermore, Kraft pulping process using different cooking conditions (temperature, 125 – 170oC, time, 15 - 40 min., and % alkali 9 - 12%) were done at laboratory scale. The obtained pulps were characterized with respect to %yield, %rejects, kappa number and rest alkali. Effect of chemical composition of corn stalk on yield and kappa number was discussed. The mechanical properties of hand sheet paper were explained in details, according to different cooking conditions. The high ash content and the relatively short fiber of corn stalk can attribute to positive effect with respect to bulk, opacity and the necessary strength of paper which are important properties in newspaper. Industrial trials were carried out using Pandia continuous digester(74 tons corn stalk kraft pulp was produced) and 90 tons newsprint paper (furnish: 86.5% bleached corn stalk pulp + 13.5 bleached soft wood pulp) was obtained using Furdirinier paper machine. The produced newsprint was printed and commercialized by four famous newsprint companies in Cairo – Egypt (about twenty tons for each). Comparison with the imported newsprint paper was done, the produced newsprint has better qualities with respect to opacity, and strength properties. Findings from industrial and commercialized trials in this study provide insights into new opportunities to utilize corn stalk pulp as better alternative to produce good quality of newsprint.

Surface Characterization of Powdered Cellulose Activated by Potassium Hydroxide in Dry Condition Through Ball Milling

The surface chemical compositions of powdered cellulose have been characterized utilizing X-ray photoelectron spectroscopy (XPS) and attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR) techniques. Powdered cellulose was prepared by milling of bleached softwood pulp residues through a lab-scale planetary ball mill. Here we show how milling a mixture of the powdered cellulose with potassium hydroxide determines the surface chemical compositions of the obtained powdered cellulose, in a completely dry condition. The XPS analysis indicated the presence of new carbon and oxygen atoms as C4, C5, and O3. In turn, the FTIR analysis showed the stretching vibrations of the carbon–carbon double bond. The results suggest the formation of active oxygenated species on powdered cellulose surfaces.