Search
Use the search bar or filters below to find any TAPPI product or publication.
Filters
Content Type
Publications
Level of Knowledge
Committees
Collections
Journal articles
Editorial: Investing in Amercian advanced manufacturing, TAPPI Journal June 2025
ABSTRACT: American manufacturing is seeing a renewal, which is needed to boost jobs in America, particularly in the middle and manufacturing base of the country. The ongoing tariff situation emphasizes the importance of protecting domestic manufacturing. There is U.S. congressional agreement, in principle, to bring back manufacturing to the United States. However, given how the global trade and manufacturing space has shifted in the last four decades, it may not be a comparative advantage to manufacture low margin and labor-intensive products. Officials in the current U.S. Administration have stated that manufacturing of socks and T-shirts is not necessarily in the interest of the United States, but focusing on value-added products is essential. While silicon chips, solar panels, and batteries are key items of interest, advanced textile materials such as those that find applications in industrial products and composites, products that can save human lives, and products for protecting the environment are highly-valued items that cater to national security.
Journal articles
Conversion of paper-grade pulp from rice straw into dissolving pulp, TAPPI Journal June 2025
ABSTRACT: About 1,165 million metric tons of rice straw is generated every year worldwide, which can be a good source for the circular bioeconomy. In this research paper, the paper-grade pulp from rice straw was converted to dissolving-grade pulp by fractionation in a biorefinery initiative. Rice straw was cooked at an optimum condition of 8% potassium hydroxide (KOH) charge for 120 min at 150°C and produced a pulp yield of 47.2% with a kappa number of 18.5. Subsequently, D0(EP)D1 bleaching was carried out for the produced pulp, and the brightness of the pulp reached to 82.4%. From the black liquor, 16.5% of the lignin and 11.9% of the hemicellulose were isolated for producing biobased products and chemicals, and then the spent liquor was used for soil amendment. The bleached pulp was fractionated in a Bauer McNett fiber classifier. The pulp fibers retained on 16-, 30-, and 50-mesh screens were used as a longer fiber fraction pulp, and pulp fibers retained on 100- and 200-mesh screens were used as a shorter fiber pulp. The longer and shorter fiber fraction pulps were analyzed for cellulose, R10, pentosan, and viscosity. The long fiber fraction pulps were characterized by higher cellulose (88.2% vs. 83.1%) and lower pentosan (11.3% vs. 13.0%) content than the shorter fiber fraction pulps. The longer fiber fraction was further treated with cold KOH to remove residual hemicellulose. The KOH extraction reduced pentosan content in pulp to 6.3% and increased á-cellulose content to 91.3%. The short fiber fraction was converted to monomeric sugars using cellulase enzymes with varying reaction time, temperature, and consistency. The efficiency of cellulase activity was assessed through glucose yield and residual dry weight. A temperature of 45°C, 5.0 pH, 5% consistency, and 6 filter paper units/gram (FPU/g) o.d. pulp resulted in maximum sugar conversion of 85.7%.
Journal articles
The effect of Stachys floridana Shuttlew.ex Benth extract as an additive on the chemical properties of chitosan biodegradable film, TAPPI Journal June 2025
ABSTRACT: The purpose of this study is to explore chitosan with Stachys floridana Shuttlew. ex Benth (SFSB) extract as an additive to prepare an active film. The effects of the SFSB extract on the physical, antioxidant, and bacteriostatic properties of chitosan biodegradable films were studied. The results showed that the addition of SFSB extract significantly improved the antioxidant and antibacterial properties of the film, and its biodegradation rate increased rapidly. Compared to the control film, the water solubility was lower at 19.40%, the expansion degree was higher at 288.90%, the water vapor permeability (WVP) was 0.364 g·mm/(m²·d·kPa), the surface hydrophobicity increased, and the mechanical strength was also improved. The contact angle increased to 89.3°. In addition, as the amount of SFSB increased, the thermal stability of chitosan-Stachys floridana Shuttlew. ex Benth (CS-SFSB) films also increased significantly, and their ultraviolet (UV) blocking ability was gradually enhanced. The results indicate that CS-SFSB has potential as a food packaging material.
Journal articles
Gap mechanics in pulp refiners, TAPPI Journal June 2025
ABSTRACT: Studies of pulp refining have shown that a single bar impact on pulp has only a 1%•5% probability of producing a successful refining effect. This study has explored the reason why. An analysis of refining kinetics suggested that small segments of a fiber length, about a fiber diameter in size, are treated during each impact. Measurements of localized swelling along fiber lengths caused by refining supported this finding. Based on these findings, it was postulated that force transmittal through fiber networks occurred primarily at fiber crossings. The small size of fiber diameters relative to fiber lengths accounts for the low probability of a successful refining event at each impact. This probability, and the probability of fibers being captured and impacted during passage through a refiner, account for the need for multiple bar crossings to refine pulps.
Journal articles
Editorial: Meeting highlights challenges and opportunities with lignin valorization and biobased products, TAPPI Journal May 2025
ABSTRACT: Earlier this year, around 30 participants gathered for a virtual meeting to discuss the challenges and potential opportunities existing in the lignin research community. Moderated by Jan Bottiglieri, editor of TAPPI’s Paper360° Magazine, the meeting included experts from industry, academia, research organizations, and manufacturing consortia. Below are some of the key points of discussion, central among which was the need for more collaboration within the lignin research community.
Journal articles
Colloidal silica and its effects during formation of paper sheets in the presence of nanofibrillated cellulose, cationic starch, and cationic acrylamide copolymer, TAPPI Journal May 2025
ABSTRACT: This work considered effects of colloidal silica addition during laboratory preparation of paper sheets containing nanofibrillated cellulose (NFC) that had been pretreated with cationic starch. The emphasis was on process performance issues, including dewatering rates, fine particle retention, and the extent of fiber flocculation. In addition, micrographs were obtained to show what was happening to the NFC upon treatments with cationic starch and subsequent application of hydrodynamic shear. Contrasting results were obtained, depending on the charge density of the cationic starch. Pretreatment of the NFC with a high charge density cationic starch (degree of substitution 0.2) resulted in strong interactions with the colloidal silica, enhancing the dewatering rate and contributing to fine-particle retention. The medium charge cationic starch pretreatment led to effects suggesting a bridging mechanism of action, and subsequent colloidal silica had no significant effect on dewatering. Treatment of that system with a high level of colloidal silica (0.2%) resulted in lower retention. In general, the final colloidal silica treatments tended to decrease the level of flocculation in the suspensions, giving more uniform handsheets. Mechanisms, some of them related to the clustering and dispersion of cationic starch-treated NFC, were proposed to account for the observed effects.
Journal articles
Paper strength factors in systems with nanofibrillated cellulose, cationic starch, colloidal silica, cationic acrylamide copolymer, and hydrodynamic shear, TAPPI Journal May 2025
ABSTRACT: Laboratory paper sheets were formed by first pretreating nanofibrillated cellulose (NFC) with cationic starch at the 5% level by mass. The treated NFC was then added to stock prepared from 100% recycled copy paper. The combined furnish was next optionally treated with a cationic retention aid (cPAM, 0.1%) and then colloidal silica (0.1% or 0.2%). Vacuum dewatering, fine-particle retention, and several paper properties were studied as a function of the colloidal silica level (zero, 1%, and 2%) and at different levels of shear stress applied just before forming the sheets. Dewatering and strength results were generally more favorable when using a medium charge cationic starch (~ 0.03 degree of substitution, DS) to pretreat the NFC rather than a high charge density cationic starch (~ 0.2 DS). In each case, the dewatering was further enhanced by subsequent treatments by cPAM (0.1% on whole furnish solids) and then even more with the final addition of colloidal silica (0.1% and 0.2% levels compared). However, the colloidal silica additions progressively hurt the tensile strength of the paper, especially in the case of the high charge cationic starch and at the higher level of colloidal silica. Though the dewatering performance was favorable, in such cases, the paper strength was not improved compared to paper made without any NFC. The fact that the systems involving cPAM treatment, and especially those involving both cPAM and colloidal silica, tended to reduce the resulting paper’s tensile strength supports a mechanism in which the additives result in the clustering of the NFC, possibly in multiparticle bunches. Evidence suggests that such bunches of clustered NFC particles, which are difficult to redisperse even at levels of hydrodynamic shear present in high-speed paper machine systems, are resistant to full integration into the sheet structure as the paper is being formed.
Journal articles
Research on an energy model for X-ray measurement of paper ash content using COMSOL, TAPPI Journal May 2025
ABSTRACT: Ash content is one of the critical quality parameters in papermaking production. Traditional 55Fe radioactive sources used for online ash content measurement have a short lifespan and high costs, while offline methods such as the combustion method or chemical analysis are time-consuming. Using an X-ray tube as the radiation source, continuous X-ray measurement offers advantages such as being rapid, non-destructive, and cost-effective. In this study, COMSOL software was employed to simulate the measurement process and establish an energy attenuation model for X-ray measurement of paper ash content. The model simulates the energy attenuation of X-rays before and after transmission through four materials: calcium carbonate (CaCO3), titanium dioxide (TiO2), wood-based plant fibers, and paper samples filled with CaCO3. The absorption coefficients of paper samples with varying ash content were investigated using the model and compared with experimental results obtained from continuous X-ray measurements. The results indicate that the proposed energy simulation model can reduce the measurement error of paper ash content by 1%, significantly enhancing the reliability and accuracy of ash content measurement.
Journal articles
Magazine articles
Editorial: TAPPI Journal 2024 Best Research Paper focuses on realistic potential for using nonwood residues in sustainable packaging, TAPPI Journal April 2025
ABSTRACT: Each year, the TAPPI Journal Editorial Board honors outstanding content by nominating and voting for the Best Research Paper published the previous year based on scientific merit, innovation, creativity, and clarity. TAPPI and the TAPPI Journal Editorial Board would like to congratulate the authors of the 2024 TAPPI Journal Best Research Paper: Antonio Suarez, Ashok Ghosh, Fritz Paulsen, and Peter W. Hart of Smurfit Westrock (formerly WestRock). The winning paper, “Life cycle carbon analysis of packaging products containing nonwood residues: A case study on linerboard and corrugating medium,” was published in the March 2024 issue.
Journal articles
Magazine articles
Numerical analysis of the impact of rotor and screen hole plate design on the performance of a vertical pulper, TAPPI Journal April 2025
ABSTRACT: The dissolving of mechanical pulp is one of the most important process steps in stock preparation, since pulping occurs at the very beginning of the papermaking process. Efficient mixing of the pulp in a short amount of time is essential to achieve high furnish volume flow rates. The design of the rotor, as well as the pulper vat and inserts, significantly affects the overall performance of the pulper, such as mixing efficiency and power demand. Using advanced numerical methods such as computational fluid dynamics (CFD) can accelerate the development process. The CFD simulations allow for detailed analysis of flow phenomena, making it possible to study a real-size machine numerically. This approach is particularly advantageous because it can reduce the need for timeconsuming and costly experiments associated with scaling up test rigs. In this study, we compared two different rotor designs utilized in a vertical pulper and evaluated the numerical results with experimental data. Rotor A is designed for low turbulence and low power demand, while rotor B is designed for high turbulence with high power demand. The CFD results showed good agreement with the experimental measurements. We investigated how the rotor design influences the free fluid surface and the mixing efficiency. Our study also highlights the differences in results depending on whether water or furnish is simulated, which exhibit Newtonian or, respectively, non-Newtonian fluid behavior. Additionally, a detailed numerical investigation of various screen hole plate designs revealed that the newly developed hole design significantly reduces pressure loss compared to a standard drilled hole. This outcome was consistent for both types of fluids investigated: water and furnish.