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Journal articles
Magazine articles
A novel predictive method for filler coflocculation with cellulose microfibrils, TAPPI Journal November 2019
ABSTRACT: Different strategies aimed at reducing the negative impact of fillers on paper strength have been the objective of many studies during the past few decades. Some new strategies have even been patented or commercialized, yet a complete study on the behavior of the filler flocs and their effect on retention, drainage, and formation has not been found in literature. This type of research on fillers is often limited by difficulties in simulating high levels of shear at laboratory scale similar to those at mill scale. To address this challenge, a combination of techniques was used to compare preflocculation (i.e., filler is flocculated before addition to the pulp) with coflocculation strategies (i.e., filler is mixed with a binder and flocculated before addition to the pulp). The effect on filler and fiber flocs size was studied in a pilot flow loop using focal beam reflectance measurement (FBRM) and image analysis. Flocs obtained with cationic polyacrylamide (CPAM) and benonite were shown to have similar shear resistance with both strategies, whereas cationic starch (CS) was clearly more advantageous when coflocculation strategy was used. The effect of flocculation strategy on drainage rate, STFI formation, ash retention, and standard strength properties was measured. Coflocculation of filler with CPAM plus bentonite or CS showed promising results and produced sheets with high strength but had a negative impact on wire dewatering, opening a door for further optimization.
Journal articles
Magazine articles
Lignin-based resins for kraft paper applications, TAPPI Journal November 2019
ABSTRACT: We investigated miscanthus (MS) and willow (W) lignin-furfural based resins as potential reinforce-ment agents on softwood and hardwood kraft paper. These resins might be sustainable alternatives to the commercial phenolformaldehyde (PF) resins. Phenol is a petrochemical product and formaldehyde has been classified as a carcinogen by the U.S. Environmental Protection Agency. The lignin used in this study was derived from hot water extraction (160ºC, 2 h) of MS and W biomass, and may be considered sulfur-free. These biorefinery lignins were characterized for their chemical composition and inherent properties via wet chemistry and instrumental techniques. The resin blends (MS-resin and W-resin) were characterized for their molecular weight, thermal behavior, and mechanical properties. Mechanical properties were measured by the resin’s ability to reinforce softwood and hard-wood kraft papers. The effect of adding hexamethylenetetramine (HMTA), a curing agent, to the resin was also examined. Mixtures of PF and lignin-based resins were investigated to further explore ways to reduce use of non-renewables, phenol, and carcinogenic formaldehyde. The results show that lignin-based resins have the potential to replace PF resins in kraft paper applications. For softwood paper, the highest strength was achieved using W-resin, without HMTA (2.5 times greater than PF with HMTA). For hardwood paper, MS-resin with HMTA gave the highest strength (2.3 times higher than PF with HMTA). The lignin-based resins, without HMTA, also yielded mechanical properties comparable to PF with HMTA.
Conference papers
Biodegradable Paper-based Coffee Cups: Current Progress and Outlook, 19Papercon
Biodegradable Paper-based Coffee Cups: Current Progress and Outlook, 19Papercon
Conference papers
Surface application of cellulose microfibrils on paper • Effects of basis weight and surface coverage levels, 19PaperCon
Surface application of cellulose microfibrils on paper • Effects of basis weight and surface coverage levels, 19PaperCon
Conference papers
Moisture management and optimization from headbox to reel in papermaking process, 19PaperCon
Moisture management and optimization from headbox to reel in papermaking process, 19PaperCon
Conference papers
Water & Air Ingress Into Paper Machine Circulating Oil, 19PaperCon
Water & Air Ingress Into Paper Machine Circulating Oil, 19PaperCon
Conference papers
Polyolefin Based Waterborne Barrier Coatings for Paperboard, 19PaperCon
Polyolefin Based Waterborne Barrier Coatings for Paperboard, 19PaperCon
Conference papers
Development of additive transfer and dosing system with straight forward steps improves cleanliness, quality and runnability, 19PaperCon
Development of additive transfer and dosing system with straight forward steps improves cleanliness, quality and runnability, 19PaperCon
Conference papers
Strength Development During Drying Possibilities with A Different Wet Strength Testing Approach, 19PaperCon
Strength Development During Drying Possibilities with A Different Wet Strength Testing Approach, 19PaperCon
Conference papers
Micro Characterization of z-resistance of papers, 19PaperCon
Micro Characterization of z-resistance of papers, 19PaperCon