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SetPoint: Tissue Packaging is Changing, Tissue360º Spring/Summer 2020

SetPoint: Tissue Packaging is Changing, Tissue360º Spring/Summer 2020

How to Reduce CO2 Emissions from Tissue Machines, Tissue360º Spring/Summer 2020

How to Reduce CO2 Emissions from Tissue Machines, Tissue360º Spring/Summer 2020

SetPoint: Meet Dave Automation and AI are Key to the Future, Tissue360º Fall/Winter 2023

In case you missed it in TAPPI’s electronic newsletter, Tissue360º Fall/Winter 2023

Earn the Competitive Advantage with Warm-up Contactless, Tissue360º Fall/Winter 2023

How to Optimize Waste Management in the Tissue Converting Process, Tissue360º Fall/Winter 2023

Pulp for Tissue: Södra’s 80-year Investment Plan, Tissue360º Fall/Winter 2023

Pulp for Tissue: Södra’s 80-year Investment Plan, Tissue360º

Achieve Superior Performance with TT Headbox, Tissue360º Fall/Winter 2023

Achieve Superior Performance with TT Headbox, Tissue360º Fal

Mechanistic aspects of nanocellulose•cationic starch•colloidal silica systems for papermaking, TAPPI Journal February 2023

ABSTRACT: Optimization of a chemical additive program for a paper machine can require attention to both colloidal charges and kinetic effects. This work considered an additive program with two negatively charged substances (nanofibrillated cellulose [NFC] and colloidal silica) and two positively charged items (cationic starch and cationic acrylamide copolymer retention aid). Results were shown to depend on charge interactions; however, that clearly was not the whole story. Some findings related to cationic demand, dewatering, fine-particle retention, and flocculation among fibers were best explained in terms of at least partly irreversible complexation interactions between the charged entities. Adjustments in ratios between oppositely charged additives, their sequences of addition, and effects of hydrodynamic shear levels all affected the results. In general, the most promising results were obtained at a cationic starch level of 0.25% to 0.5% based on sheet solids in systems where the cationic starch was used as a pretreatment for NFC.

Setting priorities in CNF particle size measurement: What is needed vs. what is feasible, TAPPI Journal February 2023

ABSTRACT: Measuring the size of cellulose nanomaterials can be challenging, especially in the case of branched and entangled cellulose nanofibrils (CNFs). The International Organization for Standardization, Technical Committee 6, Task Group 1—Cellulosic Nanomaterials, is exploring opportunities to develop standard methods for the measurement of CNF particle size and particle size distribution. This paper presents a summary of the available measuring techniques, responses from a survey on the measurement needs of CNF companies and researchers, and outcomes from an international workshop on cellulose nanofibril measurement and standardization. Standardization needs differed among groups, with Japanese companies mostly requiring measurements for product specification and production control, and other companies mostly needing measurements for safety/regulatory purposes and for grade definitions in patents. Among all the companies, average length and width with percen-tiles (D(10), D(50), D(90)) were the most desired measurands. Workshop participants concurred that defining the location(s) on the CNF at which to measure the width and the length is an urgent and complex question. They also agreed that methods are needed for rapid particle size measurement at the nanoscale. Our recommendation within ISO is to start work to revise the definition of CNFs and develop sample preparation and measurement guidelines. It was also recommended that further research be done to reproducibly prepare hierarchical branched CNF structures and characterize them, develop automated image analysis for hierarchical branched CNF structures, and develop a classification system encompassing measurements at multiple size ranges from micro- to nanoscale to fully characterize and distinguish CNF samples.