PAPER making! FROM THE PUBLISHERS OF PAPER TECHNOLOGY INTERNATIONAL ® FROM THE PUBLISHERS OF PAPER TE Volume 8, Number 3, 2022
Assessment of the Performance of Cationic Cellulose Derivatives as Calcium Carbonate Flocculant for Papermaking JORGE F. S. PEDROSA 1 , LUÍS ALVES 1 , CARLOS P. NETO 2 , MARIA G. RASTEIRO 1 & PAULO J. T. FERREIRA 1 . Cationic polyacrylamides (CPAMs) are usually used as filler retention agents in papermaking formulations. However, increasing environmental restrictions and their non-renewable origin have driven research into bio- based alternatives. In this context, cationic lignocellulosic derivatives have been attracting considerable research interest as a potential substitute. In this work, distinct cationic celluloses with degrees of substitution of between 0.02 and 1.06 and with distinct morphological properties were synthesized via the cationization of bleached eucalyptus kraft pulp, using a direct cationization with (3-chloro-2-hydroxypropyl) trimethylammonium chloride (CHPTAC) or a two-step cationization, where the cellulose was first oxidized to form dialdehyde cellulose and was then made to react with Girard’s reagent T (GT). Fibrillated samples were produced by subjecting some samples to a high-pressure homogenization treatment. The obtained samples were evaluated regarding their potential to flocculate and retain precipitated calcium carbonate (PCC), and their performance was compared to that of a commercial CPAM. The cationic fibrillated celluloses, with a degree of substitution of ca. 0.13–0.16, exhibited the highest flocculation performance of all the cationic celluloses and were able to increase the filler retention from 43% (with no retention agent) to ca. 61–62% (with the addition of 20 mg/g of PCC). Although it was not possible to achieve the performance of CPAM (filler retention of 73% with an addition of 1 mg/g of PCC), the results demonstrated the potential of cationic cellulose derivatives for use as bio-based retention agents. Contact information: 1 University of Coimbra, CIEPQPF, Department of Chemical Engineering, Pólo II, R. Sílvio Lima, 3030-790 Coimbra, Portugal 2 Forest and Paper Research Institute (RAIZ), R. José Estevão, Eixo, 3800-783 Aveiro, Portugal Polymers 2022, 14, 3309.
https://doi.org/10.3390/polym14163309 Creative Commons Attribution 4.0 License
The Paper Industry Technical Association (PITA) is an independent organisation which operates for the general benefit of its members – both individual and corporate – dedicated to promoting and improving the technical and scientific knowledge of those working in the UK pulp and paper industry. Formed in 1960, it serves the Industry, both manufacturers and suppliers, by providing a forum for members to meet and network; it organises visits, conferences and training seminars that cover all aspects of papermaking science. It also publishes the prestigious journal Paper Technology International ® and the PITA Annual Review , both sent free to members, and a range of other technical publications which include conference proceedings and the acclaimed Essential Guide to Aqueous Coating .
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Article 1 – Papermaking Flocculants
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