PAPERmaking! FROM THE PUBLISHERS OF PAPER TECHNOLOGY Volume 6, Number 2, 2019
feature for a majority of paper products, such as packaging materials or novel construction materials, since the ingress of moisture is a major cause of paper damage. Cellulose micro and nanofibrils as coating agent for improved printability in office papers, Ana F. Lourenço, José A.F. Gamelas, Pedro Sarmento & Paulo J.T. Ferreira, Cellulose , 27, 2020, https://doi.org/10.1007/s10570-020-03184-9. The use of nanocelluloses is being conducted for the most diverse applications. Their performance as coating agent has been mainly explored to improve barrier properties, as they emerge as perfect candidate for plastic substitution, but it is also important to explore their potential to improve printing quality. In the present work, the influence of different nanocelluloses, obtained through mechanical, enzymatic, TEMPO-mediated oxidation and carboxymethylation treatments, in the coating process and inkjet printability of office papers was assessed. The results revealed that the cellulose nanofibrils are better for printability than the microfibrils. But the size and charge of the former must be taken into account, since fibrils of very small size penetrate the paper structure, dragging the pigments from the surface, and very anionic nanofibrils can also have negative influence on the optical density. Besides, an interesting synergy between surface-sizing starch and the cellulose nanofibrils was found to occur as the latter closed the paper structure, which prevented starch from penetrating, while potentiating both of their positive effects on ink pigment entrapment. An additional study of characterization of inkjet pigments was also performed. Surface modification of clay Ǧ coated paper by atmospheric Ǧ pressure plasma in air, Vlasta Štěpánová, Dušan Kováčik, Miroslav Zemánek, Monika Stupavská, Zlata Kelar Tučeková & Mirko Černák, Surface and Interface Analysis , 42(12), Dec. 2020, https://doi.org/10.1002/sia.6798. The aim of this work was the wettability improvement of clay Ǧ coated paper by ambient air plasma exposure. Industrial corona with a volume dielectric barrier discharge in cylindrical configuration was used as a plasma source; the exposure times varied from 0.25 up to 5 s. Water contact angle (WCA) measurement and surface free energy (SFE) evaluation were carried out for the estimation of wettability changes. Plasma treatment in the duration of 0.25 s was sufficient to decrease the WCA almost to the half of the original value, which was 76°. SFE of paper has increased by 40% – 50% after plasma treatment. Long Ǧ term ageing effect study of treated samples was carried out up to 3 months after the treatment. WCA did not reach the original value even after 3 months, and it was still 20% – 30% lower. O/C ratio increased from 0.7 to 1.8 in case of 5 Ǧ s plasma treatment, and the new chemical bonds (C=O, O – C=O) were created on the surface. ENVIRONMENT The future of single-use paper coffee cups: Current progress and outlook, N. Triantafillopoulos & A.A. Koukoulas, BioResources , 15(3), DOI: 10.15376/biores.15.3.Triantafillopoulos. The expanded use of environmentally friendly and sustainable foodservice packaging continues to be a prime focus of stakeholders across the foodservice value chain. Paper-based coffee cups is one product segment where effective recycling of waste cups remains elusive. As a result, material substitutes for polyethylene liners are emerging to solve the problem of waste cups. In this paper, current and emerging commercial material technologies used in the production of paper- based coffee cups that are readily recyclable with other paper grades are reviewed. Many of these material solutions are also compostable. Special attention is paid to the rapidly evolving, alternative large-scale production of bioplastics. Multiple efforts to effectively develop a more environmentally friendly paper cup are also examined. It is clear that
Technical Abstracts
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