PAPER making! FROM THE PUBLISHERS OF PAPER TECHNOLOGY INTERNATIONAL ® Volume 10, Number 2, 2024
periods of time (> ∼ 1 h) when the caps were directly exposed to liquid. However, the liquid barrier was satisfactory when the products were exposed to increased relative humidity in refrigerated conditions (relative humidity >76% and temperature <7 °C). “Investigation of a lignocellulose fiber hornification treatment for improving the functionality of apple pomace- based pulp for molded pulp packaging”, Emma Gordy, Jooyeoun Jung & Yanyun Zhao, International Journal of Biological Macromolecules , Vol.263(Pt.1), April 2024, 130265. Transfer molded pulp packaging (TMPP) is a viable alternative to single use plastic packaging. TMPP is typically produced from recycled newspapers, but the availability of this feedstock material is declining. Apple pomace (AP) pulp, primarily composed of cellulose, hemicellulose, lignin, and pectin, can be used as the primary component of TMPP, but its high water retention value (WRV) and separation from other pulps (recycled cardboard (CB) in this study) limits its utilizations in TMPP. A pressing and thermal drying cellulose hornification treatment followed by a repulping step was implemented to reduce pulp WRV and enhance AP and CB fiber entanglements. 11%, 20%, and 25% reductions in WRV were achieved through 1 t-force pressing and drying at 120°C for 2.5, 15, or 27.5min, named mild, medium, and strong hornification treatments, respectively. Increased AP and CB fiber entanglements were observed via microscopy with rising hornification drying times. The medium hornification treatment was identified as the optimal treatment for reducing pulp WRV and reducing pulp separation without decreasing pulp sheet tensile strength. This study introduced and validated a novel processing technique for improved functionality of AP-based pulp for packaging applications. NANO-SCIENCE “The effect of pre -treatment and process conditions on the gas barrier properties of fibrillated cellulose films and coatings: A review”, Robyn Hill, Jon Phipps, Richard Greenwood, David Skuse, & Zhenyu Jason Zhang, Carbohydrate Polymers , Vol.337, 1 August 2024, 122085. Microfibrillated cellulose (MFC) is a bio-material produced by disintegrating cellulose fibres into fibrillar components. MFC could offer a sustainable solution to packaging needs since it can form an excellent barrier to oxygen. However, a comprehensive understanding of how MFC characteristics impact barrier properties of MFC films or coatings is required. This article critically reviews how the extent of separation of fibres into fibrils — and any resulting changes to the crystallinity and degree of polymerisation of cellulose — influences gas barrier properties of MFC films or coatings. Findings from publications investigating the barrier performance of MFC prepared through different processes intending to increase the effectiveness of fibrillation are evaluated and compared. The effects of processing conditions or chemical pre-treatments on barrier properties of MFC films or coatings are then discussed. A comparison of reported results showed that morphology and size polydispersity of the cellulose strongly influence the barrier properties of MFC. However, changing the MFC production process to decrease fibril diameter and polydispersity can result in changes to cellulose crystallinity; reduction in fibril length; introduction of bulky functional groups; or increased fibril surface charge: all of which could have a negative impact on the barrier properties of the final films or coatings. “A review on the enhancement of circular economy aspects focusing on nanocellulose composites”, Muhammad Adlan Azka, Adib Adam, S.M. Ridzuan, S.M. Sapuan & Abdul Habib, International Journal of Biological Macromolecules , Vol.269(Pt.1), June 2024, 132052. Researchers are now focusing on using the circular economy model to manufacture nanocellulose composites due to growing environmental
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Technical Abstracts
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