@article{starkey_chenoweth_johnson_salem_jameel_pal_2021, title={Lignin-containing micro/nanofibrillated cellulose to strengthen recycled fibers for lightweight sustainable packaging solutions}, volume={2}, ISSN={["2666-8939"]}, url={http://dx.doi.org/10.1016/j.carpta.2021.100135}, DOI={10.1016/j.carpta.2021.100135}, abstractNote={As e-commerce drives the packaging growth, consumers are pushing for more sustainable packaging solutions. Considering the current societal needs, we have been able to engineer a new pathway for sustainable packaging solutions by developing lignin-containing micro- and nano-fibrillated cellulosic (LMNFCs) materials to strengthen the recycled fibers. LMNFCs from unbleached softwood pulp containing 14.4% lignin at high and low fibrillation levels were produced. Packaging papers from recycled old-corrugated containers were strengthened with LMNFCs with varying addition levels of 1 wt% to 3 wt% at two basis weights. The results show 2 wt% addition of LMNFC can enhance strength at low levels of fibrillation, and that basis weight can be reduced by 16.7%, from 150 gsm to 125 gsm, while maintaining a burst strength of 49-53 lbf. Reduction in basis weight and high lignin content of LMNFC also enhanced dewatering during sheet formation with the lowest increase in drainage time, 9%, relative to the 150 gsm with no LMNFC. The techno-economic analysis supports the feasibility of using LMNFC to produce lightweight and sustainable packaging materials at industrial scale with an 8% reduction in fiber cost.}, journal={CARBOHYDRATE POLYMER TECHNOLOGIES AND APPLICATIONS}, publisher={Elsevier BV}, author={Starkey, Heather and Chenoweth, Audra and Johnson, Christopher and Salem, Khandoker Samaher and Jameel, Hasan and Pal, Lokendra}, year={2021}, month={Dec} }
 @article{salem_starkey_pal_lucia_jameel_2019, title={The Topochemistry of Cellulose Nanofibrils as a Function of Mechanical Generation Energy}, volume={8}, ISSN={2168-0485 2168-0485}, url={http://dx.doi.org/10.1021/acssuschemeng.9b05806}, DOI={10.1021/acssuschemeng.9b05806}, abstractNote={Nanofibrillated cellulose (NFC) has garnered significant attention as a sustainable biomaterial, but its chemical reactivity with respect to its generation, i.e., fibrillation, has heretofore been unexplored. We prepared NFC samples with varying levels of fibrillation by controlling mechanical energy followed by acetylation as a probe to explore chemical reactivity. The degree of substitution (DS) reached a global maximum after which, surprisingly, it dropped to lower values at higher fibrillation or higher input (generation) energies. This behavior was attributed to two factors: the presence of higher bound water molecules at fibrillated surfaces, which hinder accessibility to cellulose chains, and enhanced self-aggregation of surface hydroxyl groups of NFC due to formation of hydrogen bonds at higher fibrillation. The discovery of these two mitigating factors provides a promising physicochemical strategy for efficient and sustainable production and modification of NFC to optimize performance for different applications.}, number={3}, journal={ACS Sustainable Chemistry & Engineering}, publisher={American Chemical Society (ACS)}, author={Salem, Khandoker Samaher and Starkey, Heather R. and Pal, Lokendra and Lucia, Lucian and Jameel, Hasan}, year={2019}, month={Dec}, pages={1471–1478} }