@article{gaynor_agwuncha_smith_gaynor_harrington_lucia_2024, title={Alkaline pretreatment and soda pulping of genetically improved hemp}, volume={211}, ISSN={["1872-633X"]}, DOI={10.1016/j.indcrop.2024.118181}, abstractNote={Hemp has become increasingly important as an alternative fiber source for papermaking. However, a substantial knowledge gap for future applications of hemp fibers remains, specifically in pulping as a processing technology. Thus, significant research into optimal pulping methods must be performed to identify processing conditions that produce viable hemp pulps for papermaking applications. The literature has clearly identified the short fiber length of hemp hurd as a major obstacle to effective papermaking as understood from a strength perspective and has been a limitation to any significant work in this arena. To address this issue, genetic improvement efforts were previously undertaken to lengthen the hurd fibers, yet, additional research is needed to understand how to process these new hemp cultivars. Due to their simplicity, soda pretreatment and pulping were chosen as initial processes to investigate. Mild soda pretreatments were investigated as a method to reduce the chip particle size which decreases both liquor penetration distance and pulping time for a subsequent delignification stage. Chip size reduction was observed under multiple experimental conditions however, 12% sodium hydroxide (NaOH) performed the best. Fiber Quality Analyzer (FQA) analyses of soda pulped hemp stalks from improved cultivars resulted in hurd fiber lengths of approximately 1.0–1.2 mm. These fibers are significantly longer than those observed in traditional hurd pulp and comparable to fiber lengths of hardwood pulps. The chemical composition analyses of the raw, pretreated, and pulped hemp reinforced the importance of size reduction pretreatments and treatment severity. At the same processing conditions, larger chips experienced less delignification and xylan removal than smaller chips. Traditional pulping was significantly more effective at delignification than the mild pretreatment and resulted in a hemp sample with three to four times less lignin. The pretreatment and pulping results indicate a promising future direction for hemp in the field of papermaking using genetically improved cultivars.}, journal={INDUSTRIAL CROPS AND PRODUCTS}, author={Gaynor, J. Gavin and Agwuncha, Stephen C. and Smith, Alyssa and Gaynor, Gavin and Harrington, Michael J. and Lucia, Lucian}, year={2024}, month={May} }
 @misc{gaynor_szlek_kwon_tiller_byington_argyropoulos_2022, title={Lignin Use in Nonwovens: A Review}, volume={17}, ISSN={["1930-2126"]}, DOI={10.15376/biores.17.2.Gaynor}, abstractNote={While lignin has been gaining wide research interest for a variety of applications across many industries, relatively little work has been published on its applications in nonwovens. Consequently, this article offers an overview of the underlying principles and both the present and future applications of lignin within the nonwoven industry. Due to the distinct structure of lignin, processing, fiber production, composites with polymers, dye dispersant, and fire-retardant applications are all unique opportunities for lignin application in nonwovens discussed in this review. Conventional nonwoven processing techniques, such as electrospinning, have been reported to successfully produce lignin-based nonwovens, specifically lignin/polymer composite nonwovens. This account points to pivotal polymer matrix/lignin composite compatibility issues that define various processing technologies. However, lignin use is not limited to incorporation within nonwoven fibers mats and is currently used in dye dispersion with the potential of phase out petroleum-based dye dispersants. Finally, the high phenolic content of lignin endows it with fire-retardant and antimicrobial properties, among others, that present additional opportunities for lignin in the nonwoven industry. Throughout this review, an effort is made to outline the advantages and challenges of using lignin as a green and sustainable ingredient for the production of nonwoven materials.}, number={2}, journal={BIORESOURCES}, author={Gaynor, J. Gavin and Szlek, Dorota B. and Kwon, Soojin and Tiller, Phoenix S. and Byington, Matthew S. and Argyropoulos, Dimitris S.}, year={2022}, month={May}, pages={3445–3488} }