@article{kwon_zambrano_pawlak_ford_venditti_2024, title={Aquatic biodegradation of poly(β-hydroxybutyrate) in polylactic acid and maleic anhydride blended fibers}, volume={31}, ISSN={["1572-8935"]}, DOI={10.1007/s10965-024-03930-8}, number={4}, journal={JOURNAL OF POLYMER RESEARCH}, author={Kwon, Soojin and Zambrano, Marielis C. and Pawlak, Joel J. and Ford, Ericka and Venditti, Richard A.}, year={2024}, month={Apr} }
 @article{kwon_zambrano_venditti_pawlak_2023, title={Aerobic aquatic biodegradation of bio-based and biodegradable polymers: Kinetic modeling and key factors for biodegradability}, volume={185}, ISSN={["1879-0208"]}, url={https://doi.org/10.1016/j.ibiod.2023.105671}, DOI={10.1016/j.ibiod.2023.105671}, abstractNote={With the increasing concern about plastic waste, numerous efforts have been made to find substitutes for existing non-biodegradable synthetic polymers. Bio-based and/or purported petroleum-based biodegradable polymers are considered probable plastic replacement candidates. However, the durability of non-biodegradable plastic is a key feature of plastics. Thus, a balance must be achieved between biodegradation and environmental material stability. The objective of this study is to determine the impact of crystallinity, molecular chemistry, and hydrophilicity on the rate of aquatic biodegradation of biobased plastic materials. In the present study, twelve bio-based/purported biodegradable materials were investigated under aerobic aquatic biodegradation conditions for 56 days by tracking oxygen consumption. Crystallinity, hydrophobicity, chemistry, and chemical structure were varied to understand potential means for controlling the rate of biodegradation. The biodegradation kinetics were analyzed and discussed, relating to the characteristics of polymers. Polyvinyl alcohol (PVA), Chitosan, Rayon, Polyhydroxy-butyrate-co-valerate (PHBV), PHBH, and Polybutylene succinate (PBS) showed the biodegradation extents over 70% at 56 days. Cellulose acetates (CAs) and Polylactic acid (PLA) showed biodegradation extent lower than 20%. The chemistry of the polymer backbone chain, substituent structure, and degree of substitution were the dominant factors affecting biodegradation. The crystallinity of the polyesters had a negative correlation with the initial biodegradation rate and the ultimate biodegradation of polyesters, and the hydrophobicity of the polymers delayed the initiation of biodegradation. The aerobic aquatic biodegradation results related to the polymer characteristics are useful for product designers and environmental scientists to understand the fate of these polymeric materials in the environment.}, journal={INTERNATIONAL BIODETERIORATION & BIODEGRADATION}, author={Kwon, Soojin and Zambrano, Marielis C. and Venditti, Richard A. and Pawlak, Joel J.}, year={2023}, month={Nov} }
 @article{kwon_zambrano_pawlak_ford_venditti_2023, title={Aquatic Biodegradation of Poly(beta-Hydroxybutyrate) and Polypropylene Blends with Compatibilizer and the Generation of Micro- and Nano-Plastics on Biodegradation}, volume={4}, ISSN={["1572-8919"]}, DOI={10.1007/s10924-023-02832-y}, journal={JOURNAL OF POLYMERS AND THE ENVIRONMENT}, author={Kwon, Soojin and Zambrano, Marielis C. C. and Pawlak, Joel J. J. and Ford, Ericka and Venditti, Richard A. A.}, year={2023}, month={Apr} }
 @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} }
 @article{kwon_zambrano_venditti_frazier_zambrano_gonzalez_pawlak_2022, title={Microfiber shedding from nonwoven materials including wipes and meltblown nonwovens in air and water environments}, volume={4}, ISSN={["1614-7499"]}, DOI={10.1007/s11356-022-20053-z}, abstractNote={Nonwoven products are widely used in disposable products, such as wipes, diapers, and masks. Microfibers shed from these products in the aquatic and air environment have not been fully described. In the present study, 15 commercial single-use nonwoven products (wipes) and 16 meltblown nonwoven materials produced in a pilot plant were investigated regarding their microfiber generation in aquatic and air environments and compared to selected textile materials and paper tissue materials. Microfibers shed in water were studied using a Launder Ometer equipment (1-65 mg of microfibers per gram material), and microfibers shed in air were evaluated using a dusting testing machine that shakes a piece of the nonwoven back and forth (~ 4 mg of microfibers per gram material). The raw materials and bonding technologies affected the microfiber generation both in water and air conditions. When the commercial nonwovens contained less natural cellulosic fibers, less microfibers were generated. Bonding with hydroentangling and/or double bonding by two different bonding methods could improve the resistance to microfiber generation. Meltblown nonwoven fabrics generated fewer microfibers compared to the other commercial nonwovens studied here, and the manufacturing factors, such as DCD (die-to-collector distance) and air flow rate, affected the tendency of microfiber generation. The results suggest that it is possible to control the tendency of microfiber shedding through the choice of operating parameters during nonwoven manufacturing processes.}, journal={ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH}, author={Kwon, Soojin and Zambrano, Marielis C. and Venditti, Richard A. and Frazier, Ryen and Zambrano, Franklin and Gonzalez, Ronalds W. and Pawlak, Joel J.}, year={2022}, month={Apr} }
 @article{shen_kwon_lae_toivakka_oh_2022, title={Preparation and application of composite phase change materials stabilized by cellulose nanofibril-based foams for thermal energy storage}, volume={222}, ISSN={["1879-0003"]}, DOI={10.1016/j.ijbiomac.2022.10.075}, abstractNote={The leakage issue and inferior heat conduction of organic phase change materials (PCMs) limit their actual applications. In the present study, cellulose nanofibril (CNF)-based foams were prepared as the porous scaffolds for polyethylene glycol (PEG) and paraffin wax (Pw) to prevent their leakage, and multiwalled carbon nanotubes (CNTs) were incorporated to improve the heat transfer performance. The prepared foams had low density (<67.3 kg/m3) and high porosity (>94.5 %). Selective chemical modifications of nanocellulose foams enhanced their shape-stability and compatibility with PCMs. The highly porous foam structure and favorable compatibility resulted in high PCM loading levels (93.63 % for PEG and 91.77 % for Pw) and negligible PCM leakage (<2 %). CNTs improved the heat transfer performance of PCMs, as evidenced by the improved thermal conductivities and boosted temperature rises during solar heating. Meanwhile, the composite PCMs exhibited improved thermal stability over the control. PEG-based composite PCM exhibited a phase change enthalpy of 143 kJ/kg with a melting temperature of 25.2 °C; Pw-based composite PCM exhibited a phase change enthalpy of 184 kJ/kg with a melting temperature of 53.4 °C. Novel PCM sandwich structures based on these composite PCMs and a thermoelectric generator were designed and displayed promising potential for solar energy harvesting and utilization.}, journal={INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES}, author={Shen, Zhenghui and Kwon, Soojin and Lae, Hak Lae and Toivakka, Martti and Oh, Kyudeok}, year={2022}, month={Dec}, pages={3001–3013} }
 @article{shen_kwon_lee_toivakka_oh_2021, title={Cellulose nanofibril/carbon nanotube composite foam-stabilized paraffin phase change material for thermal energy storage and conversion}, volume={273}, ISSN={["1879-1344"]}, DOI={10.1016/j.carbpol.2021.118585}, abstractNote={The leakage and low thermal conductivity of paraffin phase change material (PCM) must be addressed to achieve a more efficient energy storage process. In this study, cellulose nanofibril (CNF) foams were prepared as the porous support of paraffin to prevent its leakage, and multiwalled carbon nanotubes (CNTs) were incorporated in the foams to improve heat transfer performance. Treatment of CNF with methyltrimethoxysilane improved compatibility between the foams and paraffin. The prepared highly porous (porosity >96%) foams had paraffin absorption capacities exceeding 90%. The form-stable PCM composites displayed negligible paraffin leakage and had a compact structure. The prepared PCM composites had enhanced heat transfer performance, reasonable phase change properties and thermal stabilities. The enthalpy of the SCNF/CNT50-Pw PCM composite decreased by 6% after 100 melting/freezing cycles. Compared with pristine paraffin, the PCM composites exhibited superior form-stabilities and improved thermal properties, which suggested application in a solar-thermal-electricity energy harvesting and conversion system.}, journal={CARBOHYDRATE POLYMERS}, author={Shen, Zhenghui and Kwon, Soojin and Lee, Hak Lae and Toivakka, Martti and Oh, Kyudeok}, year={2021}, month={Dec} }
 @article{kwon_zambrano_pawlak_venditti_2021, title={Effect of lignocellulosic fiber composition on the aquatic biodegradation of wood pulps and the isolated cellulose, hemicellulose and lignin components: kinetic modelling of the biodegradation process}, volume={28}, ISSN={0969-0239 1572-882X}, url={http://dx.doi.org/10.1007/s10570-021-03680-6}, DOI={10.1007/s10570-021-03680-6}, number={5}, journal={Cellulose}, publisher={Springer Science and Business Media LLC}, author={Kwon, Soojin and Zambrano, Marielis C. and Pawlak, Joel J. and Venditti, Richard A.}, year={2021}, month={Feb}, pages={2863–2877} }
 @article{shen_kwon_lee_toivakka_oh_2021, title={Enhanced thermal energy storage performance of salt hydrate phase change material: Effect of cellulose nanofibril and graphene nanoplatelet}, volume={225}, ISSN={["1879-3398"]}, DOI={10.1016/j.solmat.2021.111028}, abstractNote={Thermal energy storage (TES) has attracted intense attention because of its positive contribution to sustainable energy utilization. To improve the TES performance of sodium acetate trihydrate (SAT), the combined use of cellulose nanofibril (CNF) and graphene nanoplatelet (GNP) was investigated to tackle the phase separation problem and to improve the thermal conductivity of SAT. Phase stability and rheology tests revealed that adding 0.8% of CNF to SAT increased viscosity, enhanced solid-like rheological behavior, and successfully eliminated phase separation. Meanwhile, the amphiphilicity of CNF facilitated the dispersion of GNP. Sodium phosphate dibasic dodecahydrate (DSP; Na2HPO4·12H2O) was selected as the nucleating agent, which reduced the supercooling degree of SAT to 2.1 °C. Phase change materials (PCMs) were prepared by simply blending GNP pre-dispersed with CNF, DSP, and SAT. Due to the excellent thermal performance of GNP and its good dispersion by CNF, the prepared PCM composites showed enhanced thermal conductivity compared with that of pure SAT. Thermal reliability testing indicated that the melting point and enthalpy of the prepared PCM composites decreased after 100 melting/freezing cycles. Overall, PCM composites with enhanced performance were fabricated based on renewable, bio-based, and biodegradable nanocellulose. These composites can be used for certain TES applications.}, journal={SOLAR ENERGY MATERIALS AND SOLAR CELLS}, author={Shen, Zhenghui and Kwon, Soojin and Lee, Hak Lae and Toivakka, Martti and Oh, Kyudeok}, year={2021}, month={Jun} }
 @article{oh_shen_kwon_toivakka_2021, title={Thermal properties of graphite/salt hydrate phase change material stabilized by nanofibrillated cellulose}, ISSN={["1572-882X"]}, DOI={10.1007/s10570-021-03936-1}, abstractNote={Thermal energy storage (TES) systems using phase change materials (PCMs) are of increasing interest for more efficient energy utilization. Herein, sodium sulfate decahydrate (Na2SO4·10H2O; SSD)/nanofibrillated cellulose (NFC)/graphite PCM composites were prepared by a simple blending method. NFC and graphite were used to improve the performance of SSD-based PCMs by mitigating the phase separation and low thermal conductivity issues. The phase stability, thermal, and structural properties of the prepared PCM composites were investigated. The role of NFC was to thicken and thereby improve phase stability, and to assist dispersion of hydrophobic graphite without aggregation by leveraging its amphiphilic characteristics. The supercooling degree, melting temperature, and enthalpy of 4.2 °C, 31.1 °C, and 121.7 J/g, respectively, were measured for the PCM containing 5 wt% of graphite. Fourier transform-infrared spectroscopy and X-ray diffraction studies indicated that no chemical reactions occurred between the PCM components. The thermal conductivity was enhanced by 250 % when 5 wt% of graphite was added, which improved heat charging during the melting process. Increased hydrogen bonding between fibrils and water molecules enhanced the thermal stability by suppressing water evaporation. Our results indicate that the composite would be an efficient TES system.}, journal={CELLULOSE}, author={Oh, Kyudeok and Shen, Zhenghui and Kwon, Soojin and Toivakka, Martti}, year={2021}, month={Jun} }
 @article{shen_oh_kwon_toivakka_lee_2021, title={Use of cellulose nanofibril (CNF)/silver nanoparticles (AgNPs) composite in salt hydrate phase change material for efficient thermal energy storage}, volume={174}, ISSN={["1879-0003"]}, DOI={10.1016/j.ijbiomac.2021.01.183}, abstractNote={Salt hydrate phase change materials (PCMs) possess the challenge of supercooling, which must be addressed to allow more efficient energy storage and utilisation. In this work, cellulose nanofibril (CNF), a versatile biopolymer was used to support and disperse silver nanoparticles (AgNPs), and the synthesised CNF/AgNPs composite was used to improve the performance of sodium acetate trihydrate (SAT). Results showed that CNF dispersed the AgNPs uniformly and prevented their aggregation. Through the synergistic effect of 1% CNF/AgNPs and 2% sodium phosphate dibasic dodecahydrate, a low supercooling degree of 1.2 °C was achieved. Moreover, AgNPs were uniformly distributed in the prepared PCM composite. Differential scanning calorimetry results indicated that the prepared [email protected]/AgNPs 0.02 composite showed a similar melting point (57.4 °C) and enthalpy (269 kJ/kg), compared to those of pure SAT. Thermogravimetric analysis showed that the PCM composite did not lose all moisture until a heating temperature of 160 °C, showing improved thermal stability. The thermal conductivity of [email protected]/AgNPs 0.02 composite was 31.6% higher than that of SAT. The enthalpy of this composite decreased only around 2% after 100 melting/freezing cycles, showing satisfying thermal reliability. This composite can therefore be used to fabricate high-performance TES systems with negligible supercooling and improved thermal properties.}, journal={INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES}, author={Shen, Zhenghui and Oh, Kyudeok and Kwon, Soojin and Toivakka, Martti and Lee, Hak Lae}, year={2021}, month={Mar}, pages={402–412} }