@article{wang_hu_lu_wang_zhang_tian_guo_song_jin_xiao_2021, title={Impact of degree of substitution of cationic xylan on strength of cellulose fiber networks along with medium conductivity}, volume={159}, ISSN={["1872-633X"]}, DOI={10.1016/j.indcrop.2020.113058}, abstractNote={Hemicelluloses have been considered as an efficient component to improve the bonding or strength of fiber networks. The degree of substitution (DS) of cationic hemicelluloses and the ionic strength of applied medium are therefore two most important and crucial factors influencing its performance in wet-end of papermaking. Therein, the impact of DS of cationic xylan (CX) derived from corncob on the strength of fiber networks was systematically explored in aqueous media with various ionic strengths. Initially, a series of CXs with DS ranging from 0.051 to 0.113 were synthesized via a microwave-assisted method. The resulting CXs were applied as wet-end additives in the media with conductivity of 500, 2500, and 5000 μs/cm, representing the low, moderate, and high level of electrolytes in closed white water circulation, respectively. Comparing to the control, all CXs improved the tensile and tear strength of paper significantly, while not in burst strength. The medium conductivity had an adverse impact on the performance of CXs, and the optimum DS of CXs was down shifted to about 0.05 ∼ 0.06. To mimic the adsorption of CXs on fiber surface, the adsorption behavior of CXs on negatively charged gold sensor was monitored by SPR in an attempt to reveal the mechanism. It was found that CXs with low DS had a larger adsorption capacity, thicker and softer adlayer, which are beneficial to fiber bonding and paper strength. This study is meaningful to the applications of xylan into value-added products and to the valorization of agricultural and forestry wastes.}, journal={INDUSTRIAL CROPS AND PRODUCTS}, author={Wang, Xiaoyan and Hu, Fanghui and Lu, Xiaomin and Wang, Qingcheng and Zhang, Xinyu and Tian, Jing and Guo, Jiaqi and Song, Junlong and Jin, Yongcan and Xiao, Huining}, year={2021}, month={Jan} }
 @article{song_salas_rojas_2015, title={Role of textile substrate hydrophobicity on the adsorption of hydrosoluble nonionic block copolymers}, volume={454}, ISSN={["1095-7103"]}, DOI={10.1016/j.jcis.2015.04.061}, abstractNote={The adsorption of polyalkylene glycols and co-polymers of ethylene oxide and propylene oxide on substrates relevant to textiles with varying surface energies (cellulose, polypropylene, nylon and polyester) was studied by using quartz crystal microgravimetry. Langmuirian-type isotherms were observed for the adsorption profiles of nonionic block polymers of different architectures. The affinity with the surfaces is discussed based on experimental observations, which highlights the role of hydrophobic effects. For a given type of block polymer, micellar and monomeric adsorption is governed by the balance of polymer structure (mainly, chain length of hydrophobic segments) and substrate's surface energy.}, journal={JOURNAL OF COLLOID AND INTERFACE SCIENCE}, author={Song, Junlong and Salas, Carlos and Rojas, Orlando J.}, year={2015}, month={Sep}, pages={89–96} }
 @article{song_krause_rojas_2014, title={Adsorption of polyalkyl glycol ethers and triblock nonionic polymers on PET}, volume={420}, ISSN={["1095-7103"]}, DOI={10.1016/j.jcis.2014.01.012}, abstractNote={Surface modification enables fiber lubrication and processing but little is known about the extent and dynamics of adsorption of typical adsorbates applied for such purposes, which often includes water-soluble block nonionic amphiphilic polymers. In this work we used quartz crystal microgravimetry (QCM) to investigate the adsorption on poly(ethylene terephthalate) (PET) of polyalkyl glycol ethers and triblock molecules of ethylene oxide and propylene oxide. The adsorption from aqueous solution of the block nonionic amphiphilic polymers strongly correlated with the self-association driven by the chain length of the respective hydrophobic blocks. This was demonstrated for the different adsorbing polymers using hydrophobic numbers calculated from simple group contribution methods. Hydrophobic and van der Waals interactions explain the affinity of the nonionic polymers with PET, which lead to adsorption isotherms that follow Langmuir-based and one-step empirical adsorption models.}, journal={JOURNAL OF COLLOID AND INTERFACE SCIENCE}, author={Song, Junlong and Krause, Wendy E. and Rojas, Orlando J.}, year={2014}, month={Apr}, pages={174–181} }
 @article{li_liu_song_rojas_hinestroza_2011, title={Adsorption and Association of a Symmetric PEO-PPO-PEO Triblock Copolymer on Polypropylene, Polyethylene, and Cellulose Surfaces}, volume={3}, ISSN={["1944-8244"]}, DOI={10.1021/am200264r}, abstractNote={The association of a symmetric polyoxyethylene-polyoxypropylene-polyoxyethylene (PEO(19)-PPO(29)-PEO(19)) triblock copolymer adsorbed from aqueous solutions onto polypropylene (PP), polyethylene (PE), and cellulose surfaces was probed using Atomic Force Microscopy (AFM). Significant morphological differences between the polyolefin substrates (PP and PE) and the cellulose surfaces were observed after immersion of the films in the PEO(19)-PPO(29)-PEO(19) solutions. When the samples were scanned, while immersed in solutions of the triblock copolymer, it was revealed that the structures adsorbed on the polyolefin surfaces were smoothed by the adsorbed PEO(19)-PPO(29)-PEO(19). In contrast, those structures on the hydrophilic cellulose surfaces were sharpened. These observations were related to the roughness of the substrate and the energy of interaction between the surfaces and the PEO and PPO polymer segments. The interaction energy between each of the blocks and the surface was calculated using molecular dynamics simulations. It is speculated that the associative structures amply reported in aqueous solution at concentrations above the critical micelle concentration, CMC, are not necessarily preserved upon adsorption; instead, it appears that molecular arrangements of the anchor-buoy type and hemimicelles prevail. The reported data suggests that the roughness of the surface, as well as its degree of hydrophobicity, have a large influence on the nature of the resulting adsorbed layer. The reported observations are valuable in explaining the behavior of finishing additives and lubricants commonly used in textile and fiber processing, as well as the effect of the morphology of the boundary layers on friction and wear, especially in the case of symmetric triblock copolymers, which are commonly used as antifriction, antiwear additives.}, number={7}, journal={ACS APPLIED MATERIALS & INTERFACES}, author={Li, Yan and Liu, Hongyi and Song, Junlong and Rojas, Orlando J. and Hinestroza, Juan P.}, year={2011}, month={Jul}, pages={2349–2357} }
 @article{song_yamagushi_silva_hubbe_rojas_2010, title={Effect of Charge Asymmetry on Adsorption and Phase Separation of Polyampholytes on Silica and Cellulose Surfaces}, volume={114}, ISSN={["1520-6106"]}, DOI={10.1021/jp909047t}, abstractNote={The relation between the properties of polyampholytes in aqueous solution and their adsorption behaviors on silica and cellulose surfaces was investigated. Four polyampholytes carrying different charge densities but with the same nominal ratio of positive to negative segments and two structurally similar polyelectrolytes (a polyacid and a polybase) were investigated by using quartz crystal microgravimetry using silica-coated and cellulose-coated quartz resonators. Time-resolved mass and rigidity (or viscoelasticity) of the adsorbed layer was determined from the shifts in frequency (Deltaf) and energy dissipation (DeltaD) of the respective resonator. Therefore, elucidation of the dynamics and extent of adsorption, as well as the conformational changes of the adsorbed macromolecules, were possible. The charge properties of the solid surface played a crucial role in the adsorption of the studied polyampholytes, which was explained by the capability of the surface to polarize the polyampholyte at the interface. Under the same experimental conditions, the polyampholytes had a higher nominal charge density phase-separated near the interface, producing a soft, dissipative, and loosely bound layer. In the case of cellulose substrates, where adsorption was limited, electrostatic and polarization effects were concluded to be less significant.}, number={2}, journal={JOURNAL OF PHYSICAL CHEMISTRY B}, author={Song, Junlong and Yamagushi, Takashi and Silva, Deusanilde J. and Hubbe, Martin A. and Rojas, Orlando J.}, year={2010}, month={Jan}, pages={719–727} }
 @article{liu_song_wu_genzer_theyson_rojas_2010, title={Surface and Friction Behavior of a Silicone Surfactant Adsorbed on Model Textiles Substrates}, volume={49}, ISSN={["0888-5885"]}, DOI={10.1021/ie1012213}, abstractNote={This study reports on interactions of an amphiphilic block copolymer of polyalkylene oxide-modified poly(dimethylsiloxane) with thin films of polypropylene (PP), polyethylene terephthalate (PET), and nylon, as well as with reference hydrophilic silica surfaces. The dynamics of adsorption, adsorbed mass, and viscoelasticity of the adsorbed layer are quantified by using a quartz crystal microbalance, while boundary layer lubrication behaviors are studied by using lateral force microscopy. Driven by hydrophobic interactions, the silicone surfactant adsorbs following a Langmuir isotherm and forms strongly adsorbed layers on the polymer surfaces with an areal mass directly related to the hydrophobicity of the substrate. The self-assembled silicone surfactant molecules improve significantly wettability and lower friction. The results reported herein will broaden our understanding of lubrication phenomena in textile and fiber processing applications.}, number={18}, journal={INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH}, author={Liu, Xiaomeng and Song, Junlong and Wu, Dong and Genzer, Jan and Theyson, Thomas and Rojas, Orlando J.}, year={2010}, month={Sep}, pages={8550–8557} }
 @article{song_liang_liu_krause_hinestroza_rojas_2009, title={Development and characterization of thin polymer films relevant to fiber processing}, volume={517}, ISSN={["0040-6090"]}, DOI={10.1016/j.tsf.2009.03.015}, abstractNote={Dilute solutions of cellulose, polypropylene, polyethylene, nylon and polyester were spun cast onto gold and silica wafers to generate thin films of these polymers, which are commonly used in the manufacture of synthetic fibers. The thin films were used as substrates in the quartz crystal microbalance and nano-indentation techniques to monitor adsorption and friction behaviors after treatment with a polymer solution (as a mimic of a textile finish). The spin coating conditions were optimized in terms of the resulting film morphology, thickness and surface energy. Atomic force microscopy, X-ray photoelectron spectrometry, ellipsometry and contact angle were used to probe the physical and surface properties of the resulting films. Overall, we developed thin films that are helpful to inquire, at the molecular level, phenomena relevant to fiber and textile processing including swelling, degradation, and adsorption of polymers and surfactants.}, number={15}, journal={THIN SOLID FILMS}, author={Song, Junlong and Liang, Jing and Liu, Xiaomeng and Krause, Wendy E. and Hinestroza, Juan P. and Rojas, Orlando J.}, year={2009}, month={Jun}, pages={4348–4354} }
 @article{silva_rojas_hubbe_park_yamaguchi_song_2009, title={Polyampholytes: Their use in papermaking and their solution and adsorption behaviors}, volume={70}, number={9}, journal={O Papel}, author={Silva, D. J and Rojas, O. J. and Hubbe, M. A and Park, S. W. and Yamaguchi, T. and Song, J.}, year={2009}, pages={40–50} }
 @article{hubbe_rojas_argyropoulos_wang_song_sulic_sezaki_2007, title={Charge and the dry-strength performance of polyampholytes. Part 2. Colloidal effects}, volume={301}, DOI={10.1016/j.colsurfa.2006.11.053}, abstractNote={Polyampholytes, which are macromolecules that contain both positive and negative ionizable groups, can provide superior strength improvements for paper manufacture, compared to the addition of simple polyelectrolytes. Colloidal effects, which were measured in solution and in fiber suspensions, were consistent with observed bonding effects. The same colloidal effects were found to correlate with the effects of pH and of the density of the ionizable groups on the polyampholytes. Tests were carried out with a series of polyampholytes having a constant ratio of cationic to anionic monomeric groups and molecular mass. Their charge density varied in the ratio 1:2:4:8. The greatest strength gains were obtained at intermediate charge density and under conditions of pH favoring instability of the aqueous polymer mixtures. Colloidal phenomena were elucidated by turbidimetric tests, sediment volumes of treated fiber suspensions, flocculation tendencies of treated fiber suspensions, and zeta potentials of probe particles.}, journal={Colloids and Surfaces. A, Physicochemical and Engineering Aspects}, author={Hubbe, M. A. and Rojas, O. J. and Argyropoulos, Dimitris and Wang, Y. and Song, J. and Sulic, N. and Sezaki, T.}, year={2007}, pages={23–32} }
 @inbook{lucian_argyropoulos_ban_song_2007, title={Modifying the functionality of starch films with natural polymers}, volume={954}, ISBN={9780841239814}, DOI={10.1021/bk-2007-0954.ch013}, abstractNote={The physical and chemical properties of composite starch-based films containing cellulosic fiber, chitosan, and gelatin were investigated. Films containing both cellulosic fibers and chitosan demonstrated tremendous enhancements in film strength and gas permeation. The water absorbency of composite films could be greatly reduced in film composites containing cellulosic fibers and gelatin, but the inclusion of chitosan into these films provided a higher hydrophilicity, increasing water absorbency. Film transparency was not noticeably affected in the composite films that were made. These films may have wide application in the food packaging, agricultural mulching, and the biomedical industries.}, booktitle={Materials, chemicals and energy from forest biomass}, publisher={Washington, DC: ACS Books}, author={Lucian, A. L. and Argyropoulos, Dimitris and Ban, W. and Song, J.}, year={2007}, pages={200–218} }
 @article{song_wang_hubbe_rojas_sulic_sezaki_2006, title={Charge and the dry-strength performance of polyampholytes. Part 1, Handsheet properties and polymer solution viscosity}, volume={32}, number={3}, journal={Journal of Pulp and Paper Science}, author={Song, J. and Wang, Y. and Hubbe, M. A. and Rojas, O. J. and Sulic, N. and Sezaki, T.}, year={2006}, pages={156–162} }
 @article{rojas_song_argyropoulos_2006, title={Lignin separation from kraft black liquors by tangential ultrafiltration}, volume={88}, number={1}, journal={Chimica E L'industria}, author={Rojas, O. J. and Song, J. and Argyropoulos, D. S.}, year={2006}, pages={88–95} }
 @article{ban_song_lucia_2004, title={Insight into the chemical behavior of softwood carbohydrates during high-sulfidity green liquor pretreatment}, volume={43}, ISSN={["0888-5885"]}, DOI={10.1021/ie034030x}, abstractNote={About 20% of the total wood carbohydrates removed from softwood chips from a pretreatment with a high-sulfidity, carbonate-rich solution known as green liquor (GL) are mainly derived from glucose and mannose. The salient chemical events occurring during GL pretreatment are sugar readsorption in a neutral or slightly alkaline environment and substantial mannan dissolution. However, it appears that pentose saccharides are more easily adsorbed onto fibers than hexose saccharides. Mannose, for example, undergoes degradation easily, with no obvious readsorption during the entire process. A higher GL concentration can enhance both tendencies of reabsorption and degradation. A striking finding is that, during the pretreatment phase, hydrogen sulfide appears to react with wood composites to form a very tight bond that appears to be chemical in nature. The apparent chemical bonding behavior of sulfur in wood correlates with carbohydrates retention: a higher level of bonded sulfur results in higher carbohydrates retention. Finally, various additives applied during GL pretreatment were found to exert a significant influence on sugar retention.}, number={6}, journal={INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH}, author={Ban, W and Song, J and Lucia, LA}, year={2004}, month={Mar}, pages={1366–1372} }
 @misc{song_rojas, title={Approaching super-hydrophobicity from cellulosic materials: A Review}, volume={28}, number={2}, journal={Nordic Pulp & Paper Research Journal}, author={Song, J. L. and Rojas, O. J.}, pages={216–238} }