Fast Track to Molar‐Mass Distributions of Technical Lignins

Sulaeva, Irina; Zinovyev, Grigory; Plankeele, Jean-Michel; Sumerskii, Ivan; Rosenau, Thomas; Potthast, Antje

doi:10.1002/cssc.201601517

Cited by 43 publications

(58 citation statements)

References 25 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The columns were calibrated using polystyrene sulfonate standards (Na‐PSS) of narrow molecular weight distribution ( Ð ≤ 1.20; M w 1100, 1920, 3610, 6520, 14,900, 29,100, 63,900, 148,000 g mol −1 ). Solubilization of PSS standards in DMSO was achieved by pretreatment with acidic cation‐exchange resin as described elsewhere . Data evaluation was performed using Empower 3 Chromatography Data Software.…”

Section: Methodsmentioning

confidence: 99%

“…Solubilization of PSS standards in DMSO was achieved by pretreatment with acidic cationexchange resin as described elsewhere. 10 Data evaluation was performed using Empower 3 Chromatography Data Software. 31 P NMR analysis was performed as described elsewhere 11,12 using TMDP as phosphitylation reagent to label all free hydroxyl groups present in the respective lignins and the solvent mixture M (CDCl 3 /pyridine, 1:1.6, v/v) to prepare the following solutions: (A) analyte solution containing 35 mg mL 21 lignin; (B) standard stock solution containing 50 mg mL 21 cholesterol and 30 mg mL 21 N-hydroxy-5-norbornene-2,3-dicarboxylic acid imide; (C) relaxation reagent solution containing 5 mg mL 21 of chromium (lll) acetylacetonate.…”

Section: Methodsmentioning

confidence: 99%

See 1 more Smart Citation

Commercial lignosulfonates from different sulfite processes as partial phenol replacement in PF resole resins

Ghorbani

Konnerth

Herwijnen

et al. 2017

J of Applied Polymer Sci

Self Cite

View full text Add to dashboard Cite

Four commercial spruce lignosulfonates representing the most common acidic, neutral, and alkaline sulfite pulping processes and varying significantly in molecular weight characteristics were tested as partial (40 wt %) phenol substitute materials for the manufacture of lignosulfonate‐phenol‐formaldehyde (LPF) resole resins. Similar as recently reported for technical lignins from nonsulfite pulping processes (kraft, soda, organosolv), all lignosulfonates of this study effectuated a faster viscosity gain during resole cooking compared to the lignin‐free reference resin (1000 mPa s after 120 min vs. 250 min to reach 1000 mPa s). Sodium lignosulfonate featuring the lowest weight average molecular weight (Mw 5780 g mol−1) and dispersity (Ð 6.1) turned out to be superior to the other lignosulfonates with regard to curing rate (B‐time; 3:37 min vs. 6:41–9:08 min) and tensile shear strength development under hot pressing (120 °C; TS,max = 5.64 N mm−2 after 8 min) for beech veneer strips glued together with the respective LPF resins. Calcium and magnesium lignosulfonates are less suited with regard to phenol replacement due to the poor performance of the respective LPF adhesives in terms of tensile shear strength (TS,max = 3.29–3.49 N mm−2 after 12 min) most likely caused by considerable amounts of side products formed in the course of formose‐type reactions. Phenolation of the two promising lignosulfonates, that is, sodium and ammonium lignosulfonate, did neither considerably increase the rate of PF network formation during resin cooking and curing nor improve tensile strength development during hot pressing. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 45893.

show abstract

Section: Methodsmentioning

confidence: 99%

Section: Methodsmentioning

confidence: 99%

Commercial lignosulfonates from different sulfite processes as partial phenol replacement in PF resole resins

Ghorbani

Konnerth

Herwijnen

et al. 2017

J of Applied Polymer Sci

Self Cite

View full text Add to dashboard Cite

show abstract

“…Recently,asimple protocol employing aN a-PSS protonation procedure has been proposed allowing for the complete dissolution of protonated PSS in DMSO. [21] Considering that DMSO is au niversal solvent system capable of dissolving almosta ll lignin types, the SEC setup with DMSO as the eluent and PSSbased calibrationr epresents ar easonable approach to lignosulfonate characterization. However,t he errors in lignin molar mass calculations, as ar esult of the structural dissimilarities between calibranta nd analyte, remainq uite large.…”

Section: Shortcomings and Limitations Of Conventional Approaches To Mmentioning

confidence: 99%

“…Because no lignin SEC standards are available, the molar mass is assessed based on narrow polystyrene (PS) standards or PS sulfonate (PSS) standards in the case of lignosulfonates. To avoid any confusion, we would like to point out that polystyrene is insoluble in DMSO, but PSS can be dissolved 21. Our point assumes that, among the suitable standard compounds commercially available, these polymers structurally resemble the lignin molecules most closely.…”

Section: Introductionmentioning

confidence: 99%

“…To avoid any confusion, we would like to point out that polystyrene is insoluble in DMSO, but PSS can be dissolved. [21] Our point assumes that, among the suitable standard compounds commercially available, these polymers structurally resemble the lignin molecules most closely.H owever,a pplying this calibration approach shows that the hydrodynamic radii of lignin and PSS molecules, which are the basis of the SEC elution behavior,a re not sufficiently comparable. This differencer esultsf rom the different molecular structure and its arrangement in solution and causes considerable deviations between the true lignin molar mass and the values obtained according to the calibration ap-proach.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Getting Closer to Absolute Molar Masses of Technical Lignins

et al. 2018

Self Cite

View full text Add to dashboard Cite

Determination of molecular weight parameters of native and, in particular, technical lignins are based on size exclusion chromatography (SEC) approaches. However, no matter which approach is used, either conventional SEC with a refractive index detector and calibration with standards or multi‐angle light scattering (MALS) detection at 488 nm, 633 nm, 658 nm, or 690 nm, all variants can be severely erroneous. The lack of calibration standards with high structural similarity to lignin impairs the quality of the molar masses determined by conventional SEC, and the typical fluorescence of (technical) lignins renders the corresponding MALS data rather questionable. Application of MALS detection at 785 nm by using an infrared laser largely overcomes those problems and allows for a reliable and reproducible determination of the molar mass distributions of all types of lignins, which has been demonstrated in this study for various and structurally different analytes, such as kraft lignins, milled‐wood lignin, lignosulfonates, and biorefinery lignins. The topics of calibration, lignin fluorescence, and lignin UV absorption in connection with MALS detection are critically discussed in detail, and a reliable protocol is presented. Correction factors based on MALS measurements have been determined for commercially available calibration standards, such as pullulan and polystyrene sulfonate, so that now more reliable mass data can be obtained also if no MALS system is available and these conventional calibration standards have to be resorted to.

show abstract

Lignosulfonate‐Derived Conducting Organohydrogel as Anisotrpic Bioadhesive for Motion‐Artifact‐Free Epidermal Bioelectronics

Shen,

Cai,

et al. 2024

Adv Funct Materials

View full text Add to dashboard Cite

Gel‐based adhesives show promising prospects in epidermal bioelectronics because of their potential applications in physiological signal collection and electrical stimulation. An ideal epidermal adhesive should exhibit robust adhesion for lamination and poor adhesion for easy peeling, in addition to strain‐insensitivity in electrical properties for motion‐artifact‐free physiological signal collection. Here, lignosulfonate‐derived organohydrogel adhesives with anisotropic and tunable adhesion, together with unprecedented strain‐insensitivity are synthesized. The organohydrogel exhibits a high interfacial toughness of 728 J m−2 on fresh porcine skin, while the adhesion can be screened by covering a denatured silk fibroin. An anisotropic adhesive with an adhesion heterogeneity is designed, showing a 14.2‐fold difference in adhesion strength along two different directions for on‐demand attachment and removal. The adhesive can transform into a highly porous structure, which has only a 3% resistance increase at 100% strain. The strain‐insensitivity of the adhesive lies in the strong interaction of ions and the 3D porous structure, which enables motion‐artifact‐free and high‐quality electrophysiological signal collection within the strain range of the human skin. The lignosulfonate‐derived on‐demand organohydrogel adhesive is expected to be used in epidermal bioelectronics, human‐machine interaction, metaverse, and beyond.

show abstract

Fast Track to Molar‐Mass Distributions of Technical Lignins

Cited by 43 publications

References 25 publications

Commercial lignosulfonates from different sulfite processes as partial phenol replacement in PF resole resins

Commercial lignosulfonates from different sulfite processes as partial phenol replacement in PF resole resins

Getting Closer to Absolute Molar Masses of Technical Lignins

Lignosulfonate‐Derived Conducting Organohydrogel as Anisotrpic Bioadhesive for Motion‐Artifact‐Free Epidermal Bioelectronics

Contact Info

Product

Resources

About