A light-colored hydroxypropyl sulfonated alkali lignin for utilization as a dye dispersant

The physico-chemical characterization of two types of alkali lignin from different origin, namely L1 and L2, were studied by Fourier transform infrared spectroscopy (FT-IR), proton nuclear magnetic resonance spectrometry (1H NMR) and gel permeation chromatography (GPC) analysis. FT-IR spectra show that they have the characteristics of absorption peaks of syringyl and guaiacyl. 1H NMR spectra indicate that acetylated L1 exhibits higher content of aromatic protons than L2, as the former is mainly composed by G units. L2 presents high quantities of methoxyl groups. GPC results show that L1 has much higher weight average than L2. They had similar functional groups, however, there were differences in the relative contents of functional groups.

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Enhanced Thermal Stability of Esterified Lignin in Different Solvent Mediums

Polymers from Renewable Resources ◽

10.1177/204124791800900103 ◽

2018 ◽

Vol 9 (1) ◽

pp. 39-49 ◽

Cited By ~ 1

Author(s):

Sharifah Nurul Ain Syed Hashim ◽

Sarani Zakaria ◽

Chin Hua Chia ◽

Sharifah Nabihah Syed Jaafar

Keyword(s):

Thermal Stability ◽

Alkaline Solution ◽

Room Temperature ◽

Hydroxyl Groups ◽

Aqueous Alkaline Solution ◽

Alkali Lignin ◽

Weight Percentage ◽

H Nmr ◽

Ft Ir ◽

Thermal Stability Of

In this study, soda alkali lignin from oil palm empty fruit bunch (EFB-AL) and kenaf core (KC-AL) are esterified with maleic anhydride under two different conditions, namely i) pyridine at temperature of 120°C for 3h and ii) aqueous alkaline solution at room temperature for 4h. As a result, the weight percentage gain (WPG) of the esterified EFB-AL (EFB-EL) and esterified KC-AL (KC-EL) in pyridine demonstrated a higher compared to aqueous alkaline solution. The FT-IR results of EFB-EL and KC-EL in both solvents exhibited some changes at the carbonyl and hydroxyl groups. Furthermore, the esterification process induced the carboxylic peak to appear in both alkali lignin samples. The outcome is confirmed by conducting H-NMR analysis, which demonstrated ester and carboxylic acid peaks within the spectral analysis. Finally, the TGA results showed both EFB-EL and KC-EL that are exposed to aqueous alkaline actually possessed better thermal stability and higher activation energy (Ea) compared to the esterified samples in pyridine.

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Reduction-Degradable Shell Cross-Linked Micelle with pH-Responsive Cores Prepared via Click Chemistry

Materials Science Forum ◽

10.4028/www.scientific.net/msf.848.527 ◽

2016 ◽

Vol 848 ◽

pp. 527-531

Author(s):

Lu Bin Lin ◽

Qing Yun Yu ◽

Zhuo Qun Gu ◽

Xiao Ze Jiang ◽

Mei Fang Zhu

Keyword(s):

Click Chemistry ◽

Self Assembly ◽

Gel Permeation Chromatography ◽

Proton Nuclear Magnetic Resonance ◽

Poly Ethylene Glycol ◽

H Nmr ◽

Transmission Electron ◽

Assembly Behavior ◽

Poly Ethylene ◽

Novel Drug

A well-defined poly [(ethylene glycol)-block-2-(dimethylamino) ethyl methacrylate-block-2-(diethylamino) methacrylate] (PEG-b-DMA-b-DEA) triblock copolymer was synthesized via atom transfer radical polymerization (ATRP) by successively polymerization of DMA and DEA monomers using a PEG-based macroinitiator, and obtained copolymer was then converted to be PEG-b-P(DMA-co-QDMA)-b-PDEA copolymer with “clickable” moieties in the middle block by the quaternization with propargyl bromide. Those copolymers prepared were characterized by proton Nuclear Magnetic Resonance (1H NMR) and Gel Permeation Chromatography (GPC), and its self-assembly behavior and subsequently fixation with bis-(azidoethyl) disulfide via click chemistry resulting reduction-sensitive shell-cross-linked (SCL) micelle in purely aqueous solution were investigated by Transmission Electron Microscopy (TEM) and Dynamic Light Scattering (DLS). The results show the micellar structure could be effectively cross-linked via click chemistry and also be dissociated at reduction condition, which may realize it's potential application as novel drug delivery carriers.

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Facile Synthesis, Characterization, and In Vitro Antimicrobial and Anticancer Activities of Biscoumarin Copolyester Bearing Pendant 3-(Trifluoromethyl)Styrene

International Scholarly Research Notices ◽

10.1155/2014/369473 ◽

2014 ◽

Vol 2014 ◽

pp. 1-9 ◽

Cited By ~ 1

Author(s):

Narendran Kandaswamy ◽

Nanthini Raveendiran

Keyword(s):

Gel Permeation Chromatography ◽

Inherent Viscosity ◽

Proton Nuclear Magnetic Resonance ◽

Diffusion Method ◽

X Ray Diffraction ◽

Anticancer Activities ◽

Scanning Calorimetry ◽

H Nmr ◽

Agar Disc

Synthesis of random biscoumarin copolyester bearing pendant 3-(trifluoromethyl)styrene was prepared by the reaction of biscoumarin monomer 3 and hydroquinone 5 with azeloyl chloride. The influence of pendant 3-(trifluoromethyl)styrene unit on the properties of copolyester such as inherent viscosity, solubility, and thermal stability was investigated and compared in detail. The inherent viscosity and polydispersity index of the copolyester were found to be 0.15 dL/g and 1.36, respectively. The chemical structure of the copolyester was investigated by Fourier-transform infrared spectroscopy (FTIR) and proton nuclear magnetic resonance (1H-NMR) spectroscopy. The physical properties of copolyester were characterized by thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), gel permeation chromatography (GPC), and X-ray diffraction (XRD) technique. Agar disc diffusion method was employed to study the antimicrobial activity of the random copolyester. In vitro anticancer activity against lung cancer (Hep-2) cell line was also investigated.

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Preparation of a Low Reducing Effect Sulfonated Alkali Lignin and Application as Dye Dispersant

Polymers ◽

10.3390/polym10090982 ◽

2018 ◽

Vol 10 (9) ◽

pp. 982 ◽

Cited By ~ 11

Author(s):

Yanlin Qin ◽

Xuliang Lin ◽

Yaoqin Lu ◽

Siyuan Wu ◽

Dongjie Yang ◽

...

Keyword(s):

Molecular Weight ◽

High Temperatures ◽

Phenolic Hydroxyl ◽

Hydroxyl Groups ◽

Sodium Lignosulfonate ◽

Sulfonic Group ◽

Alkali Lignin ◽

Group Content ◽

Phenolic Hydroxyl Groups ◽

Condensed Lignin

A novel grafting hydroxypropyl sulfonated and blocking condensed lignin (GSBAL) dye dispersant was prepared based on alkali lignin (AL) by sulfonation and etherification reactions. The significant increase in the sulfonic group content and the molecular weight endow GSBAL with excellent dispersity and stability at high temperatures. More importantly, the unfavorable property of the reducing effect of AL was largely reduced since over 80% of the phenolic hydroxyl groups were blocked. The functional azo groups in the dye could be mostly retained. The reducing rate of dye with GSBAL was decreased to 6.54% (25 °C), much lower than 18.62% for sulfomethylated alkali lignin (SAL) and 15.73% for sodium lignosulfonate (NaLS). The dispersity and exhaustion of the dye bath with GSBAL dispersant was significantly improved compared with that of a dye bath with SAL and NaLS.

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Synthesis, Characterization, and In Vitro Antimicrobial and Anticancer Evaluation of Copolyester Bearing 4-Arylidene Curcumin in the Main Chain

International Scholarly Research Notices ◽

10.1155/2014/495927 ◽

2014 ◽

Vol 2014 ◽

pp. 1-6 ◽

Cited By ~ 1

Author(s):

Narendran Kandaswamy ◽

Nanthini Raveendiran

Keyword(s):

Gel Permeation Chromatography ◽

Inherent Viscosity ◽

Proton Nuclear Magnetic Resonance ◽

Diffusion Method ◽

X Ray Diffraction ◽

Scanning Calorimetry ◽

Polymer Backbone ◽

H Nmr ◽

Agar Disc

Synthesis of random copolyester bearing 4-arylidene curcumin M1 in the polymer backbone was prepared by solution polycondensation method. The influence of copolyester bearing 4-arylidene curcumin M1 unit on the properties of copolyester such as inherent viscosity, solubility, and thermal stability was investigated and studied in detail. The inherent viscosity and polydispersity index of the copolyester were found to be 0.19 dL/g and 1.38, respectively. The chemical structure of the copolyester was investigated by Fourier-transform infrared spectroscopy (FTIR) and proton nuclear magnetic resonance (1H-NMR) spectroscopy. The physical properties of copolyester were characterized by thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), gel permeation chromatography (GPC), and X-ray diffraction (XRD) technique. Agar disc diffusion method was employed to study the antimicrobial activity of the random copolyester. In vitro anticancer activity against lung cancer (Hep-2) cell line was investigated.

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The Influence of Laccase Modification on the Adsorption of Lignosulfonate

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.550-553.1266 ◽

2012 ◽

Vol 550-553 ◽

pp. 1266-1269

Author(s):

Hai Feng Zhou ◽

Dong Jie Yang ◽

Meng Xian Bai ◽

Xue Qing Qiu

Keyword(s):

Self Assembly ◽

Gel Permeation Chromatography ◽

Phenolic Hydroxyl ◽

Hydroxyl Groups ◽

Mean Square ◽

Sodium Lignosulfonate ◽

Gel Permeation ◽

Initial Decrease ◽

Assembly Technology ◽

Phenolic Hydroxyl Groups

The ability of commercial laccase to improve the adsorption of sodium lignosulfonate (SL) without any mediator was studied. When SL are modified by laccase, gel permeation chromatography (GPC) shows an initial decrease followed by an extensive increase in molecular weight (Mw). Furthermore, the decrease in Mw is accompanied by an increase in phenolic hydroxyl groups, while the increase in Mw is accompanied by the decrease in phenolic hydroxyl groups. The laccase modification does not affect the content of the sulfonic group. Furthermore, the electrostatic self-assembly technology indicates that the adsorbed amount and the root-mean-square (RMS) of SL/PDAC multilayers increase obviously with the increase of the incubation time, which might be due to the influence of the Mw and the adsorption configuration.

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Study on Mechanism of Action of Catalysts on Liquefaction of Bagasse Alkali Lignin

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.383-390.6145 ◽

2011 ◽

Vol 383-390 ◽

pp. 6145-6150 ◽

Cited By ~ 2

Author(s):

Xin Jin Sui ◽

Shu Bin Wu

Keyword(s):

Mechanism Of Action ◽

Black Liquor ◽

Total Yield ◽

Structural Rearrangement ◽

Hydroxyl Groups ◽

Use Value ◽

Optimal Conditions ◽

Alkali Lignin ◽

H Nmr ◽

Ft Ir

Bagasse alkali lignin is the primary constituent of pulping black liquor. The phenolic products such as phenol, 2,6-dimethoxy-phenol and 2-methoxy-phenol were obtained by catalytic liquefaction from bagasse alkali lignin, with the aim of enhancing its use value. In the investigation, under optimal conditions, using SiO2-Al2O3 or FeS as catalyst, the phenols yield reached 54.10% and 55.18%, respectively. HPLC spectrum showed that the phenolic products of them were different. FT-IR and H-NMR spectrums showed that, using SiO2-Al2O3 as the catalyst, the α-O-4 and β-O-4 ether bonds and C-Cα bonds of lignin units were prone to break, forming 2,6-dimethoxy-phenol, 2-methoxy-phenol and phenol. While FeS action was more difficult, the α-O-4 and β-O-4 ether bonds and Cα-Cβ bonds of lignin units broke down. Then, the introduction of additional hydroxyl groups from glycols consequently increased the final product solubility. At the same time, Cα–C bond of the phenylpropane linkage was broken to produce phenolic chemicals. Third, part of the phenylpropane linkage was prone to break Cα–Cβ bond and structural rearrangement occurred. So the content of 2-methoxy-4-methyl-phenol and the total yield of phenols were high.

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Thermal and Structural Characterization of Two Commercially Available Technical Lignins for High-value Applications

10.26434/chemrxiv.13570790 ◽

2021 ◽

Author(s):

Tanvir Amit ◽

Ranen Roy ◽

Douglas E. Raynie

Keyword(s):

Structural Characterization ◽

Cupric Oxide ◽

Proton Nuclear Magnetic Resonance ◽

Resonance Spectroscopy ◽

Scanning Calorimetry ◽

Alkali Lignin ◽

Structural Modifications ◽

H Nmr ◽

Chemical Pulping ◽

Technical Lignins

Lignin is a complex polyaromatic macromolecule and a potential source of various sustainable materials and feedstock chemicals. To this end, researchers have made some considerable efforts in the high-value applications of lignin, even though there is a limited success so far. This is mainly because the exact structure of native lignin is still virtually unknown due to its highly heterogeneous nature. Besides, technical lignin undergoes unintended structural modifications during the chemical pulping and extraction processes making its final structure even more complicated. Therefore, understanding the lignin structure and its macromolecular characteristics is essential for its proper utilization. In this study, two technical lignins, such as indulin AT and alkali-treated lignin, were investigated for thermal and structural characterization. Various thermal behaviors were studied using thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). Indulin AT was found to be thermally more stable compared to alkali lignin. Structural characterization was performed using attenuated total reflectance-Fourier transform infrared (ATR-FTIR) spectroscopy and proton nuclear magnetic resonance spectroscopy (1H NMR). Cupric oxide oxidation was utilized to selectively degrade the lignin into its monomers (H/G/S-moieties), which were identified with GC-MS. The results suggested that the selected lignins are mainly composed of G-type monomers. The detailed characterization studies also revealed some minor structural differences between the two lignins due to their respective delignification process. Indulin AT underwent higher structural modifications due to the harsher delignification process and hinted to show more recalcitrance toward depolymerization than alkali lignin.

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Thermal and Structural Characterization of Two Commercially Available Technical Lignins for High-value Applications

10.26434/chemrxiv.13570790.v1 ◽

2021 ◽

Author(s):

Tanvir Amit ◽

Ranen Roy ◽

Douglas E. Raynie

Keyword(s):

Structural Characterization ◽

Cupric Oxide ◽

Proton Nuclear Magnetic Resonance ◽

Resonance Spectroscopy ◽

Scanning Calorimetry ◽

Alkali Lignin ◽

Structural Modifications ◽

H Nmr ◽

Chemical Pulping ◽

Technical Lignins

Lignin is a complex polyaromatic macromolecule and a potential source of various sustainable materials and feedstock chemicals. To this end, researchers have made some considerable efforts in the high-value applications of lignin, even though there is a limited success so far. This is mainly because the exact structure of native lignin is still virtually unknown due to its highly heterogeneous nature. Besides, technical lignin undergoes unintended structural modifications during the chemical pulping and extraction processes making its final structure even more complicated. Therefore, understanding the lignin structure and its macromolecular characteristics is essential for its proper utilization. In this study, two technical lignins, such as indulin AT and alkali-treated lignin, were investigated for thermal and structural characterization. Various thermal behaviors were studied using thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). Indulin AT was found to be thermally more stable compared to alkali lignin. Structural characterization was performed using attenuated total reflectance-Fourier transform infrared (ATR-FTIR) spectroscopy and proton nuclear magnetic resonance spectroscopy (1H NMR). Cupric oxide oxidation was utilized to selectively degrade the lignin into its monomers (H/G/S-moieties), which were identified with GC-MS. The results suggested that the selected lignins are mainly composed of G-type monomers. The detailed characterization studies also revealed some minor structural differences between the two lignins due to their respective delignification process. Indulin AT underwent higher structural modifications due to the harsher delignification process and hinted to show more recalcitrance toward depolymerization than alkali lignin.

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