Molecular weight distribution and functional group profiles of TEMPO-oxidized lyocell fibers

Milanović, Jovana; Schiehser, Sonja; Milanovic, Predrag; Potthast, Antje; Kostić, Mirjana

doi:10.1016/j.carbpol.2013.06.033

Cited by 19 publications

(9 citation statements)

References 23 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…21 XRD analysis. 22 All these observations are consistent with previous studies of SEM and XRD reported in this study. 2 shows the XRD spectra of MCC irradiated with different absorbed doses from 100 kGy to 1400 kGy.…”

Section: Resultssupporting

confidence: 93%

Insights into the effects of γ-irradiation on the microstructure, thermal stability and irradiation-derived degradation components of microcrystalline cellulose (MCC)

Liu

Chen

et al. 2015

RSC Adv.

View full text Add to dashboard Cite

It has been demonstrated that radiation pretreatment can cause a significant breakdown of the stubborn cellulose structure, which will increase the accessibility of cellulose and enhance enzyme hydrolysis in bio-fuel processes. In this study, using microcrystalline cellulose (MCC) as a model substrate, the impacts of irradiation dose on the microstructure, thermal stability and irradiated-degradation components of cellulose under 60 Co g-irradiation (0-1400 kGy) was comprehensively investigated. FT-IR, EPR and NMR analyses show that irradiation destroys the glycosidic bond and inter-and intramolecular hydrogen bond of cellulose, resulting in the generation of reductive carbonyl groups and free radicals. SEM, XRD and GPC analyses confirm that irradiation can damage the crystalline microstructure and surface morphology of MCC, which reduces its degree of polymerization from 183 045 kDa to 4413 kDa. TGA and DGA curves indicate that the activated energy (E a ) and thermal stability of treated MCC decrease with the increasing irradiation dose. Ion chromatography (IC) analysis demonstrates that there exist fermentation sugars such as glucose (10.73 mg g À1 ), xylose (1.58 mg g À1 ), arabinose (0.46 mg g À1 ), fructose (4.31 mg g À1 ), and cellobiose (1.90 mg g À1 ) as well as low amounts of glucuronic acid (0.35 mg g À1 ) and galacturonic acid (1.46 mg g À1 ) in the irradiation-derived degradation components. Therefore, the findings in this study suggest that g-irradiation processing is an environment-friendly, promising and effective approach to treat lignocellulose biomass.

show abstract

Section: Resultssupporting

confidence: 93%

Insights into the effects of γ-irradiation on the microstructure, thermal stability and irradiation-derived degradation components of microcrystalline cellulose (MCC)

Liu

Chen

et al. 2015

RSC Adv.

View full text Add to dashboard Cite

show abstract

“…The change of polydispersity indexes indicated that irradiation pretreatment disrupted the hemicellulose molecules into homogenization. The average Mw of hemicellulose decreased from 21,313 to 9492 Da when hemicellulose was pretreated at 1200 kGy irradiation dose in comparison with un-irradiated sample, which was probably attributed to irradiationmediated oxidation degradation leading to chain scission [19]. Figure 2 shows the FT-IR spectra of the non-irradiated and irradiated hemicellulose with different absorbed doses.…”

Section: Gpc Analysismentioning

confidence: 94%

“…First, the characteristic peak of around 1715 cm -1 ascribed to the carbonyl groups (C=O stretching vibration) is started to generate at 400 kGy, and the intensity of this peak increases gradually with the further increasing absorbed dose up to 1200 kGy. The probable explanation is probably ascribed to the fact that irradiation will cause the formation of carbonyl and carboxyl groups due to oxidative degradation of hemicellulose in the presence of oxygen [19]. Second, the intensity of band at 901 cm -1 , b-glycosidic linkage between the sugar units in hemicelluloses, increases gradually with the increasing absorbed doses from 200 to 400 kGy.…”

Section: Ft-ir Analysismentioning

confidence: 98%

Structure, Morphology, Thermostability and Irradiation-Mediated Degradation Fractions of Hemicellulose Treated with γ-Irradiation

Chen

Wang

et al. 2016

Waste Biomass Valor

View full text Add to dashboard Cite

To elucidate the physicochemical properties and degradation mechanism of hemicellulose treated with irradiation doses (from 0 to 1200 kGy), a set of experiments on hemicellulose morphology, structure, molecular weight, free radicals, thermal stability, and irradiation mediated fractions was performed. Fourier transforms infrared spectroscopy and nuclear magnetic resonance analyses show that irradiation destroys the inter-and intra-molecular hydrogen bonds of hemicellulose leading to the generation of reductive carbonyl group. Scanning electron microscope, electron paramagnetic resonance and gel permeation chromatography measurements further confirm that the damage degree of hemicellulose structure and morphology surface in dependence on irradiation doses. Thermogravimetry/differential thermogravimetry analyses indicate that the activated energy and thermal stability of irradiated hemicellulose decrease with the increasing of absorbed dose. Irradiation mediated degradation compounds analyses by ion chromatography reveal that xylose (7.64 ± 0.92 mg g -1 ), and arabionose (3.58 ± 0.08 mg g -1 ) and cellubiose (0.27 ± 0.00 mg g -1 ) are observed at 1200 kGy. Amount of glucuronic acid (3.61 ± 0.02 mg g -1 ) and galacturonic acid (7.44 ± 0.38 mg g -1 ), which are respectively derived from glucose and galactose, are also obtained in the water soluble irradiation mediated degradation fraction. These data provide a basis support on a full utilization of hemicellulose after c-irradiation pretreatment.

show abstract

“…In combination with multi-detector gel permeation chromatography (GPC), the method provides profiles of carboxyl groups along the molecular weight distribution. Introduced roughly a decade ago (Bohrn et al 2006), this approach has become widely used in cellulose analysis, and recognized as the ''FDAM method'' (Milanovic et al 2013;Oeztuerk et al 2009;Potthast et al 2006;Tot et al 2009). The studied sizing agents ASA and MSOHO somehow represent two ''unlike twins'', they are rather similar with regard to sizing behavior and reactivity, but belong to two different realms regarding their origins and production.…”

Section: Resultsmentioning

confidence: 98%

Novel paper sizing agents based on renewables. Part 8: on the binding behavior of reactive sizing agents—the question of covalent versus adsorptive binding

et al. 2015

Self Cite

View full text Add to dashboard Cite

The binding mechanisms of two reactive sizing agents, alkenyl succinic anhydride (ASA) and maleated sunflower oil high-oleic (MSOHO), with cellulose were studied. While ASA is produced from olefins out of fossil resources, MSOHO is a green sizing agent based on renewable plant materials. In contrast to common assumptions, that ASA is mostly covalently bound to cellulose, this study showed the largest part of ASA to be bound only by physisorption and only a rather small fraction, typically about 0.5 %, to be covalently attached by ester bonds. In the case of MSOHO, the covalent binding was only slightly higher, with about 3 % of the total amount being covalently linked. In both cases, covalently bound sizing agents were found to be almost uniformly distributed over the whole DP range of the cellulose as seen by carboxyl-selective fluorescence labeling in combination with size exclusion chromatography (''FDAM method'').

show abstract

Molecular weight distribution and functional group profiles of TEMPO-oxidized lyocell fibers

Cited by 19 publications

References 23 publications

Insights into the effects of γ-irradiation on the microstructure, thermal stability and irradiation-derived degradation components of microcrystalline cellulose (MCC)

Insights into the effects of γ-irradiation on the microstructure, thermal stability and irradiation-derived degradation components of microcrystalline cellulose (MCC)

Structure, Morphology, Thermostability and Irradiation-Mediated Degradation Fractions of Hemicellulose Treated with γ-Irradiation

Novel paper sizing agents based on renewables. Part 8: on the binding behavior of reactive sizing agents—the question of covalent versus adsorptive binding

Contact Info

Product

Resources

About