Stabilization of polyacrylonitrile nanofiber mats obtained by needleless electrospinning using dimethyl sulfoxide as solvent

Polyacrylonitrile can be used as a base material for thermochemical conversion into carbon. Especially nanofiber mats, produced by electrospinning, are of interest to create carbon nanofibers. Optimal stabilization and carbonization parameters, however, strongly depend on the spatial features of the original material. While differences between nano- and microfibers are well known, this paper shows that depending on the electrospinning method and the solvent used, considerable differences between various nanofiber mats have to be taken into account for the optimization of the stabilization conditions. Here, we examine for the first time polyacrylonitrile nanofiber mats, electrospun with wire electrospinning from the low-toxic dimethyl sulfoxide as a solvent, instead of the typically used needle electrospinning from the toxic dimethylformamide. Additionally, we used inexpensive polyacrylonitrile from knitting yarn instead of highly specialized material, tailored for carbonization. Our results show that by carefully controlling the maximum stabilization temperature and especially the heating rate, fully stabilized polyacrylonitrile fibers without undesired interconnections can be created as precursors for carbonization.

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Stabilization of Electrospun PAN/Gelatin Nanofiber Mats for Carbonization

Journal of Nanomaterials ◽

10.1155/2018/6131085 ◽

2018 ◽

Vol 2018 ◽

pp. 1-12 ◽

Cited By ~ 12

Author(s):

Lilia Sabantina ◽

Daria Wehlage ◽

Michaela Klöcker ◽

Al Mamun ◽

Timo Grothe ◽

...

Keyword(s):

Chemical Properties ◽

Base Material ◽

Industrial Processes ◽

Fiber Morphology ◽

Heating Rates ◽

Stabilization Temperature ◽

Nanofiber Mats ◽

The Impact ◽

Pan Nanofiber ◽

Highly Porous

Due to their electrical and mechanical properties, carbon nanofibers are of large interest for diverse applications, from batteries to solar cells to filters. They can be produced by electrospinning polyacrylonitrile (PAN), stabilizing the gained nanofiber mats, and afterwards, carbonizing them in inert gas. The electrospun base material and the stabilization process are crucial for the results of the carbonization process, defining the whole fiber morphology. While blending PAN with gelatin to gain highly porous nanofibers has been reported a few times in the literature, no attempts have been made yet to stabilize and carbonize these fibers. This paper reports on the first tests of stabilizing PAN/gelatin nanofibers, depicting the impact of different stabilization temperatures and heating rates on the chemical properties as well as the morphologies of the resulting nanofiber mats. Similar to stabilization of pure PAN, a stabilization temperature of 280°C seems suitable, while the heating rate does not significantly influence the chemical properties. Compared to stabilization of pure PAN nanofiber mats, approximately doubled heating rates can be used for PAN/gelatin blends without creating undesired conglutinations, making this base material more suitable for industrial processes.

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Access to 2-Arylquinazolines via Catabolism/Reconstruction of Amino Acids with Insertion of Dimethyl Sulfoxide

Chemical Communications ◽

10.1039/d1cc00623a ◽

2021 ◽

Author(s):

Jin-Tian Ma ◽

Li-Sheng Wang ◽

Zhi Chai ◽

Xin-Feng Chen ◽

Bo-Cheng Tang ◽

...

Keyword(s):

Amino Acids ◽

Amino Acid ◽

Dimethyl Sulfoxide ◽

Nitrogen Source ◽

Carbon And Nitrogen ◽

First Time

Quinazoline skeletons are synthesized by amino acids catabolism/reconstruction combined with dimethyl sulfoxide insertion/cyclization for the first time. The amino acid acts as a carbon and nitrogen source through HI-mediated catabolism...

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Fabrication and Characterization of Lignin/Dendrimer Electrospun Blended Fiber Mats

Molecules ◽

10.3390/molecules26030518 ◽

2021 ◽

Vol 26 (3) ◽

pp. 518

Author(s):

Somaye Akbari ◽

Addie Bahi ◽

Ali Farahani ◽

Abbas S. Milani ◽

Frank Ko

Keyword(s):

Thermal Characteristics ◽

Dendritic Polymers ◽

Amino Groups ◽

Fiber Mats ◽

Potential Applications ◽

Solution Electrospinning ◽

Nanofiber Mats ◽

Softwood Kraft Lignin ◽

First Time

Blending lignin as the second most abundant polymer in Nature with nanostructured compounds such as dendritic polymers can not only add value to lignin, but also increase its application in various fields. In this study, softwood Kraft lignin/polyamidoamine dendritic polymer (PAMAM) blends were fabricated by the solution electrospinning to produce bead-free nanofiber mats for the first time. The mats were characterized through scanning electron microscopy, Fourier transform infrared (FTIR) spectroscopy, zeta potential, and thermogravimetry analyses. The chemical intermolecular interactions between the lignin functional groups and abundant amino groups in the PAMAM were verified by FTIR and viscosity measurements. These interactions proved to enhance the mechanical and thermal characteristics of the lignin/PAMAM mats, suggesting their potential applications e.g. in membranes, filtration, controlled release drug delivery, among others.

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Facile synthesis of luminescent and amorphous La2O3–ZrO2:Eu3+ nanofibrous membranes with robust softness

Nanoscale ◽

10.1039/c5nr02173a ◽

2015 ◽

Vol 7 (34) ◽

pp. 14248-14253 ◽

Cited By ~ 13

Author(s):

Weidong Han ◽

Bin Ding ◽

Mira Park ◽

Fuhai Cui ◽

Zafar Khan Ghouri ◽

...

Keyword(s):

Facile Synthesis ◽

Electrospinning Method ◽

Nanofibrous Membranes ◽

First Time

Luminescent and amorphous La2O3–ZrO2:Eu3+ nanofibrous membranes with robust softness were prepared for the first time by a facile electrospinning method.

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Synopsis and typification of the names published by Antonio Bertoloni in Florula Guatimalensis and in preceding publications

Phytotaxa ◽

10.11646/phytotaxa.420.3.1 ◽

2019 ◽

Vol 420 (3) ◽

pp. 199-223

Author(s):

RICCARDO M. BALDINI ◽

ANA LUCRECIA MACVEAN ◽

GIOVANNI CRISTOFOLINI ◽

THOMAS F. DANIEL ◽

ANNALISA MANAGLIA ◽

...

Keyword(s):

New Taxa ◽

Original Material ◽

New Combinations ◽

Original Publication ◽

First Time ◽

Original Drawings

Bertoloni published Florula guatimalensis in 1840, which is commonly cited as the original publication. However, our findings show that previous publications of Alessandrini of 1838 and 1840 include the original descriptions by Bertoloni which predate Florula guatimalensis. Among the 60 new taxa authored by Bertoloni, 26 were published in 1838 and 34 in 1840 by Alessandrini. Additionally, original drawings were discovered inside an old copy of Bertoloni’s Florula guatimalensis. Also a comparison between the original material from Bertoloni’s herbarium and his original drawings is here reported for the first time. The collection of Guatemalan plants studied by Antonio Bertoloni preserved at BOLO was analysed and is here discussed. The new combinations Odontonema corymbulosum and Lamourouxia barbata are proposed. A neotype for Aristolochia podocarpa and an epitype for Philadelphus myrtoides are here designated.

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Fossil flora of Middle Jurassic Grojec clays (southern Poland). Raciborski’s original material reinvestigated and supplemented. I. Sphenophytes

Acta Palaeobotanica ◽

10.1515/acpa-2015-0013 ◽

2015 ◽

Vol 55 (2) ◽

pp. 149-181

Author(s):

Agata Jarzynka ◽

Grzegorz Pacyna

Keyword(s):

New Species ◽

Middle Jurassic ◽

Fossil Flora ◽

Vascular Bundles ◽

Original Material ◽

Type Specimens ◽

Southern Poland ◽

The Poor ◽

The Common ◽

First Time

AbstractSphenopsid remains from Grojec clays (Grojec, Poręba, Mirów) collected and described by Raciborski in 1894 are re-examined for the first time and supplemented by Raciborski’s unpublished material housed at the Jagiellonian University (Institute of Botany) and by Stur’s preliminarily described material stored at the Geological Survey of Austria. Three species of Equisetum created by Raciborski (Equisetum renaulti, E. remotum, E. blandum) are now attributed to the common Jurassic species Equisetites lateralis, and the earlierundescribed Equisetites cf. columnaris is recognised. The occurrence of Neocalamites lehmannianus (originally described by Raciborski as Schizoneura hoerensis) has been confirmed from Grojec. The material that Raciborski referred to this species seems to be heterogeneous, and some specimens are now removed to the new proposed species Neocalamites grojecensis Jarzynka et Pacyna sp. nov. The new species is diagnosed by the following features: only a few prominent ribs present on shoot, leaf scars relatively large and ellipsoidal, numerous free leaves, vascular bundles alternate at node. Possibly the new species derives from Neocalamites lehmannianus or at least is closely related to it. Part of the poorly preserved remains can be determined only as Neocalamites sp. Another species created by Raciborski, Phyllotheca (?) leptoderma, is based on poorly preserved type specimens. Some of the unpublished specimens stored at the Jagiellonian University (Institute of Botany) correspond to Raciborski’s description, but considering the poor preservation of the original material and the not very realistic published illustrations of this species, they rather should be regarded as indeterminate cortical fragments of Neocalamites lehmannianus and/or badly preserved external cortical surfaces of the new species Neocalamites grojecensis. Phyllotheca (?) leptoderma should be considered a nomen dubium.

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The first record of Iris setosa (Iridaceae) in Europe

Phytotaxa ◽

10.11646/phytotaxa.437.1.4 ◽

2020 ◽

Vol 437 (1) ◽

pp. 32-38

Author(s):

EUGENY V. BOLTENKOV ◽

MARIJA Y. MENSHAKOVA ◽

RAMZIYA I. GAINANOVA ◽

ZINAIDA Y. RUMJANTSEVA

Keyword(s):

North America ◽

Russian Federation ◽

Northeast Asia ◽

First Record ◽

Morphological Description ◽

Murmansk Oblast ◽

Original Material ◽

Detection And Identification ◽

First Time

Iris setosa is one of the widespread Iris species in Northeast Asia and North America. In 2018, it was found for the first time in Europe, on Kildin Island (Murmansk Oblast, Russian Federation). The presence of this plant on the island and its disjunct range are discussed. To facilitate further detection and identification, a general morphological description, information about the original material of the name I. setosa, and supporting illustrations are here provided.

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Enhanced stability of PVA electrospun fibers in water by adding cellulose nanocrystals

Holzforschung ◽

10.1515/hf-2014-0277 ◽

2015 ◽

Vol 69 (6) ◽

pp. 737-743 ◽

Cited By ~ 10

Author(s):

Anna Sutka ◽

Andris Sutka ◽

Sergej Gaidukov ◽

Martin Timusk ◽

Janis Gravitis ◽

...

Keyword(s):

Aqueous Medium ◽

Steam Explosion ◽

Thermal Studies ◽

Poly Vinyl Alcohol ◽

Electrospun Fibers ◽

Alkaline Extraction ◽

Experimental Findings ◽

Nanofiber Mats ◽

First Time ◽

Enhanced Stability

Abstract The solubility of electrospun poly(vinyl alcohol) nanofiber mats (PVAES-NFM) is strongly influenced by loading with nanocellulose (NC). The NC was derived from hemp shives obtained by steam explosion autohydrolysis followed by water and alkaline extraction, ball milling, and ultrasonication treatments. It was demonstrated for the first time that PVAES-NFM does not disintegrate in aqueous medium after simple adding of NC without any additional chemical or physical modification (PVAES-NFMNC). The structural and thermal studies on PVAES-NFMNC indicated that enhanced stability in aqueous medium can be explained by interactions between surface groups of NC and PVA macromolecules as well as by reinforcing the effect of NCs. The experimental findings could be important for filtration applications in environments with high relative humidity.

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Taxonomic notes on hexapogon irises (Iridaceae)

Phytotaxa ◽

10.11646/phytotaxa.328.3.8 ◽

2017 ◽

Vol 328 (3) ◽

pp. 291

Author(s):

EUGENY V. BOLTENKOV

Keyword(s):

Relevant Literature ◽

Herbarium Specimens ◽

Original Material ◽

Central Asian ◽

Desert Regions ◽

First Time ◽

Central Asian Republics

The taxonomic notes in this article are based on the result of an analysis of the protologues, relevant literature, and a study of herbarium specimens of Iris sect. Hexapogon. This section comprises species with bearded claw in both outer and inner segments of perianth. These are relatively poorly known psammophytes occurring mostly in the desert and semi-desert regions of some of the former Soviet Central Asian republics, as well as in Iran, Afghanistan and Pakistan (Baluchistan). It is now generally accepted that I. sect. Hexapogon comprises two species, I. falcifolia and I. longiscapa. The present study has shown that this section contains only I. longiscapa. The name I. falcifolia is for the first time reduced to a synonym of I. longiscapa. A neotype for the name I. longiscapa and lectotypes for the names I. falcifolia and I. filifolia are designated. Notes are provided on the original material for all the three considered names.

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Production and characterization of boron nitride-doped nanofiber mats created through electrospinning

Journal of Industrial Textiles ◽

10.1177/1528083716657814 ◽

2016 ◽

Vol 47 (6) ◽

pp. 993-1005 ◽

Cited By ~ 1

Author(s):

Yasemin Cakmak ◽

M Fatih Canbolat ◽

Enes Cakmak ◽

Mehmet Dayik

Keyword(s):

Thermal Stability ◽

Fourier Transform ◽

Infrared Spectroscopy ◽

Thermogravimetric Analysis ◽

Boron Nitride ◽

Fourier Transform Infrared Spectroscopy ◽

Fourier Transform Infrared ◽

Electrospinning Method ◽

The Fourier Transform ◽

Nanofiber Mats

The aim of this study was to produce advanced nanofiber mats by adding boron nitride to poly (ɛ-caprolactone) polymer using an electrospinning method and to characterize the resultant structures. Pure poly (ɛ-caprolactone) nanofiber mats and boron nitride-doped nanofiber mats prepared at different concentrations were compared. The morphological structures of the nanofiber mats were examined under a scanning electron microscope, spectroscopic analyses were conducted using Fourier transform infrared spectroscopy, and thermal stability was analyzed using a thermogravimetric analysis method. Successful electrospinning of boron nitride-doped nanofibers at lower voltages was achieved. The thermogravimetric analysis test found that the thermal stability of boron nitride-doped nanofiber mats is higher than that of pure nanofibers, which suggests that the produced composite material could be preferable in applications involving insulation and high temperature. On the other hand, the Fourier transform infrared spectroscopy results indicated that no chemical reaction occurred between boron nitride and the poly (ɛ-caprolactone) nanofibers.

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