scholarly journals Valorization of Lignin as a Sustainable Component of Structural Materials and Composites: Advances from 2011 to 2019

2020 ◽  
Vol 12 (2) ◽  
pp. 734 ◽  
Author(s):  
Menisha S. Karunarathna ◽  
Rhett C. Smith
Keyword(s):  
Chemical Modification ◽  
Functional Groups ◽  
Carbon Fibers ◽  
Network Structure ◽  
Phenol Formaldehyde ◽  
Construction Materials ◽  
Structural Elements ◽  
Automotive Components ◽  
Future Developments ◽  
Technical Issues

Lignin is the most abundant aromatic biopolymer and is the sustainable feedstock most likely to supplant petroleum-derived aromatics and downstream products. Rich in functional groups, lignin is largely peerless in its potential for chemical modification towards attaining target properties. Lignin’s crosslinked network structure can be exploited in composites to endow them with remarkable strength, as exemplified in timber and other structural elements of plants. Yet lignin may also be depolymerized, modified, or blended with other polymers. This review focuses on substituting petrochemicals with lignin derivatives, with a particular focus on applications more significant in terms of potential commercialization volume, including polyurethane, phenol-formaldehyde resins, lignin-based carbon fibers, and emergent melt-processable waste-derived materials. This review will illuminate advances from the last eight years in the prospective utilization of such lignin-derived products in a range of application such as adhesives, plastics, automotive components, construction materials, and composites. Particular technical issues associated with lignin processing and emerging alternatives for future developments are discussed.

Surface and Composite Interface of Carbon Fiber Modified by Grafting of Diethanolamine

2009 ◽  
Vol 79-82 ◽  
pp. 497-500 ◽  
Author(s):  
Lei Chen ◽  
Zhi Wei Xu ◽  
Jia Lu Li ◽  
Xiao Qing Wu ◽  
Li Chen
Keyword(s):  
Shear Strength ◽  
Carbon Fiber ◽  
Functional Groups ◽  
Carbon Fibers ◽  
Irradiation Dose ◽  
Interlaminar Shear Strength ◽  
Epoxy Composites ◽  
Composite Interface ◽  
Γ Ray ◽  
Interlaminar Shear

The γ-ray co-irradiation method was employed to study the effect of diethanolamine modification on the surface of carbon fiber (CF) and the interfacial properties of CF/epoxy composites. Compared with the original carbon fiber, the surface of modified fibers became rougher. The amount of oxygen-containing functional groups was increased and the nitrogen element was detected after irradiation grafting. The interlaminar shear strength (ILSS) of composites reinforced by carbon fibers irradiated in diethanolamine solution was increased and then decreased as the irradiation dose increased. The ILSS of CF/epoxy composites was enhanced by 16.1% at 200kGy dose, compared with that of untreated one. The γ-ray irradiation grafting is expected to be a promising method for the industrialized modification of carbon fibers.

Study on the Composites of Phenol Formaldehyde Resin/Graphite Reinforced by Milled Carbon Fibers for Bipolar Plates

2010 ◽  
Vol 156-157 ◽  
pp. 1090-1096
Author(s):  
Wei Qiang Wang ◽  
Ai Ju Li ◽  
Ming Ming You ◽  
Bin Xia
Keyword(s):  
Electrical Conductivity ◽  
Liquid Phase ◽  
Flexural Strength ◽  
Carbon Fibers ◽  
Phenol Formaldehyde ◽  
Resin Content ◽  
Liquid Phase Oxidation ◽  
Bipolar Plates ◽  
Air Oxidation ◽  
Phase Oxidation

Composites of phenol formaldehyde (PF) resin/graphite reinforced by milled carbon fibers (MCFs) for bipolar plates are obtained by hot compression molding. The raw materials of the MCF particles, PF resin powder and graphite powder are simply dry powder ball milled and mixed. The effects of PF resin content and the content, granularity and surface treatment methods, such as air oxidation and Fenton/ultraviolet (UV) liquid-phase oxidation of MCFs on the electrical conductivity and flexural strength of the composites are measured by methods of four-point probe technique and three point flexural test, and the fracture patterns of the composites are analyzed by scanning electron microscope (SEM). The results indicate that the electrical conductivity decreases and flexural strength increases with the increase of PF resin content. Especially, the values of electrical conductivity and flexural strength can reach 165.28 S.cm-1 and 55.11MPa respectively when the PF resin content was 17% in weight. The properties of composites reinforced by air oxidation treated MCFs are better than those by liquid-phase oxidation treated one. The electrical conductivity and flexural strength of the composites are 208.12S.cm-1 and 57.44 MPa when they reinforced by 5% MCFs which treated by air oxidation at 450 . Compared with the nonreinfoced composites, the properties of reinforced composites increase 25.92% in electrical conductivity and 4.23% in flexural strength.

A Study of Surface Modification on Adsorption Behaviors of Nanoporous Carbon

2007 ◽  
Vol 119 ◽  
pp. 211-214 ◽  
Author(s):  
Byeoung Ku Kim ◽  
Young Seak Lee ◽  
Seung Kon Ryu ◽  
Byung Joo Kim ◽  
Soo Jin Park
Keyword(s):  
Nitric Acid ◽  
Functional Groups ◽  
Carbon Fibers ◽  
Acid Treatment ◽  
Surface Acidity ◽  
Activated Carbon Fibers ◽  
Adsorption Behaviors ◽  
Toxic Gases ◽  
Adsorption Amount ◽  
Polar Functional Groups

In this work, to introduce polar functional groups on carbon surfaces, activated carbon fibers (ACFs) were treated by nitric acid in order to enhance the adsorption capacity of propylamine which was one of toxic gases in cigarette smoke. It was found that the polar functional groups were predominantly increased up to 2.0 M of nitric acid, resulting in the increase of total surface acidity. It was found that the adsorption amount of propylamine of the modified ACFs was increased around 17% after a nitric acid treatment. From the XPS results, it was observed that propylamine was reacted with strong or weak polar (acidic) groups, such as COOH, -COO or OH existed on the ACF surfaces.

scholarly journals Using a Core Scientific Metadata Model in Large-Scale Facilities

2010 ◽  
Vol 5 (1) ◽  
pp. 106-118 ◽  
Author(s):  
Brian Matthews ◽  
Shoaib Sufi ◽  
Damian Flannery ◽  
Laurent Lerusse ◽  
Tom Griffin ◽  
...  
Keyword(s):  
Large Scale ◽  
Materials Science ◽  
Production Quality ◽  
Scientific Study ◽  
Quality Data ◽  
Structural Elements ◽  
Metadata Model ◽  
The Core ◽  
Future Developments ◽  
The Relationship

In this paper, we present the Core Scientific Metadata Model (CSMD), a model for the representation of scientific study metadata developed within the Science & Technology Facilities Council (STFC) to represent the data generated from scientific facilities. The model has been developed to allow management of and access to the data resources of the facilities in a uniform way, although we believe that the model has wider application, especially in areas of “structural science” such as chemistry, materials science and earth sciences. We give some motivations behind the development of the model, and an overview of its major structural elements, centred on the notion of a scientific study formed by a collection of specific investigations. We give some details of the model, with the description of each investigation associated with a particular experiment on a sample generating data, and the associated data holdings are then mapped to the investigation with the appropriate parameters. We then go on to discuss the instantiation of the metadata model within a production quality data management infrastructure, the Information CATalogue (ICAT), which has been developed within STFC for use in large-scale photon and neutron sources. Finally, we give an overview of the relationship between CSMD, and other initiatives, and give some directions for future developments.    

Preparation of carbon fibers from biomass-based phenol-formaldehyde resin

2005 ◽  
Vol 40 (2) ◽  
pp. 335-339 ◽  
Author(s):  
C. Yoshida ◽  
K. Okabe ◽  
T. Yao ◽  
N. Shiraishi ◽  
A. Oya
Keyword(s):  
Carbon Fibers ◽  
Phenol Formaldehyde ◽  
Phenol Formaldehyde Resin ◽  
Formaldehyde Resin

scholarly journals Preparation and Characterization of Chemically-Modified Biomaterials and Their Application as Adsorbents of Penicillin G

2018 ◽  
Vol 1 (1) ◽  
pp. 114-124 ◽  
Author(s):  
Jesie Silva ◽  
Lizebel Morante ◽  
Tesfamichael Demeke ◽  
Jacqueline Baah-Twum ◽  
Abel Navarro
Keyword(s):  
Chemical Modification ◽  
Functional Groups ◽  
Negative Impact ◽  
Ph Dependence ◽  
Sem Analysis ◽  
Penicillin G ◽  
Tea Leaves ◽  
Reaction Conditions ◽  
Spent Tea Leaves

The prevalence of antibiotics in water creates microbial resistance and has a negative impact on the ecosystem. Biomaterials such as spent tea leaves are rich in functional groups and are suitable for chemical modification for diverse applications. This research proposes the use of spent tea leaves of chamomile (CM), green tea (GT), and peppermint (PM) as structural scaffolds for the incorporation of carboxyl, sulfonyl, and thiol groups to improve the adsorption of Penicillin G (Pe). Adsorbents characterization reported a higher number of acidic functional groups, mainly in thiolated products. Scanning electron microscopy (SEM) analysis showed changes on the surfaces of the adsorbents due to reaction conditions, with a stronger effect on thiolated and sulfonated adsorbents. Elemental analysis by Energy dispersive X-ray spectrophotometry (EDS) corroborated the chemical modification by the presence of sulfur atoms and the increase in oxygen/carbon ratios. Batch experiments at different pH shows a strong pH-dependence with a high adsorption at pH 8 for all the adsorbents. The adsorption follows the trend CMs > GTs > PMs. Thiolation and sulfonation reported higher adsorptions, which is most likely due to the sulfur bridge formation, reaching adsorption percentages of 25%. These results create a new mindset in the use of spent tea leaves and their chemical modifications for the bioremediation of antibiotics.

scholarly journals FTIR analysis of chemical changes in wood induced by steaming and longitudinal compression

Cellulose ◽  
2020 ◽  
Vol 27 (12) ◽  
pp. 6811-6829 ◽  
Author(s):  
Mátyás Báder ◽  
Róbert Németh ◽  
Jakub Sandak ◽  
Anna Sandak
Keyword(s):  
Functional Groups ◽  
Cell Walls ◽  
Beech Wood ◽  
Industrial Applications ◽  
Structural Elements ◽  
Longitudinal Compression ◽  
Chemical Mechanisms ◽  
Modification Process ◽  
Physical Chemical ◽  
Detailed Interpretation

Abstract Pleating is an optimal way to increase bendability of wood used in diverse industrial applications. It results in the excessive buckling of cell walls and modifications of constitutive polymers. However, thoughtful understanding of the physical–chemical mechanisms of that modification process is very limited. The main purpose of the present study was to identify changes in functional groups of wood polymers induced by longitudinal compression. Four types of wood samples prepared from beech and sessile oak (untreated, steamed, longitudinally compressed and fixated for 1 min as well as longitudinally compressed and fixated for 18 h) were assessed by infrared spectroscopy. The spectra interpretation revealed that changes can be observed in hydroxyl as well as in carbon–oxygen single and carbon-hydrogen functional groups of polysaccharides and lignin. Beech wood seems to be more susceptible to investigated modification processes as compared to oak. Detailed interpretation of infrared spectra allows identification of changes in the hygroscopicity of wood as well as alterations in the linkage between structural elements in the polymer matrix of wood induced by the applied treatments. Graphic Abstract

scholarly journals Effects of Chemical Modification on the Mechanical Properties of Calotropis Gigantea Fiber-reinforced Phenol Formaldehyde Biocomposites

2020 ◽  
Vol 26 (3) ◽  
pp. 295-299
Author(s):  
Sekar SANJEEVI ◽  
Athijayamani AYYANAR ◽  
Ramanathan KALIMUTHU ◽  
Sidhardhan SUSAIYAPPAN
Keyword(s):  
Mechanical Properties ◽  
Chemical Modification ◽  
Phenol Formaldehyde ◽  
Fiber Composites ◽  
Fiber Content ◽  
The Other ◽  
Fiber Reinforced ◽  
Calotropis Gigantea ◽  
Chemical Treatments ◽  
Treated Fiber

In this paper, the effects of three different chemical treatments on the mechanical properties of Phenol Formaldehyde (PF) composites reinforced with the Calotropis Gigantea Fibers (CGFs) were investigated based on the fiber content of the fibers. Composites were prepared by the untreated and treated fibers using the hand lay up technique and their mechanical properties were evaluated and compared. The results revealed that the composites show the greater mechanical properties at 40 wt.% for the untreated condition. Composites prepared with alkali treated fibers show the better mechanical properties as compared with the other treated fiber composites.

scholarly journals A facile approach for grafting bi-functional groups terminated branched polyphosphazene on carbon fibers

2020 ◽  
Vol 14 (10) ◽  
pp. 962-969
Author(s):  
Z. J. He ◽  
J. H. Liu ◽  
S. H. Liu ◽  
X. Q. Zhang ◽  
C. H. Lei
Keyword(s):  
Functional Groups ◽  
Carbon Fibers
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