scholarly journals Recent Advances in the Application of Functionalized Lignin in Value-Added Polymeric Materials

Polymers ◽  
2020 ◽  
Vol 12 (10) ◽  
pp. 2277 ◽  
Author(s):  
Yun-Yan Wang ◽  
Xianzhi Meng ◽  
Yunqiao Pu ◽  
Arthur J. Ragauskas
Keyword(s):  
Carbon Fiber ◽  
Phenol Formaldehyde ◽  
Low Cost ◽  
Value Added ◽  
Polymeric Materials ◽  
Intermolecular Forces ◽  
Native Form ◽  
Thermoset Resins ◽  
Soda Lignin ◽  
Technical Lignins

The quest for converting lignin into high-value products has been continuously pursued in the past few decades. In its native form, lignin is a group of heterogeneous polymers comprised of phenylpropanoids. The major commercial lignin streams, including Kraft lignin, lignosulfonates, soda lignin and organosolv lignin, are produced from industrial processes including the paper and pulping industry and emerging lignocellulosic biorefineries. Although lignin has been viewed as a low-cost and renewable feedstock to replace petroleum-based materials, its utilization in polymeric materials has been suppressed due to the low reactivity and inherent physicochemical properties of lignin. Hence, various lignin modification strategies have been developed to overcome these problems. Herein, we review recent progress made in the utilization of functionalized lignins in commodity polymers including thermoset resins, blends/composites, grafted functionalized copolymers and carbon fiber precursors. In the synthesis of thermoset resins such as polyurethane, phenol-formaldehyde and epoxy, they are covalently incorporated into the polymer matrix, and the discussion is focused on chemical modifications improving the reactivity of technical lignins. In blends/composites, functionalization of technical lignins is based upon tuning the intermolecular forces between polymer components. In addition, grafted functional polymers have expanded the utilization of lignin-based copolymers to biomedical materials and value-added additives. Different modification approaches have also been applied to facilitate the application of lignin as carbon fiber precursors, heavy metal adsorbents and nanoparticles. These emerging fields will create new opportunities in cost-effectively integrating the lignin valorization into lignocellulosic biorefineries.

Surface Modification of Poly(Vinylchloride) for Manufacturing Advanced Catheters

2020 ◽  
Vol 27 (10) ◽  
pp. 1616-1633 ◽  
Author(s):  
Oana Cristina Duta ◽  
Aurel Mihail Ţîţu ◽  
Alexandru Marin ◽  
Anton Ficai ◽  
Denisa Ficai ◽  
...  
Keyword(s):  
Surface Modification ◽  
Chemical Modification ◽  
Medical Devices ◽  
Low Cost ◽  
Physical And Mechanical Properties ◽  
Polymeric Materials ◽  
Modern Medicine ◽  
Structural Failure ◽  
Chemical Grafting ◽  
One Step

Polymeric materials, due to their excellent physicochemical properties and versatility found applicability in multiples areas, including biomaterials used in tissue regeneration, prosthetics (hip, artificial valves), medical devices, controlled drug delivery systems, etc. Medical devices and their applications are very important in modern medicine and the need to develop new materials with improved properties or to improve the existent materials is increasing every day. Numerous reasearches are activated in this domain in order to obtain materials/surfaces that does not have drawbacks such as structural failure, calcifications, infections or thrombosis. One of the most used material is poly(vinylchloride) (PVC) due to its unique properties, availability and low cost. The most common method used for obtaining tubular devices that meet the requirements of medical use is the surface modification of polymers without changing their physical and mechanical properties, in bulk. PVC is a hydrophobic polymer and therefore many research studies were conducted in order to increase the hydrophilicity of the surface by chemical modification in order to improve biocompatibility, to enhance wettability, reduce friction or to make lubricious or antimicrobial coatings. Surface modification of PVC can be achieved by several strategies, in only one step or, in some cases, in two or more steps by applying several techniques consecutively to obtain the desired modification / performances. The most common processes used for modifying the surface of PVC devices are: plasma treatment, corona discharge, chemical grafting, electric discharge, vapour deposition of metals, flame treatment, direct chemical modification (oxidation, hydrolysis, etc.) or even some physical modification of the roughness of the surface.

scholarly journals Chitosan Adsorbent Derivatives for Pharmaceuticals Removal from Effluents: A Review

Macromol ◽  
2021 ◽  
Vol 1 (2) ◽  
pp. 130-154
Author(s):  
Efstathios V. Liakos ◽  
Maria Lazaridou ◽  
Georgia Michailidou ◽  
Ioanna Koumentakou ◽  
Dimitra A. Lambropoulou ◽  
...  
Keyword(s):  
Emerging Contaminants ◽  
Low Cost ◽  
Value Added ◽  
Ph Effects ◽  
Hydroxyl Groups ◽  
Research Papers ◽  
Natural Polysaccharide ◽  
Best Fitting ◽  
Isotherm And Kinetic Models ◽  
Published Research

Chitin is mentioned as the second most abundant and important natural biopolymer in worldwide scale. The main sources for the extraction and exploitation of this natural polysaccharide polymer are crabs and shrimps. Chitosan (poly-β-(1 → 4)-2-amino-2-deoxy-d-glucose) is the most important derivative of chitin and can be used in a wide variety of applications including cosmetics, pharmaceutical and biomedical applications, food, etc., giving this substance high value-added applications. Moreover, chitosan has applications in adsorption because it contains amino and hydroxyl groups in its molecules, and can thus contribute to many possible adsorption interactions between chitosan and pollutants (pharmaceuticals/drugs, metals, phenols, pesticides, etc.). However, it must be noted that one of the most important techniques of decontamination is considered to be adsorption because it is simple, low-cost, and fast. This review emphasizes on recently published research papers (2013–2021) and briefly describes the chemical modifications of chitosan (grafting, cross-linking, etc.), for the adsorption of a variety of emerging contaminants from aqueous solutions, and characterization results. Finally, tables are depicted from selected chitosan synthetic routes and the pH effects are discussed, along with the best-fitting isotherm and kinetic models.

scholarly journals Fungal Treatment for the Valorization of Technical Soda Lignin

2021 ◽  
Vol 7 (1) ◽  
pp. 39
Author(s):  
Mariane Daou ◽  
Clementina Farfan Soto ◽  
Amel Majira ◽  
Laurent Cézard ◽  
Betty Cottyn ◽  
...  
Keyword(s):  
Filamentous Fungi ◽  
Structural Changes ◽  
Molar Mass ◽  
Glycoside Hydrolases ◽  
Fungal Treatment ◽  
Industrial Transformation ◽  
Pycnoporus Sanguineus ◽  
Technical Lignin ◽  
Soda Lignin ◽  
Technical Lignins

Technical lignins produced as a by-product in biorefinery processes represent a potential source of renewable carbon. In consideration of the possibilities of the industrial transformation of this substrate into various valuable bio-based molecules, the biological deconstruction of a technical soda lignin by filamentous fungi was investigated. The ability of three basidiomycetes (Polyporus brumalis, Pycnoporus sanguineus and Leiotrametes menziesii) to modify this material, the resultant structural and chemical changes, and the secreted proteins during growth on this substrate were investigated. The three fungi could grow on the technical lignin alone, and the growth rate increased when the media were supplemented with glucose or maltose. The proteomic analysis of the culture supernatants after three days of growth revealed the secretion of numerous Carbohydrate-Active Enzymes (CAZymes). The secretomic profiles varied widely between the strains and the presence of technical lignin alone triggered the early secretion of many lignin-acting oxidoreductases. The secretomes were notably rich in glycoside hydrolases and H2O2-producing auxiliary activity enzymes with copper radical oxidases being induced on lignin for all strains. The lignin treatment by fungi modified both the soluble and insoluble lignin fractions. A significant decrease in the amount of soluble higher molar mass compounds was observed in the case of P. sanguineus. This strain was also responsible for the modification of the lower molar mass compounds of the lignin insoluble fraction and a 40% decrease in the thioacidolysis yield. The similarity in the activities of P. sanguineus and P. brumalis in modifying the functional groups of the technical lignin were observed, the results suggest that the lignin has undergone structural changes, or at least changes in its composition, and pave the route for the utilization of filamentous fungi to functionalize technical lignins and produce the enzymes of interest for biorefinery applications.

Value-added derivatives of soda lignin from alfa grass (Stipa tenacissima). I. Modification and characterization

2010 ◽  
Vol 115 (3) ◽  
pp. 1546-1554 ◽  
Author(s):  
H. Nadji ◽  
Y. Bedard ◽  
A. Benaboura ◽  
D. Rodrigue ◽  
T. Stevanovic ◽  
...  
Keyword(s):  
Value Added ◽  
Stipa Tenacissima ◽  
Soda Lignin ◽  
Derivatives Of

Value communication: low-cost marketing initiatives for “Guru Ki Bani 58282”

2013 ◽  
Vol 3 (3) ◽  
pp. 1-9
Author(s):  
Neeraj Pandey ◽  
Gaganpreet Singh
Keyword(s):  
Interactive Voice Response ◽  
Low Cost ◽  
Value Added ◽  
Subject Area ◽  
Marketing Management ◽  
Digital Marketing ◽  
Content Type ◽  
Mba Students ◽  
Marketing Team ◽  
Value Communication

Subject area Pricing, digital marketing, marketing management and strategic marketing. Study level/applicability The case can be used for pricing or digital marketing courses as well as marketing management courses to MBA students and/or for management development programmes. Case overview Goldfinch Mobile Solutions, a Hong-Kong based value added services (VAS) and gaming platform provider, had an exclusive tie up with Bharti Airtel in India for providing value added voice applications on an interactive voice response system (IVRS) platform. The Goldfinch flagship service is “Guru Ki Bani” which may be subscribed to by dialing the short code 58282. This “58282” service has a repository of all Sikh religion daily prayers, religious songs, teachings, stories from Guru's life and similar information that is derived from the Sikh Holy book Guru Granth Sahib Ji. As per mutual agreement between Goldfinch Mobile Solutions and Bharti Airtel, the telecom operator had the responsibility to promote Goldfinch's Guru Ki Bani service amongst its subscriber base through its below the line (BTL) promotional channels such as short messaging service (SMS), outbound calls, cell information, notification SMS after call and above the line (ATL) activities such as posters, leaflets, print, promoters, regional TV, outdoors, etc. The revenue sharing arrangement between Airtel and Golfinch was in the ratio of 75 percent and 25 percent. However, with recent changes in the policies of Telephone Regulatory Authority of India (TRAI), promotional marketing used by telecom operators has been constrained. Declining customer share, decreasing profits (after Bharti Airtel halted promotions) and increasing organization cost per customer have made MD and CEO Mr Newton Bubber think of various options including low-cost marketing initiatives besides digital marketing to promote Guru Ki Bani services. Value communication to its huge potential customer base, i.e. 184.19 million Bharti Airtel subscribers was another challenge facing Mr Newton and his marketing team at Goldfinch. Expected learning outcomes The case enables students to learn the concepts and application of value creation, effective value communication, price waterfall analysis, importance of costing parameters in pricing decisions, low-cost marketing strategies and digital marketing. Supplementary materials Teaching notes are available for educators only. Please contact your library to gain login details or email [email protected] to request teaching notes.

Materials Selection for Sandwich Pipes Under the Combined Effect of Pressure, Bending and Temperature

2007 ◽  
Author(s):  
Allan R. de Souza ◽  
Theodoro A. Netto ◽  
Ilson P. Pasqualino
Keyword(s):  
Structural Strength ◽  
Material Selection ◽  
Low Cost ◽  
Polymeric Materials ◽  
External Pressure ◽  
Core Material ◽  
Annular Layer ◽  
Oil And Natural Gas ◽  
Longitudinal Bending ◽  
Logic Approach

Recent researches point to the great potential of the sandwich pipe conception for ultra deepwater exploitation and production of oil and natural gas. Its configuration is very simple and comprises two concentric metallic pipes with a core material, polymeric or ceramic, in the annulus. The main functions of the annular layer are: to provide satisfactory thermal insulation so as to avoid the formation of wax and hydrates along the pipeline during production shutdown; to improve the overall structural strength of the system. Polypropylene and cement have been recently proposed for these applications. The reason for the choice of these materials was the low cost and the extensive availability in industry. Here a systematic material selection approach is employed in order to assess the applicability of other polymeric materials. The attributes of materials needed to meet the design specification are thoroughly studied. The list of possible materials was enlarged and the modified digital logic approach is used with the purpose to define a top group of materials for further numerical comparative study. Finite element analyses are carried out to assess the structural strength of the sandwich pipe under pure external pressure or longitudinal bending and combined external pressure and bending. Additionally, the effect of thermal gradient is included to the numerical analyses to evaluate each pre-selected material of the top group. Results indicate that other potential materials such as PEEK and polycarbonate can improve the structural performance of the sandwich pipe conception and yet meet other several design criteria.

Carbon Dioxide as a Carbon Resource – Recent Trends and Perspectives

2012 ◽  
Vol 67 (10) ◽  
pp. 961-975 ◽  
Author(s):  
Markus Hölscher ◽  
Christoph Gürtler ◽  
Wilhelm Keim ◽  
Thomas E. Müller ◽  
Martina Peters ◽  
...  
Keyword(s):  
Carbon Dioxide ◽  
Raw Materials ◽  
Low Cost ◽  
Polymeric Materials ◽  
Short Review ◽  
Chemical Research ◽  
Bond Forming ◽  
Bulk Chemicals ◽  
High Thermodynamic Stability ◽  
Recent Trends

With the growing perception of industrialized societies that fossil raw materials are limited resources, academic chemical research and chemical industry have started to introduce novel catalytic technologies which aim at the development of economically competitive processes relying much more strongly on the use of alternative carbon feedstocks. Great interest is given world-wide to carbon dioxide (CO2) as it is part of the global carbon cycle, nontoxic, easily available in sufficient quantities anywhere in the industrialized world, and can be managed technically with ease, and at low cost. In principle carbon dioxide can be used to generate a large variety of synthetic products ranging from bulk chemicals like methanol and formic acid, through polymeric materials, to fine chemicals like aromatic acids useful in the pharmaceutical industry. Owing to the high thermodynamic stability of CO2, the energy constraints of chemical reactions have to be carefully analyzed to select promising processes. Furthermore, the high kinetic barriers for incorporation of CO2 into C-H or C-C bond forming reactions require that any novel transformation of CO2 must inevitably be associated with a novel catalytic technology. This short review comprises a selection of the most recent academic and industrial research developments mainly with regard to innovations in CO2 chemistry in the field of homogeneous catalysis and processes.

ZnCl2 regulate flax-based porous carbon fiber for long cycle stability supercapacitors

2021 ◽  
Author(s):  
Gaigai Duan ◽  
Luying Zhao ◽  
Lian Chen ◽  
Feng Wang ◽  
Shuijian He ◽  
...  
Keyword(s):  
Carbon Fiber ◽  
Electrochemical Performance ◽  
Porous Carbon ◽  
Low Cost ◽  
Flax Fiber ◽  
Cycle Stability ◽  
Long Cycle

The flax fiber with abundant sources and low cost is an excellent precursor of carbon fiber for supercapacitor. At present, it is very attractive designing high electrochemical performance electrode via...

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