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1.
Int J Biol Macromol ; 256(Pt 1): 128256, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38000585

RESUMO

The potential for the transformation of lignocellulosic biomass into valuable commodities is rapidly growing through an environmentally sustainable approach to harness its abundance, cost-effectiveness, biodegradability, and environmentally friendly nature. Ionic liquids (ILs) have received considerable and widespread attention as a promising solution for efficiently dissolving lignocellulosic biomass. The fact that ILs can act as solvents and reagents contributes to their widespread recognition. In particular, ILs are desirable because they are inert, non-toxic, non-flammable, miscible in water, recyclable, thermally and chemically stable, and have low melting points and outstanding ionic conductivity. With these characteristics, ILs can serve as a reliable replacement for traditional biomass conversion methods in various applications. Thus, this comprehensive analysis explores the conversion of lignocellulosic biomass using ILs, focusing on main components such as cellulose, hemicellulose, and lignin. In addition, the effect of multiple parameters on the separation of lignocellulosic biomass using ILs is discussed to emphasize their potential to produce high-value products from this abundant and renewable resource. This work contributes to the advancement of green technologies, offering a promising avenue for the future of biomass conversion and sustainable resource management.


Assuntos
Líquidos Iônicos , Lignina , Biomassa , Solventes , Celulose
2.
Polymers (Basel) ; 15(13)2023 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-37447565

RESUMO

Phosphorous is an essential element for the life of organisms, and phosphorus-based compounds have many uses in industry, such as flame retardancy reagents, ingredients in fertilizers, pyrotechnics, etc. Ionic liquids are salts with melting points lower than the boiling point of water. The term "polymerized ionic liquids" (PILs) refers to a class of polyelectrolytes that contain an ionic liquid (IL) species in each monomer repeating unit and are connected by a polymeric backbone to form macromolecular structures. PILs provide a new class of polymeric materials by combining some of the distinctive qualities of ILs in the polymer chain. Ionic liquids have been identified as attractive prospects for a variety of applications due to the high stability (thermal, chemical, and electrochemical) and high mobility of their ions, but their practical applicability is constrained because they lack the benefits of both liquids and solids, suffering from both leakage issues and excessive viscosity. PILs are garnering for developing non-volatile and non-flammable solid electrolytes. In this paper, we provide a brief review of phosphonium-based PILs, including their synthesis route, properties, advantages and drawbacks, and the comparison between nitrogen-based and phosphonium-based PILs. As phosphonium PILs can be used as polymer electrolytes in lithium-ion battery (LIB) applications, the conductivity and the thermo-mechanical properties are the most important features for this polymer electrolyte system. The chemical structure of phosphonium-based PILs that was reported in previous literature has been reviewed and summarized in this article. Generally, the phosphonium PILs that have more flexible backbones exhibit better conductivity values compared to the PILs that consist of a rigid backbone. At the end of this section, future directions for research regarding PILs are discussed, including the use of recyclable phosphorus from waste.

3.
Polymers (Basel) ; 14(20)2022 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-36298039

RESUMO

Chemical sensors are a rapidly developing technology that has received much attention in diverse industries such as military, medicine, environmental surveillance, automotive power and mobility, food manufacturing, infrastructure construction, product packaging and many more. The mass production of low-cost devices and components for use as chemical sensors is a major driving force for improvements in each of these industries. Recently, studies have found that using renewable and eco-friendly materials would be advantageous for both manufacturers and consumers. Thus, nanotechnology has led to the investigation of nanocellulose, an emerging and desirable bio-material for use as a chemical sensor. The inherent properties of nanocellulose, its high tensile strength, large specific surface area and good porous structure have many advantages in its use as a composite material for chemical sensors, intended to decrease response time by minimizing barriers to mass transport between an analyte and the immobilized indicator in the sensor. Besides which, the piezoelectric effect from aligned fibers in nanocellulose composites is beneficial for application in chemical sensors. Therefore, this review presents a discussion on recent progress and achievements made in the area of nanocellulose composites for chemical sensing applications. Important aspects regarding the preparation of nanocellulose composites using different functionalization with other compounds are also critically discussed in this review.

4.
Polymers (Basel) ; 14(8)2022 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-35458295

RESUMO

Biomimetics is the field of obtaining ideas from nature that can be applied in science, engineering, and medicine. The usefulness of cellulose nanocrystals (CNC) and their excellent characteristics in biomimetic applications are exciting and promising areas of present and future research. CNCs are bio-based nanostructured material that can be isolated from several natural biomasses. The CNCs are one-dimensional with a high aspect ratio. They possess high crystalline order and high chirality when they are allowed to assemble in concentrated dispersions. Recent studies have demonstrated that CNCs possess remarkable optical and chemical properties that can be used to fabricate liquid crystals. Research is present in the early stage to develop CNC-based solvent-free liquid crystals that behave like both crystalline solids and liquids and exhibit the phenomenon of birefringence in anisotropic media. All these characteristics are beneficial for several biomimetic applications. Moreover, the films of CNC show the property of iridescent colors, making it suitable for photonic applications in various devices, such as electro-optical devices and flat panel displays.

5.
Polymers (Basel) ; 14(1)2022 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-35012203

RESUMO

Recent developments within the topic of biomaterials has taken hold of researchers due to the mounting concern of current environmental pollution as well as scarcity resources. Amongst all compatible biomaterials, polycaprolactone (PCL) is deemed to be a great potential biomaterial, especially to the tissue engineering sector, due to its advantages, including its biocompatibility and low bioactivity exhibition. The commercialization of PCL is deemed as infant technology despite of all its advantages. This contributed to the disadvantages of PCL, including expensive, toxic, and complex. Therefore, the shift towards the utilization of PCL as an alternative biomaterial in the development of biocomposites has been exponentially increased in recent years. PCL-based biocomposites are unique and versatile technology equipped with several importance features. In addition, the understanding on the properties of PCL and its blend is vital as it is influenced by the application of biocomposites. The superior characteristics of PCL-based green and hybrid biocomposites has expanded their applications, such as in the biomedical field, as well as in tissue engineering and medical implants. Thus, this review is aimed to critically discuss the characteristics of PCL-based biocomposites, which cover each mechanical and thermal properties and their importance towards several applications. The emergence of nanomaterials as reinforcement agent in PCL-based biocomposites was also a tackled issue within this review. On the whole, recent developments of PCL as a potential biomaterial in recent applications is reviewed.

6.
Polymers (Basel) ; 13(19)2021 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-34641067

RESUMO

The wide availability and diversity of dangerous microbes poses a considerable problem for health professionals and in the development of new healthcare products. Numerous studies have been conducted to develop membrane filters that have antibacterial properties to solve this problem. Without proper protective filter equipment, healthcare providers, essential workers, and the general public are exposed to the risk of infection. A combination of nanotechnology and biosorption is expected to offer a new and greener approach to improve the usefulness of polysaccharides as an advanced membrane filtration material. Nanocellulose is among the emerging materials of this century and several studies have proven its use in filtering microbes. Its high specific surface area enables the adsorption of various microbial species, and its innate porosity can separate various molecules and retain microbial objects. Besides this, the presence of an abundant OH groups in nanocellulose grants its unique surface modification, which can increase its filtration efficiency through the formation of affinity interactions toward microbes. In this review, an update of the most relevant uses of nanocellulose as a new class of membrane filters against microbes is outlined. Key advancements in surface modifications of nanocellulose to enhance its rejection mechanism are also critically discussed. To the best of our knowledge, this is the first review focusing on the development of nanocellulose as a membrane filter against microbes.

7.
Polymers (Basel) ; 13(17)2021 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-34503011

RESUMO

The utilization of lignocellulosic biomass in various applications has a promising potential as advanced technology progresses due to its renowned advantages as cheap and abundant feedstock. The main drawback in the utilization of this type of biomass is the essential requirement for the pretreatment process. The most common pretreatment process applied is chemical pretreatment. However, it is a non-eco-friendly process. Therefore, this review aims to bring into light several greener pretreatment processes as an alternative approach for the current chemical pretreatment. The main processes for each physical and biological pretreatment process are reviewed and highlighted. Additionally, recent advances in the effect of different non-chemical pretreatment approaches for the natural fibres are also critically discussed with a focus on bioproducts conversion.

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