Development in Additive Methods in Aramid Fiber Surface Modification to Increase Fiber-Matrix Adhesion: A Review

This review article highlights and summarizes the recent developments in the field of surface modification methods for aramid fibers. Special focus is on methods that create a multifunctional fiber surface by incorporating nanostructures and enabling mechanical interlocking. To give a complete picture of adhesion promotion with aramids, the specific questions related to the challenges in aramid-matrix bonding are also shortly presented. The main discussion of the surface modification approaches is divided into sections according to how material is added to the fiber surface; (1) coating, (2) grafting and (3) growing. To provide a comprehensive view of the most recent developments in the field, other methods with similar outcomes, are also shortly reviewed. To conclude, future trends and insights are discussed.

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π-Electron rich small molecule sensors for the recognition of nitroaromatics

Chemical Communications ◽

10.1039/c5cc07513k ◽

2015 ◽

Vol 51 (89) ◽

pp. 16014-16032 ◽

Cited By ~ 189

Author(s):

Sankarasekaran Shanmugaraju ◽

Partha Sarathi Mukherjee

Keyword(s):

Small Molecule ◽

Fluorescent Sensors ◽

Review Article ◽

Special Focus ◽

Nitroaromatic Explosives ◽

Recent Developments ◽

Made In

In this review article we provide an overview of the recent developments made in small molecule-based turn-off fluorescent sensors for nitroaromatic explosives with special focus on organic and H-bonded supramolecular sensors.

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Recent Developments in the Downstream Processing of Phycobiliproteins from Algae: A Review

Current Biochemical Engineering ◽

10.2174/2212711906999210101230613 ◽

2021 ◽

Vol 06 ◽

Author(s):

Ayekpam Chandralekha Devi ◽

G. K. Hamsavi ◽

Simran Sahota ◽

Rochak Mittal ◽

Hrishikesh A. Tavanandi ◽

...

Keyword(s):

Cell Wall ◽

Large Scale ◽

Downstream Processing ◽

Review Article ◽

Current Status ◽

Wall Structure ◽

Scale Production ◽

Cell Wall Disruption ◽

Recent Developments ◽

Macro Algae

Abstract: Algae (both micro and macro) have gained huge attention in the recent past for their high commercial value products. They are the source of various biomolecules of commercial applications ranging from nutraceuticals to fuels. Phycobiliproteins are one such high value low volume compounds which are mainly obtained from micro and macro algae. In order to tap the bioresource, a significant amount of work has been carried out for large scale production of algal biomass. However, work on downstream processing aspects of phycobiliproteins (PBPs) from algae is scarce, especially in case of macroalgae. There are several difficulties in cell wall disruption of both micro and macro algae because of their cell wall structure and compositions. At the same time, there are several challenges in the purification of phycobiliproteins. The current review article focuses on the recent developments in downstream processing of phycobiliproteins (mainly phycocyanins and phycoerythrins) from micro and macroalgae. The current status, the recent advancements and potential technologies (that are under development) are summarised in this review article besides providing future directions for the present research area.

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Numerical Taxonomy in Marketing Analysis: A Review Article

Journal of Marketing Research ◽

10.1177/002224376800500112 ◽

1968 ◽

Vol 5 (1) ◽

pp. 83-94 ◽

Cited By ~ 27

Author(s):

Ronald E. Frank ◽

Paul E. Green

Keyword(s):

Numerical Taxonomy ◽

Review Article ◽

Numerical Classification ◽

Classification Problems ◽

Recent Developments ◽

Marketing Analysis

Recent developments in numerical taxonomy appear to show applicability for many classification problems in marketing. This review article describes some of the approaches to numerical classification and presents illustrative marketing applications. Current limitations of the procedures are also discussed.

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Recent Developments on Five-Component Reactions

Molecules ◽

10.3390/molecules26071986 ◽

2021 ◽

Vol 26 (7) ◽

pp. 1986

Author(s):

Xiaoming Ma ◽

Sanjun Zhi ◽

Wei Zhang

Keyword(s):

Multicomponent Reactions ◽

High Efficiency ◽

Review Article ◽

Reaction Centers ◽

Synthetic Approach ◽

Recent Developments

Multicomponent reactions (MCRs) have inherent advantages in pot, atom, and step economy (PASE). This important green synthetic approach has gained increasing attention due to high efficiency, minimal waste, saving resources, and straightforward procedures. Presented in this review article are the recent development on 5-compoment reactions (5CRs) of the following six types: (I) five different molecules A + B + C + D + E; pseudo-5CRs including (II) 2A + B + C + D, (III) 2A + 2B + C, (IV) 3A + B + C, (V) 3A + 2B, and (VI) 4A + B. 5CRs with more than five-reaction centers are also included.

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Recent Developments in Lignin- and Tannin-Based Non-Isocyanate Polyurethane Resins for Wood Adhesives—A Review

Applied Sciences ◽

10.3390/app11094242 ◽

2021 ◽

Vol 11 (9) ◽

pp. 4242

Author(s):

Manggar Arum Aristri ◽

Muhammad Adly Rahandi Lubis ◽

Sumit Manohar Yadav ◽

Petar Antov ◽

Antonios N. Papadopoulos ◽

...

Keyword(s):

Automotive Industry ◽

Polymeric Materials ◽

Review Article ◽

Future Perspectives ◽

Wood Adhesives ◽

Adhesion Properties ◽

Lighting Industry ◽

Renewable Natural Resources ◽

Recent Developments ◽

Strong Adhesion

This review article aims to summarize the potential of using renewable natural resources, such as lignin and tannin, in the preparation of NIPUs for wood adhesives. Polyurethanes (PUs) are extremely versatile polymeric materials, which have been widely used in numerous applications, e.g., packaging, footwear, construction, the automotive industry, the lighting industry, insulation panels, bedding, furniture, metallurgy, sealants, coatings, foams, and wood adhesives. The isocyanate-based PUs exhibit strong adhesion properties, excellent flexibility, and durability, but they lack renewability. Therefore, this study focused on the development of non-isocyanate polyurethane lignin and tannin resins for wood adhesives. PUs are commercially synthesized using polyols and polyisocyanates. Isocyanates are toxic, costly, and not renewable; thus, a search of suitable alternatives in the synthesis of polyurethane resins is needed. The reaction with diamine compounds could result in NIPUs based on lignin and tannin. The research on bio-based components for PU synthesis confirmed that they have good characteristics as an alternative for the petroleum-based adhesives. The advantages of improved strength, low curing temperatures, shorter pressing times, and isocyanate-free properties were demonstrated by lignin- and tannin-based NIPUs. The elimination of isocyanate, associated with environmental and human health hazards, NIPU synthesis, and its properties and applications, including wood adhesives, are reported comprehensively in this paper. The future perspectives of NIPUs’ production and application were also outlined.

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Chemical Modification as a Method of Improving Biocompatibility of Carbon Nonwovens

Materials ◽

10.3390/ma14123198 ◽

2021 ◽

Vol 14 (12) ◽

pp. 3198

Author(s):

Justyna Frączyk ◽

Sylwia Magdziarz ◽

Ewa Stodolak-Zych ◽

Ewa Dzierzkowska ◽

Dorota Puchowicz ◽

...

Keyword(s):

Surface Modification ◽

Cellular Response ◽

Fiber Surface ◽

Thermal Conversion ◽

Cartilage Tissue ◽

Polar Component ◽

Nonwoven Fabrics ◽

Biological Compatibility ◽

Starting Point

It was shown that carbon nonwoven fabrics obtained from polyacrylonitrile fibers (PAN) by thermal conversion may be modified on the surface in order to improve their biological compatibility and cellular response, which is particularly important in the regeneration of bone or cartilage tissue. Surface functionalization of carbon nonwovens containing C–C double bonds was carried out using in situ generated diazonium salts derived from aromatic amines containing both electron-acceptor and electron-donor substituents. It was shown that the modification method characteristic for materials containing aromatic structures may be successfully applied to the functionalization of carbon materials. The effectiveness of the surface modification of carbon nonwoven fabrics was confirmed by the FTIR method using an ATR device. The proposed approach allows the incorporation of various functional groups on the nonwovens’ surface, which affects the morphology of fibers as well as their physicochemical properties (wettability). The introduction of a carboxyl group on the surface of nonwoven fabrics, in a reaction with 4-aminobenzoic acid, became a starting point for further modifications necessary for the attachment of RGD-type peptides facilitating cell adhesion to the surface of materials. The surface modification reduced the wettability (θ) of the carbon nonwoven by about 50%. The surface free energy (SFE) in the chemically modified and reference nonwovens remained similar, with the surface modification causing an increase in the polar component (ɣp). The modification of the fiber surface was heterogeneous in nature; however, it provided an attractive site of cell–materials interaction by contacting them to the fiber surface, which supports the adhesion process.

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