There is, I think, something ethereal about i —the square root of minus one. I remember first hearing about it at school. It seemed an odd beast at that time—an intruder hovering on the edge of reality.

Usually familiarity dulls this sense of the bizarre, but in the case of i it was the reverse: over the years the sense of its surreal nature intensified. It seemed that it was impossible to write mathematics that described the real world in …

I and i

Carbon nanotube–polymer composites: Chemistry, processing, mechanical and electrical properties

We present the science and technology roadmap for graphene, related two-dimensional crystals, and hybrid systems, targeting an evolution in technology, that might lead to impacts and benefits reaching into most areas of society. This roadmap was developed within the framework of the European Graphene Flagship and outlines the main targets and research areas as best understood at the start of this ambitious project. We provide an overview of the key aspects of graphene and related materials (GRMs), ranging from fundamental research challenges to a variety of applications in a large number of sectors, highlighting the steps necessary to take GRMs from a state of raw potential to a point where they might revolutionize multiple industries. We also define an extensive list of acronyms in an effort to standardize the nomenclature in this emerging field.

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Science and technology roadmap for graphene, related two-dimensional crystals, and hybrid systems

This review is designed to be a comprehensive source for polymer nanocomposite research, including fundamental structure/property relationships, manufacturing techniques, and applications of polymer nanocomposite materials. In addition to presenting the scientific framework for the advances in polymer nanocomposite research, this review focuses on the scientific principles and mechanisms in relation to the methods of processing and manufacturing with a discussion on commercial applications and health/safety concerns (a critical issue for production and scale-up). Hence, this review offers a comprehensive discussion on technology, modeling, characterization, processing, manufacturing, applications, and health/safety concerns for polymer nanocomposites.

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Review article: Polymer-matrix Nanocomposites, Processing, Manufacturing, and Application: An Overview

5. In Situ Polymerization 3907 5.1. General Polymerization 3907 5.2. Photopolymerization 3910 5.3. Surface-Initiated Polymerization 3912 5.4. Other Methods 3913 6. Colloidal Nanocomposites 3913 6.1. Sol-Gel Process 3914 6.2. In Situ Polymerization 3916 6.2.1. Emulsion Polymerization 3917 6.2.2. Emulsifier-Free Emulsion Polymerization 3919 6.2.3. Miniemulsion Polymerization 3920 6.2.4. Dispersion Polymerization 3921 6.2.5. Other Polymerization Methods 3923 6.2.6. Conducting Nanocomposites 3924 6.3. Self Assembly 3926 7. Other Preparative Methods 3926 8. Characterization and Properties 3928 8.1. Chemical Structure 3928 8.2. Microstructure and Morphology 3929 8.3. Mechanical Properties 3933 8.3.1. Tensile, Impact, and Flexural Properties 3933 8.3.2. Hardness 3936 8.3.3. Fracture Toughness 3937 8.3.4. Friction and Wear Properties 3937 8.4. Thermal Properties 3938 8.5. Flame-Retardant Properties 3941 8.6. Optical Properties 3942 8.7. Gas Transport Properties 3943 8.8. Rheological Properties 3945 8.9. Electrical Properties 3945 8.10. Other Characterization Techniques 3946 9. Applications 3947 9.1. Coatings 3947 9.2. Proton Exchange Membranes 3948 9.3. Pervaporation Membranes 3948 9.4. Encapsulation of Organic Light-Emitting Devices 3948

Polymer/Silica Nanocomposites: Preparation, Characterization, Properties, and Applications

Lignocellulosic biomass has been acknowledged for potential use to produce chemicals and biomaterials. Lignin is the second most abundant natural polymer with cellulose being number one, making up to 10–25% of lignocellulosic biomass. Lignin is a three-dimensional, highly cross-linked macromolecule composed of three types of substituted phenols, which include: coniferyl, sinapyl, and p-coumaryl alcohols by enzymatic polymerization, yielding a vast number of functional groups and linkages. There is a wide range of lignin sources available, including: jute, hemp, cotton, and wood pulp. Hence, the lignin's physical and chemical behavior will be different with respect to the original source and extraction method used. The objective of this research is to extract lignin from nonwood cellulosic biomass (Wheat straw, Pine straw, Alfalfa, Kenaf, and Flax fiber) by formic acid treatment followed by peroxyformic acid treatment for the potential use as a partial replacement for the phenol precursor in resole phenolic systems. Isolated lignins were purified to remove impurities and characterized by Fourier transform infrared spectroscopy (FTIR), Thermogravimetric analysis (TGA) and Differential scanning calorimetry (DSC) analysis to compare thermal properties and chemical composition. It was found that lignin obtained from alfalfa provided the greatest yield of the various sources. Enthalpy measurements were higher for lignin from flax fiber and alfalfa at 190.57 and 160.90 J/g, respectively. The source of lignin samples was seen to affect the thermal properties. Overall, lignin extracted from wheat straw had the greatest thermal stability followed very closely by that obtained from flax fiber.

Extraction and characterization of lignin from different biomass resources

Fabrication and mechanical characterization of carbon/SiC-epoxy nanocomposites

In this study, a high-intensity ultrasonic liquid processor was used to obtain a homogeneous mixture of epoxy resin and multi-walled carbon nanotubes (CNTs). The CNTs were infused into epon 862 epoxy resin through sonic cavitation and then mixed with W curing agent using a high-speed mechanical agitator. The trapped air and reaction volatiles were removed from the mixture using a high vacuum. Flexural tests and fracture toughness tests were performed on unfilled and CNT-filled epoxy to identify the effect of adding CNTs on the mechanical properties of epoxy. The highest improvement in strength and fracture toughness was obtained with 0.3 wt% CNT loading. The nanophased matrix filled with 0.3 wt% CNT was then used with weave carbon fabric in a vacuum-assisted resin transfer molding (VARTM) set up to fabricate composite panels. Flexural tests, thermogravimetric analysis (TGA), and dynamic mechanical analysis (DMA) were performed to evaluate the effectiveness of adding CNTs on the mechanical and thermal properties of the composite. The glass transition temperature, decomposition temperature, and flexural strengths were improved by infusing CNTs. Based on the experimental result, a linear damage model has been combined with the Weibull distribution function to establish a constitutive equation for neat and nanophased carbon/epoxy. Simulated result show that that infusing CNTs increases Weiubll scale parameter, but decrease Weibull shape parameter.

Fabrication and characterization of carbon/epoxy composites mixed with multi-walled carbon nanotubes

Nanotechnology is presently seen as one of the most promising approaches in the field of materials science towards the development of advanced materials for future engineering applications. Recent and ongoing researches on polymer/inorganic nanocomposite have shown dramatic enhancements in thermal, mechanical and chemical properties over the neat polymer without compromising density, toughness, and processibility. This study investigates the effects of different types of nanoparticles on thermal and mechanical performance of rigid polyurethane (PUR) foam. Three different types of nanoparticles, namely spherical TiO 2 , platelet nanoclay, and rod-shaped carbon nanofibers (CNFs) are considered. A sonication technique is used to disperse the nanoparticles into part-A of the PUR foam precursor followed by mechanical mixing into part-B and then the whole mixture is poured into a preheated aluminum mold and cured inside the oven. In all cases only 1 wt.% nanoparticles are used, and have found significant thermal and mechanical properties enhancement of the nanophased foam. Among nanoparticles, CNFs infused PUR foam shows maximum enhancement, whereas TiO 2 infused PUR foam shows the minimum.

Shaik Jeelani

Papers

Extraction and characterization of lignin from different biomass resources

Fabrication and mechanical characterization of carbon/SiC-epoxy nanocomposites

Fabrication and characterization of carbon/epoxy composites mixed with multi-walled carbon nanotubes

Enhancement in thermal and mechanical properties of polyurethane foam infused with nanoparticles

Studies on the low-velocity impact response of woven hybrid composites