Preface
Many of the recent research accomplishments in the area of high performance polymers, their preparation, structure-properties and their nanocomposites are summarized in High Performance Polymers and Their Nanocomposites. Among the many topics discussed are liquid crystal polymers, polyamide 4,6 and polyacrylamide, and the influence of nanostructured multifunctional polyhedral oligomeric silsesquioxane on surface morphology. Also discussed are thermoplastic polyimide, and polytetrafluoroethylene's performance properties and applications. A review of polymer containing phthalazinone moieties is presented along with a discussion of poly(ethylene terephthalate) and poly(ethylene naphthalate) polyesters; high-performance oil-resistant blends of ethylene propylene diene monomer and epoxidized natural rubber; and unsaturated polyester nanocomposites reinforced with functionalized nanofillers.
This book will be a very valuable reference source for university and college faculties, professionals, post-doctoral research fellows, senior graduate students, and researchers from R&D laboratories working in the area of high performance polymers and their nanocomposites. The various chapters in this book are contributed by prominent researchers from industry, academia and government/private research laboratories across the globe, making it an up-to-date record on the major findings and observations in the field.
The first chapter discusses the state-of-the-art of high performance polymer nanocomposites and new challenges relating to them. The second chapter introduces the concepts of liquid crystal polymers (LCPs) and also gives their historical background. Because the method used to obtain these compounds is an important issue, the main synthesis routes are described. In order to understand the solution properties of LCPs some rheological aspects are highlighted, together with some basic characteristics in solid phase, like dielectric behavior, magnetic properties, mechanical resistance and phase morphology. Since the features of LCPs are also affected by the applied processing methodology, basic aspects concerning injection molding, extrusion, free surface flow and LCP fiber spinning are briefly addressed. The practical importance of blends and composites with LCP phase is emphasized in various industrial areas such as optoelectronics, displays, sensors and actuators. Several essential aspects are disclosed regarding the environmental impact of LCPs and concerns about their recycling. Considering the high demand for products based on LCPs, the corresponding market is expected to expand, but efforts still must be made to improve their performance and reduce preparation costs.
Various topics on polyamide 4,6 and its properties are discussed in the third chapter. Polyamide (PA) or nylon is one of the engineering plastics employed in many engineering components. At high temperatures, PA4,6 provides excellent properties such as high stiffness, creep resistance, thermal stability, and fatigue resistance, along with good toughness. Also, PA4,6 shows better chemical resistance to acidic salts, methanol, mineral salts, oils and grease. Its excellent mechanical properties at high temperatures, low friction, excellent resistance to wear and excellent chemical resistance make PA4,6 polymer a good candidate for a broad range of technical applications in electrical, electronic and automotive industries among others. Therefore, studies about the polymerization, properties, chemical stability, processing and applications of PA4,6 are presented in this chapter. The blends, composites and nanocomposites of PA4,6 with other polymers are also mentioned, along with its environmental impact and recycling possibility.
The fourth chapter of this book discusses polyacrylamide and its nanocomposites. Polyacrylamide (PAM) polymers are a synthetic group with a great variety of macromolecular compounds. Polyacrylamide is very soluble in water, with the solution's viscosity being linearly dependent on polymer molecular weight; and PAM amide with weak basic character undergoes hydrolysis, halogenation, methylation and sulfonation reactions. This chapter is mainly divided into two parts. The first part discusses the history of PAM and its polymerization, fabrication, properties, chemical stability, compounding, special additives, processing and applications. Whereas the second part deals with various topics such as blends and composites of PAM, its nanocomposites, environmental impact and recycling.
The effect of nanostructured polyhedral oligomeric silsesquioxone (POSS) on high performance poly(urethane-imide) (PUI) is the topic of the fifth chapter, in which the author discusses different research studies related to POSS. Successfully embedding POSS in the PUI membrane through chemical bonding and the vital role of POSS on the surface morphology of prepared membranes were studied. A range of PUI-POSS membranes were prepared by a facile in-situ polymerization reaction based on different loadings of POSS and their surface morphology was characterized by atomic force microscopy (AFM), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) techniques. The thermal stability of PUI-POSS nanocomposite membranes were analyzed by thermogravimetric analysis (TGA). The TEM images revealed the dispersion behavior of POSS in the membranes, which was found to be in the range of 10 to 20 nm size. SEM images showed no agglomeration even at the higher content of POSS. Three-dimensional AFM images of the membranes indicated a slight increase in roughness when POSS content was increased. The gel content, fractional free volume (FFV) and density of the PUI-POSS membranes were calculated, and effectively correlated with surface morphology studies. The obtained results showed that the prepared membrane is excellent for gas transport studies.
The next chapter mainly focuses on the polymerization, processing, properties and applications of thermoplastic polyimide (TPI). The polymerization and properties are introduced by their basic polymer units such as BEPA, PMDA, BTDA, ODPA, BTDA, etc. The blends, composites and nanocomposites of TPI are also described in this chapter, including compounding with other molecules of TPI. Its environmental impact and recyclability are briefly discussed at the end of the chapter.
Advances in high performance polymers containing phthalazinone moieties are discussed in the seventh chapter. The authors of the chapter explain that high performance polymer materials have excellent performance in high temperatures and are indispensable in aerospace, electronics, electrical engineering, high-speed rail, and other important high-tech fields. Progress in the synthesis and performance of phthalazinone-containing polyarylethers (including poly(phthalazinone ether sulfone ketone) s, poly(phthalazinone ether nitrile sulfone ketone)s, poly(phthalazinone ether sulfone ketone ketone)s, and poly(triaryl triazine ring)s), polyamides, polyimides, polyarylates, and polybenzimidazoles is also reviewed. Because the phenyl-phthalazinone structure is a twisted, non-coplanar, and fused ring, the above polymers are not only heat resistant, but also soluble. The processing methods are diverse and include both thermoforming (molding, extrusion, injection, etc.) and solution processing. Hence, these polymers have a wide range of applications.
In the eitgth chapter, poly(ethylene terephthalate) (PET) and poly(ethylene naphthalate) (PEN) polyesters are discussed in a wide range of review studies. The first part of this chapter discusses the synthesis of PET and PEN, PET production, processing of neat polymers, materials feeding, melting, compounding, venting, metering, temperature managing, die forming and post-die treatments, and tandem extruders configuration. The second part of the chapter relates to PET and PEN nanocomposites, in which the authors explain the preparation of polyester-based nanocomposites using different preparation methods, and also characterize them with different types of techniques.
In the ninth chapter, different topics relating to high-performance oil-resistant blends of ethylene propylene diene monomer (EPDM) and epoxidized natural rubber (ENR) are discussed. Among the many subtopics discussed in the first part of the chapter are optimization of the curing system and blend ratio for the ENR/EPDM blends, the optimization of maleic anhydride (MAH) concentration for maleation of EPDM, and the characterization and compatibility characteristics of ENR-MA-g-EPDM blends and optimization of their processing temperature. The second part of the chapter mainly focuses on characterization methods such as ultrasonic velocity measurements in solution, thermomechanical analysis, scanning electron microscopy studies, evaluation of the mechanical properties of individual rubbers and blends, stress-strain properties, determination of hardness, oil swelling and aging studies, and thermogravimetric analysis. Finally, the effect of addition of carbon black in ENR/MA-g-EPDM blend is also explained.
The subject of the final chapter is high performance unsaturated polyester/f-MWCNTs nanocomposites induced by f-graphene nanoplatelets. The focus of the chapter is mainly on the unique properties of unsaturated polyester resin (UPE) as well as preparation of a hybrid UPE nanocomposite incorporated with chemically functionalized multiwalled carbon nanotubes (f-MWCNTs) and functionalized graphene nanoplatelets (f-GNPs) through a solution mixing procedure. The chapter's authors tried to compile the detailed preparation and characterization techniques of both functionalized nanofillers and the hybrid UPE nanocomposites with a focus on the effect of nanofiller...
