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This textbook covers the processing of advanced composites and their various technologies, with special emphasis on the distinct characteristics of processability. The book covers the impact of different processing techniques on the performance and characteristics of the final product. Written with a didactic approach, the volume contains extensive illustrations and pedagogic features (including examples and exercises) to help the reader assess and correlate existing technologies. The book will be useful as a text in graduate courses in processing of polymers and composites and can additionally be used as a professional reference.

### 1. Introduction

Abstract
Composites have existed in nature right from the evolution of life on Earth. Wood is the finest example of natural composite in which cellulose is reinforcement and lignin is matrix. The combination of bones and musculature is another example of a natural composite where bones are reinforcements and muscles are the matrix. Similarly, in orthopods, the exoskeletal body is reinforcement, and interior soft tissues are matrix. By definition, composites are the materials/structures that have two or more physically distinct constituent phases, and the resultant properties of these materials/structures are superior to the properties of its constituent phases. These phases are primarily reinforcement and matrix and are separated by a distinct interphase. Interphase has a different combination of properties from those of constituent phases. In hybrid composites, different types of reinforcements are used. A composite material also may be defined as the heterogeneous material that consists of two or more constituent materials which do not lose their characteristics. This combination of constituent materials results in new desirable properties. Normally, the constituents (reinforcement and matrix) can be physically identified along with the interface, which also generally controls the properties of the composites. The constituents can be organic, inorganic, or metallic in the form of particles, rods, fibres, plates, foams, etc., and they do not dissolve or merge completely into each other [1, 2].
Anup K. Ghosh, Mayank Dwivedi

### 2. Advantages and Applications of Polymeric Composites

Abstract
Composites have engineering advantages over conventional materials, such as metal, wood, and leather. Polymeric composites have good tensile strength, flexural strength, compressive strength, impact strength, Young’s modulus, and rigidity coupled with high dimensional stability. Depleting natural resources and related environmental concerns—specifically in the use of wood—have forced scientists and engineers to explore more applications for advanced composites. It can be said that advanced composites have come to a level where they can replace conventional materials in most engineering applications [1, 2]. Composites have proven themselves to be the best substitute for conventional materials. The advantages of polymeric composites and their applications are discussed in detail in the following sections of this chapter.
Anup K. Ghosh, Mayank Dwivedi

### 3. Micromechanics and Macromechanics of Polymeric Composites

Abstract
Mechanics of composites is an important study in the understanding of the mechanical responses and their mechanisms due to anisotropy. Micromechanics and macromechanics of composites deal with a material at its constituent and bulk levels, respectively. The understanding of the properties of the constituents—their interaction and bonding mechanisms—plays a vital role in understanding micromechanics. On the other hand, macromechanics primarily deals with engineering aspects of composite material and its responses to applied loads. This chapter explains in detail the concepts of micromechanics and macromechanics.
Anup K. Ghosh, Mayank Dwivedi

### 4. Rheology in Processing of Polymeric Composites

Abstract
Processing polymer composites is quite ubiquitous in the domain of polymer engineers. The true aspects of polymer processing have a direct correlation with rheological properties of the material concerned. The fundamental concept behind the theory of rheology dates back to the basic definition of work being done, which is dependent on two important parameters, notably force and its corresponding displacement.
$$W=F\cdot d$$
The force that is needed to displace a material from its coordinates and its centre of gravity to a new set of coordinates needs to overcome a resistance against the material to move from its position of inertia. Relating to Newton’s first law of motion, this resistance is the principal parameter that governs this entire theory. The work done corresponds to the energy that is needed to displace the body, which also goes hand in hand with the parameter known as resistance.
Anup K. Ghosh, Mayank Dwivedi

### 5. Processability of Thermosetting Composites

Abstract
The processability of polymeric composites depends upon various factors ranging from raw materials, coupling agents, additives present, processing method, mould design, processing parameters, surrounding environmental conditions, and post-fabrication handling. Uniformity in the properties of raw materials is essential for the desired processability of polymeric composites. It is quite common in reinforcements that their mechanical properties diminish once their useful life is expired. In glass fabrics, it is also seen that wet resin does not stick to its surface, indicating the loss of the coupling agent on glass fibres, thus making them hydrophilic [1, 2]. The presence of additives influences the properties of thermosetting composites, including curing of the matrix, interphase with the reinforcement, etc. The right selection of the processing method and its parameters aids in processability. Mould design and tooling too have an influence on the efficiency and quality of thermosetting composites being manufactured. The surrounding environmental conditions (such as humidity, dust, and temperature) have an influence on raw materials and processing conditions. Handling a manufactured part requires care so that further processing and finishing operations (such as printing, embossing, metalizing, etc.) can be carried out.
Anup K. Ghosh, Mayank Dwivedi

### 6. Processability of Thermoplastic Composites

Abstract
The basic principles of processability and the factors affecting it do not change much from thermosetting composites to thermoplastic composites. However, the processability factors, which have a profound effect on the processing of thermoplastic composites, are mentioned here.
Anup K. Ghosh, Mayank Dwivedi

### 7. Processability in Open Mould Processing of Polymeric Composites

Abstract
Polymeric composites offer the largest processing window among all of the engineering materials due to their wide range of available raw materials and vast horizons of processing technologies for the production of specific composites. When put together, this provides great flexibility in their processing. Advanced composites are also amenable to post-fabrication processing, such as machining and painting. The processing methods and parameters of polymeric composites depend upon the type of raw materials to be processed. The most common processing methods used for making thermoplastic (TP) matrix composites and thermosetting (TS) matrix composites are provided in ◘ Table 7.1.
Anup K. Ghosh, Mayank Dwivedi

### 8. Processability in Closed Mould Processing of Polymeric Composites

Abstract
The flexibility in composite processing provides possibilities for particular types of composites using different processing technologies, depending on the product requirement. The processing of composites and the process compatibility of composites are interlinked. Process compatibility is referred to in terms of economics of production, rate of production, processing technology, selection of raw materials, processing parameters, and post-fabrication processes. As a matter of fact, all of these parameters govern the processability of composites discussed in ► Chap. 4. The success of composite product design and production lies in the process adopted for its realization.
Anup K. Ghosh, Mayank Dwivedi

### 9. Characterization and Testing of Polymeric Composites

Abstract
The complexity of damages in composites is closely related to anisotropy and includes various mechanisms, such as interfacial debonding, matrix cracking, ply cracking, fibre breakage, and so on. It is critical to understand the evaluation of damage accurately in order to assess and predict the life of polymeric composites. From the discussion, in the preceding sections, it is understood that the composite consists of laminae, and the laminae consist of fibres and a matrix. In order to understand and assess the behaviour of polymeric composites, it is important to understand the performance of these materials under different loading conditions and operational environments. The performance of polymeric composites is dependent on factors like loading conditions (such as cyclic or static), temperature, humidity, volume fractions, exposure to radiation, and the chemical environment. The assessment of the mechanical behaviour may be carried out based on the loading conditions and service environment [1, 2].
Anup K. Ghosh, Mayank Dwivedi

### 10. Correction to: Processability of Polymeric Composites

The below listed late corrections have been carried out in the following chapters of the current version:
Anup K. Ghosh, Mayank Dwivedi