Influence of processing on properties

The major processes and their influence on important composite properties are considered. Since processing also limits the shape and size of the component, this needs to be decided at an early stage in the design process. Some data are collated from preceding chapters and some from studies carried out to identify the characteristic properties of processes. 

Processing has an important influence on properties by virtue of processing requirements which affect not only size and shape of a component, but also the orientation, length and size of the reinforcement. 

The major processes are listed in Table 11.1 injection moulding is not considered further because of the restriction in this book to long length fibres. 

Only contact moulding by hand lay-up does not require dedicated equipment and it is for this reason that this process is so popular. 

The major process limitations are summarized in Table 11.2. Of these the maximum size is typical rather than the absolute value whilst shape, reinforcement length and orientation are limited by the type of process. 

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This unified approach to polymer materials science is divided into three major sections Basic Principles, Influence of Processing on Properties, and Engineering Design Properties. 

Keywords Additives, Compounding, Deformation of melts, Extrusion foaming. Flow properties, Influences of processing on properties. Injection molding. Plastic melts, Processing of elastomers and thermosets. Processing of fiber composites. Processing of thermoplastics... 

The theme of the twelve chapters which comprise this book is information which can be used for designing a fibre composite article or structure. The data cover a wide range. There is information on the short- and long-term thermomechanical and electrical properties and behaviour of fibre-reinforced polymer composites, plus their response to fire and environmental effects. Finally the influence of processing on properties and the quality assurance of the final product are also considered. 

NICOLI M c, ANESE M, PARPINEL M T (1999) Influence of processing on the antioxidant properties of fruit and vegetables , Trends Food Sci Technol, 10 (3) 94-100. 

When he interviewed with Meyer in 1926, Mark outlined a typically thorough program. He proposed a team of organic and physical chemists, and physicists who would evaluate the influence of structure on properties such as rigidity, elasticity, melting point, and water absorption. Work, he proposed, would shift toward new material development and into the manufacturing facilities to evaluate the effects of processing... 

As mentioned above, properties of a material are influenced by that material s structure, which in turn is influenced by the material s processing. To complete the circular discussion, processing methods used for a material are often dictated by the material properties. Processing or fabrication methods and their influence on materials constitute the bulk of this chapter. A brief discussion of the influence of structure on properties will help put these effects into perspective. 

Second, the use of CNTs embedded in a membrane matrix to provide nanochannels for precise separations (Fig. 30). The last example illustrates the influence of processing on the morphology of spherical silica particles produced by variation of the conditions particles can be produced as onion rings or with a hexagonal internal structure. Carbon onions can be produced and are found to have durable tribological properties (128) (Fig. 31). 

PAn s formed by both the chemical and electrochemical processes have been extensively studied to establish structure-property relationships. In this section, the structural studies of PAn are reviewed the influence of structure on properties is considered in Chapter 5. The description of PAn structure is complicated by its complexity. As described earlier, PAn can exist in six different forms (the salt or base forms of leucoemeraldine, emeraldine, and pemigraniline). In addition, the proton-ated forms of PAn also have counteranions intimately associated with the positively charged PAn chains. Finally, it has also been observed that PAn s may contain considerable amounts of solvent molecules. 

Other widely known phenomena are the influence of the incorporation of carbon-black and the influence of processing on the mechanical properties of the products. The outstanding aspects here are the massive increase in the modulus of elasticity and the drop in... 

Whereas the foregoing sub-section examined the influence of processing on structure formation and properties resulting from interactions, this section discusses the modification of molecular properties with a view to making ICPs (more) processable. In subsection 3.3 we mentioned that ICPs are insoluble and infusible. Attempts are being made to alter this state of affairs by means of various chemical measures, research into which is being tackled by a considerable number of... 

Keywords Influences of Synthesis on Properties, PolymerizatiOTi, Process Engineering, Synthesis (Manufacture, Production)... 

In the case of plastics, the influence of processing on the properties of the finished article is particularly great. For this reason, the designer of a structural component must keep the structural component dimensioning factors listed in Fig. 61 in mind. 

The above list of typical faults and their remedies show the interdependence between the parameters setup on processing machine and the selection of plasticizeifs) type(s) and concentration(s). Examples known from literature show further details of influence of plasticizers on properties of blow molded materials and on processing conditions during blow molding. 

B. Moginger, C. Lutz, A. Polsak and U. Fritz, Influence of processing on mechanical properties and morphology of PBT, Kunststoffe, 81 251-255,1991. 

The classification of mechanical properties is by resin type in Chapter 4 and by fibre type in Chapter 5. This is consistent with the way in which the materials are used. The influence of processing on both material selection and properties is discussed in Chapter 11, and may restrict the choices set out in Chapters 4 and 5. 

In the preparation and processing of ionomers, plasticizers may be added to reduce viscosity at elevated temperatures and to permit easier processing. These plasticizers have an effect, as well, on the mechanical properties, both in the rubbery state and in the glassy state these effects depend on the composition of the ionomer, the polar or nonpolar nature of the plasticizer and on the concentration. Many studies have been carried out on plasticized ionomers and on the influence of plasticizer on viscoelastic and relaxation behavior and a review of this subject has been given 119]. However, there is still relatively little information on effects of plasticizer type and concentration on specific mechanical properties of ionomers in the glassy state or solid state. 

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