Polymer composition, traditional

Economic Benefits. The traditional costs of a product include raw materials, processing, overhead, and so forth. Designers and engineers considering potential composite appHcations cannot compare material costs only. Polymer composites, except for inexpensive fillers and small amounts of additives, consist mostly of resin and reinforcement, whose materials costs are usually higher than traditional materials. 

Fig. 14 Creation of a single specimen polymer blend phase diagram from orthogonal polymer composition and temperature gradients. The polymers are polystyrene and poly(vinyl methyl ether) (PVME) a composition library placed orthogonal to a temperature gradient b completed gradient library polymer blend phase diagram. White points are data derived from traditional measurement for comparison. See text for details, (b reproduced with permission from [3])...

Traditional composite panels are made from veneers and from mat-formed eomposites bonded by adhesive. More recently wood has also been combined (eompression moulded or extruded) with synthetic polymers, e.g. thermoplastic polymers, to make wood-polymer composites (WPC). WPC products have been growing very rapidly in the recent years, especially in the deeking market, where Woleott (2004) observed that their market share has grown from 2% in 1997 to 14% in 2003. Further, much research work has explored the use of fibre-reinforced polymers (FRP) to enhance the structural performance of engineered wood eomposites, ealled FRP-wood hybrid composites (Dagher et ai, 1998 Shi, 2002). 

Miscellaneous Extrusion-Applied Polymers. As mentioned earlier, there is a tendency to develop solventless magnet wire enamel formulations, and extrudable polymer systems would fulfill that requirement. There have been reports about extrusion of thin coatings of polyesters over copper wire. At this point, the state of the art allows extrusion of thin insulating films only with thermoplastic materials. The reliable extrusion of uniform and concentric insulating films of approximately 0.001-0.002 in. wall thickness is already an improvement over the more traditional extrusions of polyethylene, poly(vinyl chloride), and several fluoropolymers in much greater wall thicknesses. Because cross-linked insulation is ultimately required for most magnet wire applications, further materials development needs to be done to provide polymer compositions that are both extrudable as thin films and can be cross-linked in an economical process suitable for large-scale industrial application. 

Figure 6.10. Models of different types of core-shell modifiers (a) traditional core/shell (b) IPN core/shell (c) blend of separate core/shell and (d) multilayered core/shell. Possible polymer compositions are polybutadiene copolymer as polymer A, acrylic copolymer as polymer B, and SAN as polymer C.

Cqpolymerization of MCM with traditional monomers is the main technique of metal insertion into a polymer chain, and it is more widely used than their homopolymerization. However, ocpolymerization laws in such systems are difficult to analyze because of their raultiparameter dependence of the kinetics and copolymerization characteristics on the process, parameters such as pH, solvent nature and even concentration ratio (30). The metal-containing giroup in MCM is, as a rule, an electron-donor substituent (scheme Q-e). The copolymerization yields complexes of different comonomers, effecting the polymer composition and structure. In our view, the most remarkable one is cqpolymerization of transition metal diacrylates with MMA, styrene, etc. (37), as well as vinylpyridine and vinylimidazole MX complexes and formation of ternary copolymers of the following composition (38) ... 

Traditional fibres used as reinforcement in polymer composites are generally either polymers or ceramics the polymer aramids, glass, carbon, boron, aluminium oxide and silicon carbide. Carbon is a high-performance fibre material that is the most commonly used reinforcement in advanced polymer-matrix composites. Glass fibre is readily available and may be fabricated into a glass-reinforced plastic economically using a wide variety of composite-manufacturing techniques. 

LCA methodology applied in the development of new polymer composites is a relative new field, but it has already been widely used in many industrial sectors as a very useful tool to drive the choice of materials and processes towards a more sustainable production system. Several LCA applications to both traditional composites and new green composites have pointed out that the benefits of using green composites produced with natural fibres and bio-derived matrices, compared to traditional composites, appear superior, and their market opportunities are increasing for many industrial sectors. 

La Rosa, A.D., Summerscales, J., Recca, G., Latteri, A., Cozzo, G., Cicala, G., 2014b. Bio-based versus traditional polymer composites. A Ufe cycle assessment perspective. Journal of Cleaner Production 74, 135—144. 

Eulaliopsis binata fiber-reinforced polymer composites are more eco-friendly and cost effective compared to the traditional synthetic fiber-reinforced composites. The aim of the present work was to study the reinforcing potential of the Euiaiiopsis binata fibers in the short fiber form. The mechanical performance of these Euiaiiopsis binata fiber polymer composites was found to be higher than that of the pure polymer. However challenges still exist In further improving the mechanical properties of these composites to make them competitive to their synthetic counterparts. 

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