Polyester-based composites manufacture

A wide range of biodegradable polyester-based composites is available in the new era of novel materials. Polyester-based composites are mainly manufactured by reinforcing with glass/carbon and natural fibers. The use of natural fibers as reinforcement has increased in the last two decades, because of their easy availability and degradable property. Polyester composites reinforced by glass or carbon fibers... 

At the outset of the composites industry, the matrices were unsaturated polyesters. Then other thermosets were developed but some years ago the manufacture of thermoplastic composites began and their development is now faster than that of thermoset-based composites. 

Biodegradable Polyester-Based Blends and Composites Manufacturing, Properties, and Applications... 

Similar to all commercial plastics, the traditional and more commonly used thermosetting resins are considered as petrochemicals, having been manufactured from petroleum. Some of the primary distillation products of crude oil, which can be classified either as olefins or aromatics, serve as precursors for the synthesis of thermosets. For example, epoxy resins are manufactured by the reaction of epichlorohydrin, a chloro-oxirane, and a derivative of propylene, with bisphenol A, which is a derivative of cumene. Another example would be the unsaturated polyesters (UPs), which are derivatives ultimately originating from ethylene (ethylene glycol) and benzene (maleic acid) [6]. Epoxies and polyesters constitute more than 95% of the thermoset composite market of the two, polyester-based systems predominate in volume by about 10-fold [6, 7]. Other thermoset resins used in reinforced form are phenolics, vinyl esters, and polyimides. Details of the properties and applications of these thermoset systems will be further discussed in the following section. 

The most successful application of the RIM-process is in the production of polyurethane-based materials. Other systems, such as composites based on polycaproamide, epoxy resins, and unsaturated polyesters can also be processed by reactive injection molding. New reactive systems have also been specially created for the RIM-process260 because of the exceptional opportunities it offers for manufacture of finished articles from engineering plastics with a high modulus of elasticity and impact strength. The automotive industry, which is the main customer for RIM-articles, can utilize this technology to manufacture of massive parts such as body panels, covers, wings, bumpers and other made of newly developed plastics. 

The results described in this paper were all obtained from tests on E-glass reinforced composite materials produced by hand lay-up. This is the manufacturing route most frequently used for marine structures. For the majority of the tests reported here the E-glass fibres were either quasi-unidirectional (250 g/m with 1 g/m of polyester fibres bonded in the 90° direction to keep the UD fibres in place) or stitched quadrlaxial (0/45/907-45° 1034 g/m ) cloths. The same uniaxial ply is used in both cloths. The resin is based on DGEBA epoxy (SRI500) with an amine hardener (2505) from Sicomin, France. All epoxy specimens were post-cured at 90°C for 6 hours. Some results are also shown for a woven glass (0/90° 500 g/m ) reinforced isophthalic polyester for comparison, as this is the traditional marine... 

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