Fiber reinforced glass composites applications

As first described in Section 1.4.2, there are a number of ways of further classifying fiber-matrix composites, such as according to the fiber and matrix type—for example, glass-fiber-reinforced polymer composites (GFRP) or by fiber orientation. In this section, we utilize all of these combinations to describe the mechanical properties of some important fiber-reinforced composites. Again, not all possible combinations are covered, but the principles involved are applicable to most fiber-reinforced composites. We begin with some theoretical aspects of strength and modulus in composites. 

Carbon fiber reinforced ceramic composites also find some important applications. Carbon is an excellent high temperature material when used in an inert or nonoxidizing atmosphere. In carbon fiber reinforced ceramics, the matrix may be carbon or some other glass or ceramic. Unlike other nonoxide ceramics, carbon powder is nonsinterable. Thus, the carbon matrix is generally obtained from pitch or phenolic resins. Heat treatment decomposes the pitch or phenolic to carbon. Many pores are formed during this conversion from a hydrocarbon to carbon. Thus, a dense and strong pore-free carbon/carbon composite is not easy to fabricate. 

Cellulosic fiber reinforced polymeric composites find applications in many fields ranging from the construction industry to the automotive industry. The reinforcing efficiency of natural fiber is related to the namre of cellulose and its crystallinity. The main components of natural fibers are cellulose (a-cellulose), hemicelluloses, lignin, pectins, and waxes. For example, biopolymers or synthetic polymers reinforced with natural or biofibers (termed biocomposites) are a viable alternative to glass fiber composites. The term biocomposite is now being applied to a staggering range of materials derived wholly or in part from renewable biomass resources [23]. 

Printed Circuitry. Printed circuitry, which represents a most intricate structure of polymers and conductors, is frequently made by laminating copper foil onto glass-fiber-reinforced epoxy composites. For certain specialty applications, more expensive fiber-reinforced polyimides are used. 

It should be noted, however, that the thermal and mechanical properties of vegetable fiber reinforced polymer composites are notoriously lower than those of similar composites reinforced with synthetic fibers (e.g., carbon, glass, aramid) [1, 2,12]. The above-mentioned techniques, i.e., fiber drying and surface treatment or the addition of a compatibilizer, are mostly not enough to adjust the properties of vegetable fiber reinforced polymers to the desired level. Moreover, even though these treatments enhance adhesion, there is some controversy in the literature about their effect on the mechanical properties of the fiber itself and even when a more pronoxmced gain is noticed after treatment, the improvement for the composite is often within the scatter of the results. In addition, the cost and environmental impact of some of these treatments, especially of those more elaborated, often prevent their industrial scale applications. 

Keywords automotive, automotive application, car components, automotive requirements, substitution of metals and polymers, interior parts, exterior parts, electrical applications, filled PP, elastomer-modified PP, thermoplastic polyolefins (TPO), GMT-PP, long-fiber reinforced PP, composites, market trends, glass fiber (GF) reinforcement. 

In commercial use a common application of aU of these materials is in the form of glass fiber reinforced polymer composites see Sections 13.7 and 13.8. The glass fiber provides a significant toughening for these materials. For other applications, a variety of fillers are commonly used. 

Cellulose fibers in the form of papers and cotton had been used in combination with phenol-formaldehyde polymer as one of the earUest fiber-polymer composites [12]. Glass fibers later came on the scene and contributed to the commerciahzation of fiber-reinforced plastics [13]. The technical appHcations of fiber-reinforced plastic composites are shown in Figure 13.2. At least 50% of the fiber-reinforced plastics is used for automotive and construction applications. 

Fiber-reinforced thermoplastic composites employed in outdoor applications (mainly in automotive industry) were designed to respond to specific loads over a wide range of stress factors. Thus, it was experimentally confirmed that the presence of glass fiber reinforcement reduced the sensitivity of the material towards the application of tensile stress during UV irradiation [99, 100]. Moreover, tensile stress favoured the diffusion of small radicals formed during polymer degradation. 

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