Resins with carbon fibers

PEI resins reinforced with up to 40 wt % fiber glass are available. The American Cyanamid Co. uses an Ultem-type resin with carbon fibers to form their Cypac 1000 series prepregs (31). The moisture content of the resin must be less than 0.05% prior to melt processing to minimise thermal degradation. 

Liu et al. [72] used POSS nanomodification in phenolic resin with carbon fiber reinforcement. SEM analysis showed the production of best charred surface on burnt samples that enhanced the ablation performance. Novel flake graphite was introduced into barium-phenolic resin by Yu and Wan [73]. Nanocomposites were made by roller-coating technology and its ablation property was tested under long pulse laser radiation. Nanocomposites showed better ablation performance compared to the control system. It was also observed that the size of the graphite flake affected the ablation rate [73]. Srikanth et al. [74] prepared ablative nanocomposites by introducing nanosilica into the phenolic resin with carbon fiber reinforcement. Ablation resistance of nanocomposites increased with the nanosilica content up to 2 wt%. However, beyond this point ablation resistance decreased. 

Carbon—carbon composites are used in high temperature service for aerospace and aircraft appHcations as weU as for corrosion-resistant industrial pipes and housings. AppHcations include rocket nozzles and cases, aircraft brakes, and sateUite stmctures. Carbonized phenoHc resin with graphite fiber functioned effectively as the ablative shield in orbital re-entry vehicles for many years (92). 

Eig. 10. The variation of the density of carbon-fiber reinforced epoxy resin with the fiber volume fraction, based on the rule of mixtures. 

Figure 5.6 Dynetek composite cylinders consisting of an aluminum cylinderwrapped with carbon fibers (top and left) in an epoxy resin. Module with 10 cylinders (right) [6]. Companies that produce these tanks are Quantum Technologies, Lincoln Composites, Dynetek Industries and Advanced Lightweight Engineering (ALE).

In Table 15.3 are shown the chemical structures and Tg and of some representative thermoplastic polymers for use at high temperature (3,9). These matrices have high continuous service temperatures (120-200° C) even under wet environmental conditions. Advantages of thermoplastic over thermoset matrices are their shorter fabrication cycle (generally controlled environment storage is not required) and the possibility to be reprocessed and reconsolidated after manufacture. Poly(ether ether ketone) is a strong contender with epoxy resins for use as a matrix in composite prepregs with carbon fibers to be utilized in structural aircraft components. 

Fibers having an aspect ratio of above 10, such as glass fibers, asbestos, wollastonite, cellulose fibers, carbon fibers, and whiskers, act as reinforcing agents. Composites may be classified into four groups, as shown in Table II. In modern composites, such as in the case of epoxy resins reinforced with carbon fibers (51). the polymer matrix has only a secondary function to separate the individual fibers from one another and to transfer energy to the fiber surface the fibers almost completely withstand the mechanical load. 

With resin and carbon fiber, we can build a New Economy. ... 

Another commonly used surface modification method of the reinforcing fibers consists in the treatment with aminoalkylsilanes, for example y-aminopropyltriethoxysilane. Glass fibers, which have been sized in this manner, are incorporated in numerous PPE-containing compositions. In addition, it is always necessary to modify the composition of the thermoplastic matrix to bond the fibers to the matrix. In addition to glass fibers, carbon fibers, e.g., epoxy resin-sized carbon fibers have been used for reinforcement. ... 

Another very popular tetrafunctional resin, tetraglyddylmethylenedianiline (TGMDA) (e.g., Ciba s MY720), has found widespread use in many prepreg systems used with carbon fiber composites and is available in different grades of purity. 

Aker Finnyards Oy used a foam sandwich structure, utilizing an epoxy resin infusion process with carbon fiber reinforcement to make the superstructure of a prototype air cushion vehicle. 

Giant Bicycles claims 17 years of experience in building carbon fiber bikes. The monocoque frames are built with carbon fiber/Kevlar/epoxy resin using a bladder molding technique. The majority of their frames are, however, built with Al, using carbon forks and seat posts. 

The degree to which carbon fibers reduce the coefficient of friction of thermoplastic resins is largely determined by the type of matrix resin used. Coefficient of friction of carbon fibers against steel is about 0.25 compared with 0.8 for glass fiber. Polymers reinforced with carbon fibers cause only about one-tenth of the wear on a relatively soft counterface such as mild steel than glass fiber-reinforced plastics. 

Figure 4.2. Variation of flexural strength with carbon fiber content for phenolic resin filled with pristine ( ), nitric acid modified- (O) and coupling agent treated- (a) SCFs [21]...

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