Phenolic matrix composite

Figure 4. Nozzle of the booster rockets of the European satellite launcher Ariane V having an outer diameter of 2.8 m, an inner diameter of 90 cm, and an overall weight of 6 metric tons. The nozzle is fabricated with C/C and carbon fiber/phenolic matrix composites courtesy SEP division de SNECMA.

S. Wang, S. Adanur and B. Z. Jang, Mechanical and thermo-mechanical failure mechanism analysis of fiber/filler reinforced phenolic matrix composites . Composites Part B, 1997, 28B, 4, 215-231. 

Carbon-matrix composites, 26 751 Carbon microbeads, phenolic resins in,... 

One typical example of carbon/carbon composite plates is that made by Oak Ridge National Laboratory (ORNL) in the United States [12]. The composite preform was fabricafed by a slurry-molding process from fhe mixed slurry befween short carbon fibers (graphite fibers were also added in some sample plates) and fhe phenolic resin. The mass rafio between fiber reinforcement and phenolic matrix is 4 3. The phenolic matrix improves the mechanical properties and dimensional stability of the plate. A subsequent vacuum molding process was utilized to fabricate composite plates and fluid fields with relatively high resolution (Figure 5.3, [11]). 

Most structural PMCs consist of a relatively soft matrix, such as a thermosetting plastic of polyester, phenolic, or epoxy, sometimes referred to as resin-matrix composites. Some typical polymers used as matrices in PMCs are listed in Table 1.28. The list of metals used in MMCs is much shorter. Aluminum, magnesium, titanium, and iron- and nickel-based alloys are the most common (see Table 1.29). These metals are typically utilized due to their combination of low density and good mechanical properties. Matrix materials for CMCs generally fall into fonr categories glass ceramics like lithium aluminosilicate oxide ceramics like aluminnm oxide (alnmina) and mullite nitride ceramics such as silicon nitride and carbide ceramics such as silicon carbide. 

Carbon Composites. Cermet friction materials tend to be heavy, thus making the brake system less energy-efficient. Compared with cermets, carbon (or graphite) is a thermally stable material of low density and reasonably high specific heat. A combination of these properties makes carbon attractive as a brake material and several companies are manufacturing carbon fiber—reinforced carbon-matrix composites, which are used primarily for aircraft brakes and race cars (16). Carbon composites usually consist of three types of carbon carbon in the fibrous form (see Carbon FIBERS), carbon resulting from the controlled pyrolysis of the resin (usually phenolic-based), and carbon from chemical vapor deposition (CVD) filling the pores (16). 

Lavik, M.T, and Hopkins, V., Development of Self-Lubricating Composites Utilising Carbonised Phenolic Matrix, AFML-TR-75-175-PT. (1975). 

S. J. Park and Y. S. Jang, Interfocial characteristics and fiacture toughness of electrolytically Ni-plated carbon fiber-reinforced phenolic resin Matrix composites, J. Colloid Interface Sci. 237 (2001) pp. 91-97. 

Wijdenes and Geomini (170) examined the effects of the phenolic resin composition, its molecular weight distribution, solvent composition, and prebake temperature on the interfacial layer formation. They found that combined use of poly(p-vinylphenol) (structure 3.10) as matrix resin and cyclohexanone as the casting solvent in the diazoquinone resist formulation minimizes mixing of the two layers and yields a capped PCM structure without any plasma treatment. 

Keywords. Cyanate ester, Polycyanurates, Phenolic-triazine, Polymer matrix composite, Cure kinetics, Polymer blends, Cyanate-epoxy blend, Bismaleimide-triazine resins, Aerospace structure... 

The matrix material used in polymer-based composites can either be thermoset (epoxies, phenolics) or thermoplastic resins (low density polyethylene, high density polyethylene, polypropylene, nylon, acrylics). The filler or reinforcing agent can be chosen according to the desired properties. The properties of polymer matrix composites are determined by properties, orientation and concentration of fibers and properties of matrix. 

Bertrand and co-workers [100] have described the use of ToF-SIMS for examining the interface region of a Hercules AS-4 carbon fiber-polystyrene matrix composite. Triple focussing ToF-SIMS is described by Wayne [101]. Betrand et a/[102] have used ToF-SIMS to elicit chemical information on the interfacial area of carbon fiber. Weng et al [103] used ToF-SIMS in conjunction with XPS to show that the size on Hercules AS-4 contains at least four different compounds—polydimethylsiloxane, dialkyl phthalates, glyceryl monostearate and phenolic antioxidants. 

Thermoset composites are made up of thermoset resin-like polyester epoxy and phenol-formaldehyde resin composites with varying fiber volume fractions and fiber length were prepared by following one of the techniques. Among polyester epoxy and phenol-formaldehyde composites, a phenolic-type resin performed as a better matrix than epoxy and polyester resins with respect to tensile and flexural properties due to the high interfacial bonding in phenolic composites [58,59,100]. 

In another study, Bafekipour and et al. [60] designed and fabricated functionally graded carbon nanofiber-phenolic nanocomposites (FGN) using four different gradient patterns and the same overall carbon nanofiber (CNF) content and geometry. The composition across the thickness of the samples was controlled in eight 600-mm-thick layers with clear interlayer boundaries. They observed that the incorporation of CNF into the phenolic matrix increased the thermal conductivity of the resin. For example, the thermal conductivity of the matrix increased 28.1, 49.5 and 90.4 % with the incorporation of 2, 4 and 16 wt% CNF, at room temperature, respectively. The authors attributed this thermal conductivity enhancement in the phenolic matrix is due to the formation of inter-connected mesh of CNFs. 

Koo et al. [71] compared the ablative properties of carbon phenolic composite (MX-4926) to laboratory produced carbon nanofibers (CNFs)/phenolic nanocomposites (CNF-NRAMs). Three CNF loadings, namely 20 %, 24 % and 28 wt% were dispersed in the phenolic matrix without rayon-carbon fiber reinforcement. A subscale rocket motor (heat flux 1140 W/cm ) was used to study the ablation and insulation characteristics of the ablatives. According to the experimental results, when compared to the MX-4926, all the CNF-NRAMs exhibited lower ablation rates and the lower maximum backside heat-soaked temperature increase. Peak... 

Phenolic resins exhibit excellent dimensional stability with a constant use temperature range of 180-200 °C, excellent resistance to chemicals, moisture, and heat and favorable behaviour against fire and smoke. The predominant consideration in the use of phenolic resins as a matrix resin in fibre-reinforced composites is fire behaviour. Phenolic-based composites perform better under fire conditions compared with epoxy- or vinyl ester-based composites. This is due to their delayed ignitability coupled with low heat release, low smoke evolution with little or no toxic gas emission, and capability to provide significant strength retention (70%)... 

Though many researchers think that, in the future, thermoplastic matrix composites will gain popularity, there is stiU a long way to go before they achieve widespread use in the structural field. The most important thermosetting plastic matrices (resins) are polyester, epoxy, phenolic, and silicone. 

Carbon-plastic matrix compositions including continuous phases of PTFE, or phenol-furfural are of interest as potential seal materials. Experiments in liquid nitrogen and liquid hydrogen showed good wear and friction properties for those materials. The phenol-furfural composition also had good wear and fric-... 

The search for alternatives to raw materials derived from fossil fuels has accelerated in recent decades and has reached the area of polymer matrix composites. In the case of phenolic matrices, several alternatives have been considered, particularly for the phenolic component. 

MWNTs have been used as dispersed CNTs and network CNTs as reinforcements of phenolic matrices. Composite phenolic-dispersed CNTs were fabricated through the melt mixing method, which may lead to the agglomeration of CNTs in the matrix and introduce defects in composites. The infiltration of the resin into the network CNT generated composites with better mechanical properties when compared to the dispersed CNTs because the CNTs in the network are longer and contain fewer agglomerates and defects (Tai et al, 2004). 

Ablation resistance is an important property of composites, with thinner ablative structures desired to reduce the overall weight of aerospace systems. Phenolic resins easily char during endothermic pyrolysis, leading to the application of phenolic composites as ablative materials for rocket nozzles (Srikanth et al, 2010). A phenolic matrix with a high content of carbon nanofibers (CNFs) was demonstrated to be highly appropriate for rocket nozzle applications (Yoonessi et al., 2008). 

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