Degradation Fiber reinforcement

Table 13 Mechanical Properties of Flax Fiber Reinforced Biologically Degradable Polymers (BDG) [72]...

Whichever application of natural fiber or natural fiber-reinforced plastics will be used depends on the different environmental conditions, which are likely to add to the aging and degrading effects. On the other hand, such effects are often desirable, as is the case with com-... 

Fiber-reinforced plastics have varying degrees of resistance to adverse environments such as moisture, alkali, acid, and other chemicals. The degree of resistance depends on the fiber-resin system. Moisture absorption and chemical infiltration will be different for different fiber-resin systems. The degradation of composite materials may result from several factors ... 

Braun, U., Schartel, B., Fichera, M.A., and Jager, C. 2007. Flame retardancy mechanism of aluminum phosphinate in combination with melamine polyphosphate and zinc borate in glass-fiber reinforced polyamide 6,6. Polym. Degradation Stab., 92, 1528-1545. 

Unsaturated polyesters (UPs) crosslinked with styrene are often used as a matrix of fiber reinforced plastics. Several reports treated the degradation of the crosslinked UPs with high temperature treatment in water (1,2), acetic acid (5), alcohols including glycols (4,5), and amines (6), often in the presence of catalysts. In these literatures, recovery of polymeric materials from the crosslinked UPs was not a main objective. However, in case we can hydrolyze polyester chains selectively, linear polystyrene derivatives can be obtained as recycled materials. 

With the analysis embodied in Fig. 12, the formation of carbon fiber reinforced Si3N4 matrix materials by directed metal oxidation of molten silicon can also be described. To avoid fiber degradation during processing, the fiber should, ideally, be thermodynamically stable with respect to... 

Degradation of Nylon 6,6 and Glass Fiber Reinforced Nylon 6,6 by Aqueous Solutions of Ethylene Glycol and Calcium Chloride... 

Wider use of fiber-reinforced ceramic matrix composites for high temperature structural applications is hindered by several factors including (1) absence of a low cost, thermally stable fiber, (2) decrease in toughness caused by oxidation of the commonly used carbon and boron nitride fiber-matrix interface coatings, and (3) composite fabrication (consolidation) processes that are expensive or degrade the fiber. This chapter addresses how these shortcomings may be overcome by CVD and chemical vapor infiltration (CVI). Much of this chapter is based on recent experimental research at Georgia Tech. 

Fig4. shows the microstructures of the fracture surfaces. Some holes can be observed in both composites as a result of the fibers-pull-out, however, the lengths of the pulled-out fibers are very short. Compared to the nitridation temperature of 1800°C, the carbonization temperature of carbon fibers in the preparation process is relatively low, therefore, in the nitridation process, some damages may be done to the fibers and lead to the degradation in the strengths of fiber reinforcements and result in the low strength of composites. Some phases with layered structures can also be observed in the miciostructures of composite with boron, which corresponds to h-BN in situ formed in the nitridation process. When the cracks propagate to h-BN, they will deflect. 

Degradation and Flammability Behavior of Biofiber Composites and Biofiber/Glass Fiber Reinforced Polypropylene Hybrid Composites... 

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