High temperature applications glass composites

Epoxy-phenolic adhesives were developed primarily for bonding metal joints in high-temperature applications. Their first major application was to join major aircraft components. They are also commonly used for bonding glass, ceramics, and phenolic composites. Because of their relatively good flow properties, epoxy phenolics are also used for bonding honeycomb sandwich composites. 

Polyimides have been used up to 100 h at 600°F (315.6°C). They have been used as a transparent head cover for fire fighters and as excellent flame- and high-temperature-resistant foams, which can be used as structurally stable insulation materials at high temperatures. Polyimide/glass fiber composites have many uses in the electronics and aerospace industries and in other high-performance applications. 

It is well established that the addition of rubber or thermoplastic to the resin or rubber coating of the glass fabric prior to lamination improves the impact resistance in glass/epoxy laminates [189,190], Thermoplastic additions are more lucrative when considering their high-temperature applications and the compromises that are made in mechanical properties other than toughness in rubber-modified glass/epoxy composites. 

Forsdyke, K.L. (1984) Phenolic resin composites for fire and high temperature applications, in Fibre Reinforced Composites PRI, London. Sundaram, S. (1990) Development of phenolic compatible glass reinforcements for the growing Indian market. Popular Plastic Packaging 35, 17-22. 

The most widely used and least expensive polymer resins are the polyesters and vinyl esters. These matrix materials are used primarily for glass fiber-reinforced composites. A large number of resin formulations provide a wide range of properties for these polymers. The epoxies are more expensive and, in addition to commercial applications, are also used extensively in PMCs for aerospace applications they have better mechanical properties and resistance to moisture than the polyesters and vinyl resins. For high-temperature applications, polyimide resins are employed their continuous-use, upper-temperature limit is approximately 230°C (450 F). Finally, high-temperature thermoplastic resins offer the potential to be used in future aerospace applications such materials include polyetheretherketone (PEEK), poly(phenylene sulfide) (PPS), and polyetherimide (PEI). 

An interesting application of sprayed aluminium is for resistance to high-temperature oxidation up to 900°C. The article is grit-blasted and aluminium sprayed, usually to a thickness of 0-008 in (0-2 mm). It is then treated with a sealing composition which may be bitumen or water-glass, and is diffusion annealed in a furnace at 850 C for approximately 30 min. The final coating... 

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