Boron-epoxy plastics

Fiber-reinforced composite materials such as boron-epoxy and graphite-epoxy are usually treated as linear elastic materials because the essentially linear elastic fibers provide the majority of the strength and stiffness. Refinement of that approximation requires consideration of some form of plasticity, viscoelasticity, or both (viscoplasticity). Very little work has been done to implement those models or idealizations of composite material behavior in structural applications. 

Boron-epoxy composite n. A composite in which boron fibers are embedded in an epoxy matrix. Modulus is about 200 GPa, tensile strength about 1.6 GPa, rising with fiber content. The combination of high specific modulus and high specific strength has made these composites attractive for aerospace vehicles in spite of their high cost. Harper CA (ed) (2002) Handbook of plastics, elastomers and composites, 4th edn. McGraw-Hill, New York. 

Leecure B. [Leqroxy Plastics] Boron ttifluoride-based epoxy curing agents/ hardeners. 

EPOXY-3-BUTOXY PROPANE (2426-08-6) C7H14O2 Highly flammable and peroxidizable liquid. Forms explosive mixture with air (flash point 130 F/54°C). Air and light form unstable and explosive peroxides. Violent reaction with strong oxidizers may cause fire and explosions acryl and acid halides. Incompatible with acids, boron trifluoride. Strong caustics may cause polymerization. Attacks some plastics and rubber. On small fires, use dry chemical powder (such as Purple-K-Powder), foam, or COj extinguishers. 

Fibre reinforced plastics. The most wide-spread reinforcement is glass fibre as roving, chopped strand mat, fabric, etc. The most usual matrix materials are unsaturated polyesters and epoxy resins as thermosets. In glass fibre reinforced thermoplastics (e. g. ABS, PA, PPO), the length of the glass fibres is 1 to 3 mm. Other reinforcing fibres are aramide, asbestos, boron, carbon, etc. 

A list of materials regarded as high-performance polymers (Table 17.10) overlaps the list of Table 17.9 to some extent, but also includes thermosets such as epoxy, phenolic, and silicone molding resins. As with most molded plastics, high-tanperature performance is enhanced by reinforcement with glass, boron, or carbon or aramid fibers. The thermosets are seldom used without reinforcement. Several are inclnded in Figures 17.6 and 17.7. 

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