Aramid-silicone resin

A very tough 177-204 C versatile curing resin with a continuous service temperature range of -59 to 204 C, and short-term up to 232 C, and designed for RTM. Offers excellent compression properties after impact. Suitable for glass, carbon, aramid, silicon carbide and other fibre reinforcement. 

Additives used in final products Fillers antimony trioxide, aramid, barium sulfate, boron nitride, calcinated kaolin, carbon black, carbon fiber, glass fiber, glass spheres, mica, montmorillonite, talc, titanium dioxide, zinc borate Antistatics antimony-doped tin oxide, carbon nanotubes, polyaniline, polyisonaphthalene Antiblocking calcium carbonate, diatomaceous earth, silicone fluid, spherical silicone resin, synthetic silica Release calcium stearate, fluorine compounds, glycerol bistearate, pentaerythritol ester, silane modified silica, zinc stearate Slip spherical silica, silicone oil ... 

Typical fillers used for reduction of wear include PTFE, silicone, graphite powder, molybdenum disulfide, and aramid fibers. Good results were also reported with mica and zirconia combination. Figure 8.36 shows the effect of mica and mica in combination with zirconia on the wear resistance of an epoxy resin. ... 

The traditional TPS for launcher fairings and re-entry capsules consists of an external ablative insulation, fixed or bonded onto a metallic primary structure. Ablative materials are based on thermosets (phenolic and epoxy resins) or elastomers (ethylene-propylene and silicone rubbers) usually filled and reinforced with cork, cotton, glass, silica, quartz, carbon, silicon carbide, nylon and aramid in the form of powders, fibres, fabrics and felt (Table 2). 

Almost any continuous reinforcement can be used. The most commonly used is glass, both E and S, but carbon and aramid fibers are also used, and quartz, boron, ceramics and metal wire and strip have all been successfiilly applied. Latest developments include adaptation of the process for as3mimetrical products. Suitable resins include TS polyesters, epoxies, bismaleimides, polyimides, silicones, phenolics and thermoplastics. 

The common commercially available fibers used in composites are fiberglass, graphite (carbon), aramid, polyethylene, boron, silicon carbide, and other ceramics such as silicon nitride, alumina, and alumina silica. Many matrix choices are available, both thermosetting and thermoplastic. Each type has an impact on the processing technique, physical properties, and environmental resistance of the finished composite. The most common resin matrices include polyester, vinyl esters, epoxy, bismaleimides, polyimides, cyanate ester, and triazine. 

The low CTE of aramid non-woven reinforced prepreg and laminate provides a closer match to the CTE of the silicon chip. Depending on the type of resin and the resin and copper... 

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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