Unformatted text preview: Plastics *Properties and Applications *Light weight – specific gravities between 1.1 and 1.6 *Corrosion resistance – perform well in hostile, corrosive environment *Electrical resistance – used as insulating materials *Low thermal conductivity – good thermal insulators *Variety of optical properties – transparent, opaque and unlimited color range *Formability – cast, extruded, or molded at relatively low temperatures *Surface finish – excellent surface finishes obtainable *Comparatively low cost – generally low cost material and processing *Low energy requirements for production Plastics - Common Types or Families * Thermoplastics – long chains of primary bonded molecules with secondary van der Waals forces that weaken at elevated temperatures. Can be recycled. * Thermosets – highly cross-linked or three dimensional framework structure, strong covalent bonds, relatively high heat tolerance. Cannot be recycled Plastics *Additive Agents in Plastics – fillers, plasticizers, lubricants, coloring agents, stabilizers, antioxidants, flame...
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- Fall '07
- Polymer, Thermal insulation, relatively low temperatures, molding *Injection molding, molding *Transfer molding, low cost material