Nylon (Polyamides)
Nylons (polyamides) were the first of the thermoplastic engineering resins. These crystalline plastics are available in many compositions, ranging from molding and extrusion materials to solution and fluidized bed coatings and casting resins. Nylon 6/6, the most widely used of the nylon plastics, is available in a number of formulations for molding and extrusion. Other general types are Nylon 6/10 and Nylon 6/l2. These are higher priced materials, used where greater dimensional stability is required.
The crystalline structure of nylons, which can be controlled to some degree in processing, affects stiffness, strength, and heat resistance, but at the sacrifice of tensile strength and stiffness. Nylons that have not been compounded with UV stabilizer are sensitive to ultraviolet light. These compounds should not be used for extended outdoor service. Carbon-black is the most effective of the UV stabilizers. These additives also increase tensile strength and hardness and decrease ductility and toughness slightly.
Applications
The automotive industry is the largest user of nylon resins. Good mechanical properties and resistance to heat and fuels make these materials suitable for mechanical and electrical hardware and under-the-hood components.
- Timing Sprockets
- Speedometer Gears
- Coding Fans
- Wire Connectors
- Windshield Wiper Parts
- Door-Latch Hardware
- Molded Fender Extensions
- Steering-Column Lock Housings
- Brake Fluid Reservoirs
- Bearings
- Business Machines
- Appliances
- Industrial Equipment
Low friction, good abrasion resistance, and the ability to operate without lubrication qualify the nylons for such applications. Although lubrication improves the performance of nylon bearings and wear surfaces, only intermittent lubrication is required.
Cast Nylons
Applications for cast nylons are mostly industrial equipment. These include mechanical components.
- Large Rollers
- Bearings
- Gears
- Cams
- Sheaves