Nylon 6/6 is a general-purpose nylon that can be both molded and extruded. Nylon 6/6 has good mechanical properties and wear resistance. It has a much higher melting point and higher intermittent use temperature than cast Nylon 6. It is easy to dye. Once dyed, it exhibits superior colorfastness and is less susceptible to fading from sunlight and ozone and to yellowing from nitrous oxide. It is frequently used when a low cost, high mechanical strength, rigid and stable material is required. It is one of the most popular plastics available. Nylon 6 is much more popular in Europe while Nylon 6/6 is hugely popular in the USA. Nylon can also be molded quickly and in very thin sections, as it loses its viscosity to a remarkable degree when molded.Nylon does not withstand moisture and watery environments well.
Nylon 4/6 is primarily used in higher temperature ranges where stiffness, creep resistance, continuous heat stability and fatigue strength are required. Therefore Nylon 46 is suitable for high quality applications in plant engineering, the electrical industry and in automotive applications under the hood. It is more expensive than Nylon 6/6 but it is also a vastly superior material which withstands water much better than Nylon 6/6 does.