PA66-GF Glass-Filled Nylon 66: Properties & Data

About this material

Glass fiber-reinforced polyamide (PA66+GF) is a composite material made from polyamide 66 (PA66) and reinforced with glass fibers for improved mechanical properties. Polyamide 66 is a type of nylon that is manufactured through the polycondensation of two monomers: hexamethylenediamine and adipic acid, each containing six carbon atoms—hence the PA66 name.

Strength and heat

The addition of glass fibers increases PA66’s tensile strength from 75 MPa to 180 MPa or more when the composite contains 30% glass fiber, enabling its use in load-bearing applications. Flexural strength is enhanced compared with PA66; for example, a 30% glass fiber content translates to a flexural strength of roughly 250 MPa. Furthermore, impact resistance and durability are improved, although the composite becomes more brittle compared to the polymer alone. PA66+GF is suitable for applications involving friction or stress, as the composite exhibits superior hardness with improved surface durability and wear resistance.

While glass fiber reinforcements do not alter the melting point of PA66 dramatically, they significantly improve the heat deflection temperature, i.e., the temperature at which the material begins to deform under load. This property translates to improved heat resistance compared with PA66 alone. Although PA66+GF remains an insulator, its thermal conductivity is enhanced. Dimensional stability is also improved due to a lower coefficient of thermal expansion, meaning that the material undergoes expansion to a lesser extent with temperature changes as glass fiber content increases.

Chemicals, water and electrical properties

The excellent chemical resistance of PA66 to oils, fuels, and solvents is retained in PA66+GF. However, the composite is susceptible to degradation by strong acids and bases, which can damage both the polyamide matrix and the glass fibers. The addition of glass fiber also improves one significant limitation of PA66: moisture absorption. Although PA66 tends to absorb moisture, which can affect its mechanical properties, PA66+GF demonstrates reduced moisture absorption, though it does not become moisture-resistant.

Although glass fiber-reinforced PA66 resists electrical conductivity, the exact grade should be checked for high-voltage applications where insulation is required.

Sustainability

The production process of PA66 is energy-intensive, a process that becomes even more demanding when incorporating glass fibers. PA66 is a downstream product of the petrochemical industry, and extracting glass fibers from raw materials, such as silica sand or limestone, also has environmental impacts. Like most synthetic polymers, PA66+GF is non-biodegradable, and as such, proper waste management is key to limiting associated pollution.

Reducing PA66+GF’s carbon footprint poses challenges, as recycling the material involves technical difficulties. Glass fibers can degrade during recycling, resulting in products that demonstrate diminished mechanical properties. Mechanical recycling may also damage the matrix and glass fibers. Finally, while in theory, chemical recycling of the composite into PA66 and GF can be achieved, the associated costs and technical limitations make this a complex process and impede large-scale implementation.

History

Discovered and brought to the mainstream market between the 1930s and 1940s by DuPont, polyamide 66 (PA66 or nylon 66) quickly became a popular choice for mass-produced goods due to its durability, chemical resistance, and versatility as a synthetic plastic. As demand for high-strength, heat-resistant, and lightweight materials grew, composites such as PA66+GF were created by adding glass fiber reinforcements to polyamide-type polymers. The characteristics of PA66+GF can be fine-tuned to meet end-product requirements by varying the glass fiber content (e.g., 10%, 30%, 50%) and using specific compounding methods.

Discover our Nylon PA 66 / 50% Glass Fibre Reinforced collection, featuring Countersunk Cross Head Bolts. Derived from nylon 66 and glass fibers, this composite material offers improved tensile strength and deflection temperature compared to standard nylon.