Differences between Nylon and Polyester

Nylon vs. Polyester

Nylon and polyester are both synthetic polymers widely used in the textile industry and for various industrial applications. Both materials are derived from petroleum. Nylon, a polyamide, was first synthesized in the 1930s, while polyester, a category of polymers containing the ester functional group, was introduced in the 1940s. Their production processes share similarities, involving the melting of plastic pellets and extruding them to form fibers.

Comparison Table

Category	Nylon	Polyester
Durability & Strength	Generally stronger and more resistant to abrasion. It possesses high tensile strength.	Durable, but typically not as strong as nylon.
Elasticity	Higher elasticity, can stretch significantly without losing its shape.	Less elastic than nylon, providing more stability.
Water Resistance	More absorbent than polyester, which can increase drying time.	Hydrophobic, meaning it repels water and dries quickly.
UV Resistance	Can be susceptible to fading and degradation from sunlight.	More resistant to UV rays, making it suitable for outdoor use.
Feel and Texture	Typically has a softer, smoother, and silkier feel.	Can have a slightly rougher texture, though modern production has improved its softness.
Cost	More expensive to produce due to a more complex manufacturing process and higher raw material costs.	Generally less expensive and more budget-friendly.
Environmental Impact	Production is energy-intensive and creates nitrous oxide, a potent greenhouse gas. Recycling is less common and can be more expensive than producing new nylon.	Production requires large amounts of water for cooling and can be a source of contamination. It is more efficiently recycled than nylon.
Common Uses	Ropes, parachutes, carpets, swimwear, and activewear. Also used in industrial applications like tire cords and seat belts.	Clothing, home furnishings, sails, and beverage bottles. Often used for sportswear due to its moisture-wicking properties.

Venn diagram comparing Differences between Nylon and Polyester

Production

The manufacturing process for both nylon and polyester involves polymerization, where monomers are chemically reacted to form long polymer chains. For nylon, this typically involves the reaction of a diamine with a dicarboxylic acid. The resulting molten polymer is then extruded through a spinneret, a device with many small holes, to form continuous filaments. These filaments are then stretched to increase their strength and elasticity before being wound onto bobbins.

Polyester production commonly uses polyethylene terephthalate (PET). The process starts by reacting ethylene glycol with terephthalic acid or dimethyl terephthalate at high temperatures. This creates a molten polymer that is extruded into strips, cooled, and cut into chips. These chips are then melted again and forced through a spinneret to create fibers, which are subsequently drawn and spun into yarn.

Environmental Considerations

Both nylon and polyester are derived from petrochemicals and are non-biodegradable, which raises environmental concerns. The production of nylon releases nitrous oxide, a significant greenhouse gas. Polyester manufacturing is water-intensive and can lead to water contamination.

Recycling is an option for both materials, helping to reduce their environmental footprint. Recycled polyester, often made from plastic bottles, requires less energy to produce than virgin polyester. Recycled nylon can be produced from materials like old fishing nets and carpets, diverting waste from landfills and oceans. However, the infrastructure for recycling nylon is less established and can be more costly than producing new material. Both recycled fabrics can shed microplastics during washing.