What You Should Know About Nylon And Polyester

Nylon Overview

Nylon is a group of synthetic polymers known as thermoplastics or aliphatic polyamides, which are derived from petroleum. It was originally manufactured as an alternative to silk, but its first commercial application was for toothbrush bristles in 1938 followed by women’s stockings in 1940.

During WWII, nylon was used extensively by the military and was difficult to obtain by the general public. Today, nylon remains one of the most commonly used fabrics in the world, second only to cotton. Also, being fabric, nylon can be condensed into a hard but flexible solid to be used for mechanical parts, gears, hair combs and other items.

Nylon is made through a chemical reaction in a process known as ring-opening polymerization. The molecules of the raw materials from which nylon is made are in ring form. But a chemical reaction, usually between adipoyl chloride and hexamethylene diamine causes the rings to open and flatten into curly strings that bond to one another. When nylon is stretched, the fibers become thin and smooth yet retain their strength.

Advantages of Nylon: Highly elastic, Durable and abrasion resistant, Resilient, Water resistant, Mold and mildew resistant, Stain resistant, Easily cleaned

Disadvantages of Nylon: Fades easily in sunlight, Environmentally unfriendly, not recyclable, Overly shiny appearance, May generate static electricity


Polyester Overview

Polyester is a term for a group of synthetic compounds that can be woven or knitted into fabric.

The most common form of polyester to be used as fabric is polyethylene terephthalate (PET), which is also used to create several types of plastic bottles.

Polyester was first produced in the U.K. in the early 1940s, and by the mid-1950s, it had already become a popular textile around the world. Today, polyester is used to manufacture a variety of products, including textiles, belts, furniture, insulation, padding, tarps and glossy finishes for hardwoods.

Like nylon, polyester is created through a chemical process involving a chain reaction. But the reaction occurs between mono ethylene glycol, purified terephthalic acid (PTA) and dimethyl terephthalate (DMT) to create bis terephthalate. When bis terephthalate is heated, it turns into PET, which is highly malleable and can be formed into long, thin and unbroken fibers.

Advantages of Polyester: Durable and abrasion resistant, Resists water, dries quickly, Resists stretching and shrinking, Mold and mildew resistant, Holds color well, resists fading, Easy to clean, may be dry cleaned, Recyclable

Disadvantages of Polyester: Non-breathable, Oils may stain


Nylon vs. Polyester

Nylon and polyester are very similar materials, and both may be used to manufacture various bags. Because of this similarity, the material that is best suited for bags is largely dependent upon the buyer’s personal preferences and the specific type of nylon and polyester that is used.

Nylon, polyester, and other fabrics are commonly differentiated through a unit of measure known as the denier (D, DEN). The denier measurement denotes linear mass density, which can be used to determine its strength when compared to the same type of material. While nylon has a lower denier thickness than polyester does, it is inherently stronger than polyester on a weight-for-weight basis. However, since polyester is a finer thread, it can be woven with a higher thread count to strengthen the finished product.

Of the two materials, nylon is the stronger, and it is more stretchable than polyester is. This stretchability occurs because nylon absorbs a small amount of water while polyester does not absorb any. Because of the water absorption, nylon does not hold dye well, and it tends to fade quickly when exposed to the sun whereas dyes bond strongly to polyester and are unaffected by UV radiation. This also means that nylon takes longer to dry than polyester does.