Difference Between Nylon and Polyester

Key difference - nylon vs. polyester

Nylon and polyester are polymers . A polymer is a macromolecule made up of a large number of monomers . Monomers covalently each bind to form a polymer molecule. The properties of a polymer depend mainly on the type and arrangement of the monomers present in the polymer molecule. Since there are thousands of natural polymers and synthetic polymers, these macromolecules can be grouped according to different properties. The main difference between them is that nylon is essentially composed of nitrogen atoms in structure while polyester has no nitrogen atoms.

Key areas covered

1. What is nylon - definition, properties and uses 2. What is polyester - definition, properties and uses 3. What are the Similarities Between Nylon and Polyester - Overview of Common Features 4. What is the Difference Between Nylon and Polyester - Comparison the main differences

Key Terms: Monomer, Nylon, Polyester, Polymer, Saturated Polyester, Unsaturated Polyester

What is nylon

Nylon is a common name for a class of polymer molecules made up of polyamides. This group of polymers includes plastics. Because of their thermal properties, they are called thermoplastics . Some of the members of this group are listed below.

Nylon 6
Nylon 6.6
Nylon 6.8
Nylon 6.10

Due to the synthesis method, nylons belong to the condensation polymers. Nylon polymers are made by condensation polymerization . Monomers that are involved in the manufacture of nylon are diamines and dicarboxylic acids. The condensation polymerization of these two monomers forms peptide bonds . A water molecule is created as a by-product per peptide bond.

Most nylon shapes consist of symmetrical backbones and are semi-crystalline. This makes nylons very good fibers. The name of the nylon form is given according to the number of carbon atoms present in the diamine and dicarboxylic acid monomers. For example, in nylon 6,6 there are six carbon atoms in the dicarboxylic acid and six carbon atoms in the diamine.

Figure 1: Structure of nylon 6 and nylon 6,6

In general, nylons are sturdy materials. This material has good chemical and thermal resistance. Nylons can be used in high temperature environments. The maximum temperature in which nylon can be used is 185 ^o C. The glass transition temperature of nylon is about 45 ^o C. The glass transition temperature of a polymer is the temperature at which the polymer transitions from a hard, glassy material to a soft, rubbery material.

Nylon is used in the manufacture of films and fibers. It is also used as a molding compound. Apart from that, nylons can be mixed with other plastics to improve their performance. Nylon resins are used in the automotive industry. It is used as packaging material where an oxygen barrier is required for food packaging.

What is polyester

Polyester is a common name used to describe long chain polymers made up of ester groups in the main chain. Chemically, polyesters consist of at least 85% by weight of an ester and a dihydric alcohol and a terephthalic acid. In other words, the reaction between carboxylic acids and alcohols to form esters results in the formation of a polyester.

Polyesters arise from the condensation reaction between dicarboxylic acids and alcohols (diols). There are mainly two types of polyesters, saturated polyesters and unsaturated polyesters. Saturated polyesters consist of saturated main chains. Because they are saturated, these polyesters are less or non-reactive. Unsaturated polyesters are made up of vinyl unsaturation. Therefore these polyester materials are very reactive.

Figure 2: Polyester material

Polyester fibers are extremely strong. It's a durable material. This is because polyesters are often resistant to chemicals, stretching, shrinking, etc. The most common uses of polyester are in the textile industry, food industry (for food packaging), etc.

Similarities Between Nylon and Polyester

Both are polymer materials.
Both are made by condensation polymerization.
Both synthesis mechanisms produce water molecules as by-products.
Both are very important in various industries.

definition

Nylon: Nylon is a common name for a class of polymer molecules made up of polyamides.

Polyester: Polyester is a common name used to describe long chain polymers made up of ester groups in the main chain.

Chemical name

Nylon: Nylons are also known as polyamides due to the presence of amide groups.

Polyester: Polyesters are also called polyethylene terephthalate (PET).

Monomers

Nylon: The monomers involved in making nylon are diamines and dicarboxylic acids.

Polyester: The monomers involved in polyester production are dicarboxylic acids and diols.

Nitrogen atoms

Nylon: Nylon polymers are essentially made up of nitrogen atoms.

Polyester: Polyesters have no nitrogen atoms in their chemical structure.

diploma

Nylons and polyesters are very useful polymer materials in the industry. Although these materials are sometimes used for the same purpose because of some similar properties, they have different chemical structures. The main difference between nylon and polyesters is that nylon is essentially composed of nitrogen atoms in structure while polyester has no nitrogen atoms.

References:

1. "Nylons." The Polymer Science Learning Center, available here. 2. "What is polyester?" What is polyester, available here .3. Lazonby, John. "Polyester." The Essential Chemical Industry online, available here .

Image courtesy:

1. “Nylon6 and Nylon 66” by Michael Ströck (mstroeck) at en.wikipedia - transferred from en.wikipedia (CC BY-SA 3.0) via Commons Wikimedia 2. “Polyester scarf clothing cards” (Public Domain) via Pixabay