The key difference between polyacrylates and polyesters is that polyacrylates contain acrylic acid repeating units, whereas polyester contains repeating ester units.
Polyacrylates and polyesters are polymer materials with a large number of repeating units. They differ from each other according to the type of repeating unit, also leading to different physical and chemical properties. The monomer for polyacrylates is acrylic acid. There are two monomers that make up the structure of polyester; the monomers for polyester are carboxylic acids and alcohols.
CONTENTS
1. Overview and Key Difference
2. What are Polyacrylates
3. What are Polyesters
4. Side by Side Comparison – Polyacrylates vs Polyesters in Tabular Form
5. Summary
What are Polyacrylates?
The term polyacrylate refers to a polymer material containing acrylate repeating units. It is a type of synthetic resin. And, it is made by polymerization of acrylic esters. Thus, the synonyms for polyacrylates are acrylic polymers and acrylics. Furthermore, the acrylate monomers have the general structure of acrylic acid. There is a carboxyl group and a vinyl group. The carboxylic acid group is usually an ester end or a nitrile end. In addition to that, there are derivatives of acrylates such as methyl methacrylates.
Figure 01: The Chemical Structure of Acrylic Acid
Moreover, this material is important because of its transparent appearance, resistance to breakage, elasticity, etc. There are many applications of polyacrylates. For example, these polymers are useful ingredients in paints as water-borne coatings and binders. Also, this polymer is used in the production of acrylic paint, acrylic fibre, thickeners such as sodium polyacrylate, acrylic resin, super glue, etc.
What are Polyesters?
Polyester is a group of long-chain polymers containing ester groups in the main chain. Polyesters are chemically composed 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, which forms esters, causes the formation of a polyester.
Figure 02: A Cloth made of Polyester
Moreover, polyesters are formed from the condensation reaction between dicarboxylic acids and alcohols (diols). Also, there are two main types of polyesters as saturated polyesters and unsaturated polyesters. Saturated polyesters are composed of saturated backbones. Since they are saturated, these polyesters are less or not reactive. Meanwhile, unsaturated polyesters are composed of vinyl unsaturation. Therefore, these polyester materials are very reactive.
Furthermore, polyester fibres are extremely strong and durable. It is because polyesters are often resistant to chemicals, stretching, shrinking, etc. The most common applications of polyester are in the textile industry, the food industry (for food packaging), etc.
What is the Difference Between Polyacrylates and Polyesters?
Polyacrylates and polyesters are polymer materials containing a large number of repeating units. The key difference between polyacrylates and polyesters is that polyacrylates contain acrylic acid repeating units, whereas polyester contains repeating ester units. Furthermore, the monomer for polyacrylates is acrylic acid. In contrast, there are two monomers that make up the structure of polyester; the monomers for polyester are carboxylic acids and alcohols.
Moreover, polyacrylate contains a carboxyl group and a vinyl group while polyester contains a dicarboxylic group and alcohol group.
The following table summarizes the difference between polyacrylates and polyesters.
Summary – Polyacrylates vs Polyesters
Polyacrylates and polyesters are polymer materials containing a large number of repeating units. The key difference between polyacrylates and polyesters is that polyacrylates contain the acrylic acid repeating units, whereas polyester contains repeating ester units. The monomer for polyacrylates is acrylic acid. There are two monomers that make up the structure of polyester; the monomers for polyester are carboxylic acids and alcohols.
Reference:
1. “Polyacrylate.” Encyclopædia Britannica, Encyclopædia Britannica, Inc., 25 Sept. 2019, Available here.
Image Courtesy:
1. “Acrylic acid” By User:Bryan Derksen – Own work (Public Domain) via Commons Wikimedia
2. “Purple Polyester Fabric” By shaireproductions.com (CC BY 2.0) via Flickr