The key difference between polysulfone and polyethersulfone is that a polysulfone is a group of thermoplastic polymers consisting of repeating units with a sulfone group, whereas polyethersulfone is a group of thermoplastic polymers consisting of the subunit aryl-SO2-aryl pattern.
There are three major polysulfone types that are useful industrially: regular polysulfone (PSU), polyethersulfone (PES), and polyphenylene sulfone (PPSU). We can use these materials for applications in temperatures ranging from -100 to +200 degrees Celsius. They are also useful in electrical equipment, vehicle construction, and medical technology.
CONTENTS
1. Overview and Key Difference
2. What is Polysulfone
3. What is Polyethersulfone
4. Polysulfone vs Polyethersulfone in Tabular Form
5. Summary – Polysulfone vs Polyethersulfone
What is Polysulfone?
Polysulfone is a family of high-performance thermoplastics. These polymers are very important because of their toughness and stability at high temperatures. Polysulfones that are used technically consist of an aryl-SO2- aryl subunit. Since the cost is very high to obtain raw materials and process polysulfones, these materials are used in special applications, and often these are used as superior replacements for polycarbonates.
Figure 01: The Repeating Unit of Polysulfone
Polysulfone compounds are produced by polycondensation reaction of diphenoxide and bis(4-chlorophenyl)sulfone. In this reaction, the sulfone functional group activates the chloride groups toward substitution. Moreover, diphenoixde is produced in situ from diphenol and sodium hydroxide.
When considering the properties of polysulfone compounds, these are rigid, high-strength, and transparent materials that can be characterized by high strength and stiffness, and these properties are retained between -100 to 150 degrees Celsius. Furthermore, the glass transition temperature is between 190 and 230 degrees Celsius. The dimensional stability of polysulfones is high, and the size changes when it is exposed to boiling water or 150 degrees Celsius air or steam that generally falls below 0.1%.
Moreover, this material is highly resistant to mineral acids, alkali, and electrolytes in pH values that range from 2 to 13 and also resistant to oxidizing agents. Thus, we can use this material against bleach. Furthermore, polysulfones are resistant to surfactants and hydrocarbon oils, and low polar organic solvents.
What is Polyethersulfone?
Polyethersulfone (PES) is the second most widely used membrane material in the membrane bioreactor (MBR) that is used in the wastewater treatment process. Polyethersulfone has a chemical structure in which ether bonds and sulfone bonds are mainly linked with phenyl. The heat resistance of this material is intermediate between bisphenol A polysulfone and polyarylethersulfone.
This material has a higher melting point and thermal stability compared to other polymeric membranes by only 1% mass loss in the air under 400 degrees Celsius. Moreover, this material is more hydrophilic than polyvinylidene fluoride (PVDF) because of the molecular structure that can facilitate hydrogen bonding with water molecules. This, in turn, makes the higher volume of permeate to be attained using the PES membrane.
Polysulfone can be described as an amorphous, transparent, and pale amber high-performance thermoplastic material that is the most temperature-resistant and commercially available thermoplastic resin. Besides, it has a higher water absorption comparatively, and we can make stable solutions by choosing suitable solvents.
What is the Difference Between Polysulfone and Polyethersulfone?
Polysulfone is a large group of sulfone compounds, while polyethersulfone is also a member of this group. The key difference between polysulfone and polyethersulfone is that a polysulfone is a group of thermoplastic polymers consisting of repeating units with a sulfone group, whereas a polyethersulfone is a group of thermoplastic polymers consisting of the subunit aryl-SO2-aryl pattern.
The following table summarizes the difference between polysulfone and polyethersulfone.
Summary – Polysulfone vs Polyethersulfone
Polysulfone is a family of high-performance thermoplastics, while polyethersulfone is the second most widely used membrane material in the membrane bioreactor (MBR). The key difference between polysulfone and polyethersulfone is that a polysulfone is a group of thermoplastic polymers consisting of repeating units with a sulfone group, whereas polyethersulfone is a group of thermoplastic polymers consisting of the subunit aryl-SO2-aryl pattern.
Reference:
1. “Poly(Ether-Sulfone) Polymer.” An Overview | ScienceDirect Topics.
Image Courtesy:
1. “Polysulfone” By Leyo – Own work (Public Domain) via Commons Wikimedia