Difference Between Ethylene Glycol and Polyethylene Glycol

Main Difference

The main difference between the ethylene glycol and the polyethylene glycol is that there is a fixed value of molecular weight for the ethylene glycol whereas there is no fixed value of molecular weight for the polyethylene glycol.

Ethylene Glycolvs. Polyethylene Glycol

Although both the ethylene glycol and the polyethylene glycol have nearly similar names, they are different compounds from each other because of their general properties and their chemical structures. Ethylene glycol is an alcoholic compound. Polyethylene glycol, on the other hand, is a polyether compound. Because of the presence of –OH groups, both of these compounds are miscible with the water. Ethylene glycol is actually a simple linear molecule. Polyethylene glycol, on the flip side, is a polymeric material.

Ethylene glycol appears in a liquid state at room temperature. Polyethylene glycol, on the other side, may have different appearances which are based on its molecular weight. In order to produce the ethylene glycol, we use ethylene as the main chemical compound. On the other hand, when a reaction between ethylene oxide with water, the ethylene glycol or the ethylene glycol oligomers occurs, it produces the polyethylene glycol.

Comparison Chart

Ethylene GlycolPolyethylene Glycol
The alcoholic compounds which are colorless and odorless are called ethylene glycols.The compounds which are polyether, meaning that they have many ether groups are called polyethylene glycols.
General Formula
It has the general formula C2H6O2Polyethylene glycol has the general formula H−(O−CH2−CH2)n−OH
Morphology
Ethylene glycol is referred to as a simple linear molecule.Polyethylene glycol is referred to as a polymeric material.
Molecular Weight
Ethylene glycol has a fixed value of molecular weight which is about 62.07 g/mol.Polyethylene glycol does not have a fixed value of molecular weight. It is based on value of “n” in its general formula.
Production
Ethylene glycol is produced when a reaction takes place between the ethylene oxide and water.When a reaction takes place between ethylene oxide with water, the ethylene glycol oligomers or the ethylene glycol, it gives rise to polyethylene glycol.
Catalyst
Both acidic and basic catalysts are used for the production of ethylene glycol.Both acidic and basic catalysts are used for the production of polyethylene glycol.
Usage
Ethylene glycol is mostly used as an automotive antifreeze and for the manufacturing of polyester fibers.Polyethylene glycol has a lot of uses, including biological usage, industrial usage, medical usage, chemical usage, etc.
Toxicity
Ethylene glycol is considered a moderately toxic compound.It is not toxic.

What is Ethylene Glycol?

Ethylene glycol is referred to as a simple linear molecule, and its IUPAC name is ethane-1,2-diol. There is a fixed value of molecular weight for ethylene glycol. It is considered as a colorless, odorless and sweet-tasting viscous dihydroxy alcohol. It is moderately toxic if it gets ingested. Its molar mass is about 62.07 g/mol. It is considered a syrupy liquid at room temperature and pressure. It is mentioned as a viscous liquid with a boiling point of about 198 °C. Ethylene glycol is made up of two –OH groups. That is why this molecule may form hydrogen bonds with water molecules. So, it is miscible with water. It is sweet in taste.

The most common applications of ethylene glycol are that it is used as an automotive antifreeze and a raw material for the production of the polyester fibers. Automotive antifreeze is a liquid that is used in the cooling system of the combustion engine and the radiator of vehicles. It is also important in the manufacturing of resins, and low-freezing dynamites.

What is Polyethylene Glycol?

Polyethylene glycol is referred to as a polymeric material. It might have a mild odor. It does not have a fixed value of molecular weight for the polyethylene glycol. Its value is based on value of “n” in its general formula. Polyethylene glycol may have different forms based on its molecular weight. It is considered as an opaque liquid below a molecular weight of 700. It changes into a semisolid material at molecular weights between 700 to 900. It can be a white waxy solid, powder or flakes above a molecular weight of 900.

The final product that is obtained after the formation of polyethylene glycol provides a variety of polymer compounds with different molecular weights. But if we used oligomers or ethylene glycol in place of water, they will provide the final product with low polydispersity. The type of polymerization is based on the form of catalyst. It may be anionic or cationic polymerization. But anionic polymerization provides a low polydispersity. So, it is better. Furthermore, we may also use suspension polymerization. Polyethylene glycol plays an important role in biological, commercial, chemical, industrial and medical fields.

Key Differences

  1. The alcoholic compounds which are colorless and odorless are called ethylene glycols, whereas, the compounds which are polyether, meaning that they have many ether groups are called polyethylene glycols.
  2. Ethylene glycol has the general formula C2H6O2, on the other hand, polyethylene glycol has the general formula H−(O−CH2−CH2)n−OH.
  3. Ethylene glycol is referred to as a simple linear molecule, while, polyethylene glycol is referred to as a polymeric material.
  4. Ethylene glycol has a fixed value of molecular weight which is about 62.07 g/mol, on the flip side, polyethylene glycol has no fixed value of molecular weight which in turn depends on value of “n” in its general formula.
  5. Ethylene glycol is produced when a reaction takes place between the ethylene oxide and water, on the other side, when a reaction between ethylene oxide with water, the ethylene glycol oligomers or the ethylene glycol occurs it produces the polyethylene glycol.
  6. Ethylene glycol is mostly used as an automotive antifreeze, and for the manufacturing of the polyester fibers, on the other hand, polyethylene glycol has a lot of uses including the biological usage, the industrial usage, the medical usage, the chemical usage, etc.
  7. Ethylene glycol is considered a moderately toxic compound, on the flip side, polyethylene glycol is not a toxic compound.

Conclusion

The above discussion summarizes that the ethylene glycol and the polyethylene glycol both are very important molecules. The former is considered as a syrupy liquid at room temperature and comprises a fixed value for the molecular weight, whereas, the latter is considered as a solid material and comprises no fixed value for the molecular weight.

Harlon Moss

Harlon currently works as a quality moderator and content writer for Difference Wiki. He graduated from the University of California in 2010 with a degree in Computer Science. Follow him on Twitter @HarlonMoss

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