Urethane vs. Polyurethane
What is difference between Urethane and Polyurethane? We commonly use things made of urethane and polyurethane. But perhaps we do not know and many think that the only difference between these two is that the polyurethane is made of several urethane compounds. But in fact, it is not. There are many differences between these two compounds, infect below this post is all about the difference between Urethane and Polyurethane.
Difference between Urethane and Polyurethane
The first and biggest difference is the number of organic urethane units in both compounds. The polyurethane is made of a chain of joined organic urethane units. These polymers are formed by the polymerization reaction. The raw material used in the manufacture of polyurethane is polyesters, polyester, glycol and diisocyanate. The urethane has the functional group R1-O- (CO) NR2-R3. These are the acid esters and amides.
The polyurethane compounds are very rigid and hard. Its density is also greater. Due to these properties, polyurethane is used in the manufacture of insoles, solid plastic articles, sponges for bedding and other items such as printer rollers and gel cushions. Urethane is used in many insecticides. It is also used in certain veterinary medicines and in drugs for humans.
Urethane can be molded into different shapes and types for various purposes. The methods used for molding are compression, open forging and one-shot systems. There are different types of polyurethanes such as linear, injected, thermoplastic, cellular, foamed and spandex fibers.
The polyurethane has been tested and it has been found that its handling is not toxic under normal conditions. Urethane is toxic in small animals such as rats and rabbits. The compound has no smell but a sour taste. Some people have nausea after consuming medicine with urethane content. Urethane is applied to the skin and given orally; it has been reported to cause cancer in small animals.
Of the two, the polyurethane is a little stronger and harder than urethane. Polyurethanes are used in paints for better coverage and gloss. Some benefits of urethane over polyurethane are: low costs, resistance to abrasion, durability in the form of plastics, compression property, good coefficient of friction, stability, shape and size maintenance and resistance to ozone and oxygen.
Polyurethane elastomers have the ability to combine with metals and plastics. These compounds have a high resistance to roughness of the environment. It is much more stable with the effects of solvents. The polyurethane also has good resistance to oxidation.
- The urethane has the functional group R1-O- (CO) NR2-R3 and the polyurethane is the organic group chain of urethanes.
- Polyurethane is harder than urethane; therefore its uses are many.
- It was reported that polyurethanes are not toxic in humans. Urethane may not be suitable for use by many. In small animals, it can cause cancer when administered orally.
- Urethane is used mainly in the preparation of insecticides and in certain medicines. Polyurethanes are used in the manufacture of foams, gel cushions, insoles and solid and hard plastic articles.