Polyurethanes are a highly variable family of polymers. Polymers are materials that result from the linking of a chain of simple, repetitive molecules. Polyurethanes can be seen in numerous forms and can be put to numerous uses depending upon how their properties are manipulated. Polyurethane resin, which is a synthetically produced sticky substance, is one of those forms.

Polyurethane resin is an industrial product. It is used in the production of many other products, such as rubbers and medicines. To understand polyurethane resin, it is best to have a basic understanding of how polyurethanes are made.

An isocyanate is a compound composed of nitrogen, carbon, and oxygen. Exposure of this compound to a hydroxyl, a compound that contains hydrogen, will produce a reaction. The association of these two compounds forms a urethane linkage.

A diisocyanate is a compound that contains two isocyanates. These are, therefore, also reactive to hydrogen. Diisocyanates are mostly produced for the role they play in making polyurethane, which is a reaction that involves more than one urethane linkage.

Polyols are basically alcohols that contain more than one hydrogen atom. Producing polyurethane resin generally involves allowing a reaction between a polyol, such as polyether polyol, and a diisocyanate, such as toluene diisocyanate. Heat or catalysts are also necessary to complete the process. When the heat or catalysts are added, the polyurethane resin will generally take a final and irreversible form. This means it may be impossible to reform them even if heat is added again.

Polyurethane resin is considered versatile because it can be used to produce an array of items, from inks to plastics. This is possible because the material can be manipulated to great extremes, which can change properties such as the hardness and elasticity. In many cases, polyurethane resin is produced in a liquid form and can be poured into molds. When used for this purpose, the material is highly impressionable. This means that the slightest detail, such as a small crack, can be seen in the finished product.

Polyurethane resins have many advantages. They are commonly noted for their chemical, oil, and grease resistance. They are typically excellent in resisting abrasion and as such are not easily torn. This can explain why they are often used to produce synthetic rubbers. Additionally, they can be used to create strong adhesives.

There are also some disadvantages to using polyurethane materials. For example, such items can be adversely affected by direct sunlight. They also generally do not hold up well when exposed to organic solvents.