While many people have probably heard of polyurethane, they may not be aware of isocyanates. Isocyanates are used as one of the raw materials when producing polyurethane and are a component in varnishes, paints, and adhesives.
Formation and characteristics
The isocyanate molecule will include nitrogen, carbon, and oxygen as a group of atoms in what is referred to as an alkyl chain or sometimes as an aromatic ring. Isocyanates can be mono, double or more depending on how many aromatic rings they have. The most popular tend to be diisocyanates, which feature two active alkyd groups. Polyurethane is generated when a diisocyanate is combined with another substance, called a polyol, that has active hydroxyl groups.
Working with isocyanates
Isocyanates are versatile, as they occur in powder and liquid form. Certain precautions need to be taken when working with liquid isocyanates, as they can give off vapors that should not be inhaled. Preventative measures need to be implemented when working with these substances to avoid damage to human health and the environment. An article in the Guardian explains more about the dangers of toxic chemical fumes.
There are ways of making isocyanates safer to work with, which include making them less reactive and volatile. The main ways of doing this are by a process of blocking the isocyanates or pre-polymerising them, meaning that larger and easier to handle molecules are generated.
Polyurethane and isocyanates are very useful compounds, especially when it comes to making metal bonding adhesives. Polyurethane is also used in many other types of adhesive where a strong and lasting bond is required. This will be effective on a wide range of materials, depending on the precise composition of the adhesive. If you want to discover more about the specifics of metal bonding adhesives, a useful starting point would be to contact a reputable metal bonding adhesives supplier to obtain advice about the best products to use in particular circumstances.
Isocyanates have wide applications in the industrial world. As a fundamental component of polyurethane, they are incredibly useful and their versatility means a huge range of products, including adhesives, can be manufactured using them. While some precautions need to be adopted when working with these compounds, the end results make modern life easier by providing a range of sought-after solutions.