Polyurethane
What is polyurethane?
Polyurethane (PU) is a resilient, flexible and durable manufactured material. There are various types of polyurethanes, which look and feel very different from each other. They are used in an extensive range of products. Polyurethane-containing products surround us in every aspect of our everyday lives. While most people are not familiar with polyurethanes because they are generally hidden behind covers or surfaces, it would be hard to imagine life without them.
Properties of polyurethanes
Polyurethanes are affordable and safe materials, and they are also sustainable. They preserve the Earth’s natural resources by reducing the need for energy.
Polyurethanes make our lives more comfortable, from the relaxation provided by foams in furniture and bedding to the insulation regulating the temperature inside buildings. In cars, their cushioning properties help protect drivers and passengers in case of collision.
The material’s enormous adaptability, availability, affordability and recyclability make it a practical choice for many manufacturers.
How polyurethanes are used
Polyurethanes are found in a wide range of applications, including:
● Building insulation
● Cooling devices, e.g., refrigerators and freezers
● Furniture and bedding, e.g., mattresses
● Footwear
● Automotive applications, e.g., car seats, interior parts
● Coatings and adhesives
Polyurethane innovations
Polyurethane is helping footwear manufacturers to achieve their sustainability goals. Typically, most athletic shoes are made from a dozen or more materials, leading to a complicated supply chain and a larger carbon footprint. Brands including Balenciaga and Adidas are now creating vegan-friendly shoes made entirely from polyurethane to reduce the length of the supply chain.
Water storage mats made from polyurethane can help improve a city’s urban climate as part of a roof greening system. Roofs make up around 30-50% of a city’s surface area. When roof greening systems are installed, they act like settlement biotopes, improving rainwater management and air temperature in the immediate vicinity. They also help to save energy for heating and air conditioning systems. Compared with alternative materials, polyurethane foam offers a higher water absorption and draining capacity while remaining lightweight and long-lasting.
Recycling and reuse of polyurethane
Polyurethane can be recycled in one of two ways: either mechanically, in which it’s reused in its polymer form, or chemically, in which it’s broken back down into its chemical components. Common uses for recycled polyurethane include carpet padding, boards and mouldings that can be used in soundproofing and flooring, and even as raw material for new polyurethanes.
Further reading
Polyurethane helps shoe manufacturers reach their sustainability goals
Innovative roof greening for better ecology, climate and economy
Closing the loop: polyurethane recycling for a sustainable future