What is the difference between polyurethane VS rubber?
Polyurethane and rubber are two commonly used elastic materials in many industrial product manufacturing fields. In particular, many parts in the automotive industry rely on these materials, such as gaskets, tires, belts, and hoses. When it comes to vehicle suspension, polyurethane is often compared to rubber bushings because they have similar mechanical properties.
Both rubber and polyurethane are recognized for their elasticity and flexibility. The largest user of polyurethane reaction injection molded (RIM) parts is the automotive industry. Because polyurethane is typically more durable than rubber, it is used in applications that require continuous pressure or continuous stretching and provide a certain degree of bending and sufficient strength. Body parts such as mudguards, bumpers, and spoilers are made of polyurethane.
Rubber's position in the automotive industry is attributed to a single mechanical property - absorption. Rubber is more effective at absorbing vibration than polyurethane. That's why the material is used to make tires, as well as seals, gaskets, and bushings. Rubber-made bushings are more effective in damping and absorbing road noise, vibration, and hardness than those made of polyurethane. Rubber parts make driving quieter, smoother, and are typically original equipment for manufacturers. In applications where anti-vibration bushings are required, rubber is the preferred material.
On the other hand, polyurethane gives the driver a stronger sense of the road, making the driver feel like an extension of the vehicle itself. Because of the continuous stretching and stress on the parts, rubber also wears out faster.
Nevertheless, rubber is still cheaper than polyurethane, which may be another reason why manufacturers use rubber parts in vehicle suspensions. Polyurethane production is a more complex process. Therefore, the cost of polyurethane raw materials is higher than that of natural or synthetic rubber.
Polyurethane and rubber have some differences and similarities. Using these elastomeric materials has its advantages and disadvantages. Ultimately, this will depend on the mechanical properties required for the application.