Medical product designers know that urethanes can be used where biocompatibility and flexibility are the key features. Electronics and packaging engineers are familiar with urethanes as conformal coatings or potting compounds where water blocking properties are important. Mechanical engineers may select the urethanes as tough, abrasion-resistant materials used for skateboard wheels, processing rollers, and adhesives.
Like the fable of the blind men and the elephant, it is common for specialists in one industry to only see the properties of Urethanes that they are familiar with and overlook others. At Bay Materials we work with clients in a broad range of industries and have specified urethanes for a wide variety of applications. This has given us many opportunities to think about the “whole elephant” with materials we are evaluating or recommending.
While many engineers are aware of low durometer urethanes used for products like catheter tips, many do not realize that transparent urethanes are commercially available with tensile modulus up to about 300,000 psi and even over 2 million with reinforcement and fillers. Bay Materials selected one of these clear, tough materials and modified it further to produce the Zendura line of orthodontic appliance materials used in dental aligners today. This took advantage of the desirable properties of biocompatibility, toughness and clarity of urethane. We have also specified urethane adhesives and coatings for use in the protection of sensing devices, taking advantage of their good adhesive and conformal properties and its strength as a water barrier.
When considering materials applications, it is important to consider all the properties of the material, or consult with someone more familiar with the subject. Don’t cross urethanes off of your list of candidates too quickly. Urethanes exist with an amazing range of properties, which can act as everything from a high-durability top-coat to a soft gasket.
