Many medical breathing masks, such as those used in anesthesiology, Continuous Positive Airway Pressure (CPAP) machines and ventilators are transparent for patient assessment and to reduce the sensation of claustrophobia. In addition to clarity, is important that the mask is comfortable and also provides a proper seal of airflow.
Masks are made in a variety of sizes, configurations and materials depending on the applications. The crown of the mask is often made from a transparent polymer, such as SMMA, polycarbonate (PC) or transparent polyamide resin (including Rilsan Clear G170 MED), while the cushion is often comprised of soft silicone elastomers. Clips, valves and other molded components may be made from more rigid components, including PVC
Radel® polyphenylsulfone (PPSU) has been chosen for use in a high-pressure blower components within CPAP machines due to its inherent strength, toughness, and high stress crack resistance. For these applications, PPSU replaces materials such as modified polyphenylene ethers (PPE), offering improved stress crack performance.