Covestro has released a list of polycarbonate-friendly disinfectants for use in healthcare settings during the COVID-19 pandemic.
The Covestro list narrows an Environmental Protection Agency-generated list of disinfectants approved for COVID-19 cleaning in healthcare settings to ones that are less likely to damage plastics used in medical devices.
Several of the EPA-recommended disinfectants have been tested for compatibility with Covestro polycarbonates and polycarbonate blends commonly used in durable hospital equipment, according to a two-page guide from the Pittsburgh-based company.
Chemical compatibility was assessed by bending molded tensile specimens to a fixed flexural strain of 1.0% (21-25 MPa stress) and then wiping the strained surface with the disinfectant. This accelerated test more closely replicates actual in use exposure compared to other test protocols which use surface saturation over an extended period, the company said.
Ten consecutive wet-to-dry wipe cycles were completed within 9 hours, with a ≥30-minute interval between wipe cycles for drying. After 24 hours of total strain exposure, the specimens were checked for retention of tensile properties per ASTM D638. The dominant failure mode of polycarbonate-based materials exposed to disinfectants is environmental stress cracking. None of the disinfectants changed the surface finish of the specimens, and all observed property changes were associated with the
formation of stress cracks, the company added.
You can find a link to the two-page Covestro document here.
