New York, N.Y. – This case study, from Solvay Specialty Polymers – a leading global supplier of high-performance thermoplastics offered for use in a range of markets including implantable and non-implantable medical devices – highlights the use of its high-performance polymers in the healthcare field. Surgical retractors made of Ixef polyarylamide (PARA) and AvaSpire polyaryletherketone (PAEK) show strong commercial promise and are the latest examples from Solvay which showcase the advantages of high-performance polymers over metals in medical devices.
An active participant in the metal replacement market for over 25 years, Solvay undertook an innovative commercial approach by applying its knowledge and expertise to develop case studies that help customers see the cost and performance advantages of high-performance polymers in medical devices. The current case study focuses on both single-use and reusable retractor applications that use Ixef PARA and AvaSpire PAEK resins to replace traditional metal instruments.
“Specifying plastics for medical devices can be a major challenge for those who have been used to working with and designing with metals,” said Dane Waund, global market manager for healthcare for Solvay Specialty Polymers. “To help customers make this transition, we conducted an in-depth study on end-use performance, biological safety, and economics, and developed a practical seven-step metal replacement plan.”
Waund noted that high-performance polymers offer the same level of strength and rigidity as some metals at ambient temperature along with added advantages. High-performance polymers deliver cost benefits, enhanced aesthetics, and ergonomic improvements including a range of grip options. They can also be colored, thus enabling the production of devices in a variety of sizes that can be easily and quickly identified in the operating room.
The Hohmann retractor, a popular device used in surgical procedures, was selected for the metal replacement case study because of the challenging requirements including high mechanical loads. In single-use applications, Ixef PARA was used due to its strength and stiffness, excellent surface finish, and compatibility with gamma radiation sterilization. Ixef PARA’s strength and rigidity surpasses that of known competitive thermoplastics, including carbon fiber-reinforced polyetheretherketone (PEEK). This enables instrument designs which offer comparable performance to that of their stainless steel counterparts. The material is injection molded, thus eliminating machining and reducing cost over stainless steel.
For reusable devices, AvaSpire PAEK delivers a range of advantages including a high stiffness-to-weight ratio, hydrolytic stability at elevated temperatures, excellent chemical resistance, as well as excellent aesthetics and colorability.
Stiffness, strength, and compatibility with disinfectants and steam sterilization are critical requirements for reusable retractors, making AvaSpire PAEK ideal for these applications. The material is also easy to process, allowing designs incorporating long, thin geometries to be produced via injection molding.