Nithin Raikar, Senior Business Manager at SABIC Specialties for LNP Resins and Compounds, discusses the effects that LNP ELCRES CRX PC Copolymers have had in the medical sector.
How has the increased use of disinfectants in healthcare settings brought about a change in the way plastics are used?
SABIC
SABIC versus COVID
Nithin Raikar
Device manufacturers and material suppliers have worked diligently to elevate their understanding of the compatibility of new chemical agents with plastic materials. The COVID-19 pandemic has accelerated the focus on the types of materials used to address infection control challenges. Specifically, device manufacturers are considering newer material solutions with improved chemical resistance to withstand the cumulative effects of cleaning, aggressive disinfectants and the increased frequency in cleaning protocols.
How do SABIC products help maintain the structural integrity of surfaces?
SABIC understands the need to develop materials with improved chemical resistance to help extend the useful life of critical plastic medical products. In terms of traditional polymer chemistry, repeated exposure to aggressive chemicals over time may result in either physical degradation (environmental stress cracking, crazing, swelling and discolouration) or chemical attack (negative reaction of chemical with polymer).
SABIC has innovated to help hospitals mitigate this risk by developing a new family of LNP ELCRES CRX polycarbonate copolymers featuring improved chemical resistance over existing materials. Compared to traditional PC, ABS, and polyester and co-polyester resins and blends, which are potentially incompatible with highly aggressive disinfectants, the new LNP ELCRES CRX copolymers can help prevent stress cracking and mitigate crack propagation. This means that hospitals can continue to use the most aggressive and effective forms of disinfectant without compromising device functionality.
How rigorous were the tests that prove the technology works?
SABIC follows an established environmental stress cracking (ESC) testing procedure (ASTM D543) to screen chemicals and environmental conditions that mimic a part’s typical exposure. We conducted this study to assess compatibility between incumbent materials and twelve leading surface disinfectants widely used to clean devices. This includes many of the disinfectants published on the United States Environmental Protection Agency list that meet their criteria for combatting SARS-CoV-2, the novel coronavirus that causes COVID-19.
To test compatibility with various chemicals, SABIC used a quantitative ESC test that evaluates retention of tensile properties from three to seven days at one per cent strain and at room temperature. With no established industry standard, this exposure range was selected to push the material to its test limits. The test bars are kept saturated with the chemical agent, i.e. they’re wrapped in disinfectant wipes. This test method is one of the most stringent protocols and serves as a highly accelerated version of normal exposure to disinfectant wipes in a healthcare setting.*
How complex is the process of getting these polymers/copolymers to market in Europe?
Applications in the healthcare industry and medical devices have unique and stringent requirements for thermoplastic materials. The proper selection of plastics for medical devices and equipment housings will continue to be a focus to provide better patient safety and reduce operating costs.
It is important for OEMs to involve material suppliers early on in the design process to identify the appropriate materials to support both mechanical requirements (such as flow, impact, creep resistance) and also the growing requirement of chemical resistance performance to withstand harsh disinfectants. As designers explore benefits to utilise new plastic technologies during product development, SABIC offers support beyond material selection in terms of part design and moulding processing. A proactive and collaborative material selection approach supports the ability to bring new materials to market that can meet product performance and address applicable regulatory requirements for medical devices.
*Compatibility criteria may vary since there is currently no agreed-upon industry standard. SABIC defines compatibility as ≥90% retention of tensile stress at yield and 80-139% retention of tensile elongation at break.
This article features in the March/April edition of EPPM Magazine