Customizing self-lubricating silicone elastomers to move medical device fabrication forward
Due to its biocompatibility, processability and wide range of physical properties, liquid silicone rubber (LSR) is ideal for injection-molded valves, O-rings and other precision medical device parts. At the same time, the inherent tackiness, blocking tendency (sticking to itself) and the high coefficient of friction (COF) of silicone elastomers pose challenges to device design and fabrication. These properties may cause self-healing of one surface against another or prevent the desirable sliding and gliding action between surfaces in many devices. The traditional solution to these challenges requires medical device manufacturers to apply a silicone lubricant onto the molded part as a separate manufacturing step.
During regular discussions with a customer over how to boost productivity, a medical device manufacturer asked the question, “Can you make a silicone elastomer that lubricates itself?”, Their thinking was that if a silicone elastomer can be customized with the silicone lubricant already in the material, then the manufacturing step of applying the lubricant on the surface could be eliminated.
To answer that question, NuSil® experts drew on their years of experience and turned to their “toolbox” of resources that facilitated the customization of a successful self-lubricating silicone elastomer for this customer’s specific needs.
According to Dr. Jim Lambert, NuSil® Director of Technology and Innovation for Biomaterials, “When we’re collaborating with a customer to identify a solution, we explore a lot of options in our formulation database. Our goal is to characterize the requirements for an elastomer that contains a silicone oil and demonstrates the required modulus, strength and CoF”.