By Sean Fenske, Editor-in-Chief

Many medical device development projects start at the logical first building block—the materials. It is critical to explore this area early in design as conflicts between substances can interfere with later steps in a product fabrication plan. Material selection later in the timeline can lead to costly redesigns or create delays in getting a new product to market.

One popular material choice for a variety of medical devices is silicone. While it offers applications across a range of devices and in a variety of clinical areas, its full breadth of benefits is not always completely understood by design engineers considering its use. Therefore, these professionals seek the expertise and knowledge of experienced material partners much more familiar with it.

With this in mind, Kai Opdenwinkel, Vice President & General Manager, Specialty Components, at Freudenberg Medical, provided insights on silicone in the following interview. In this Q&A, he speaks to the many use areas for silicone in medtech applications. He also provides insights into its benefits and how it can be used to improve the overall outcome of a medical device.

Sean Fenske: Why is silicone an ideal material for healthcare and in medical devices? What characteristics make it so?

Kai Opdenwinkel: Silicone offers more design flexibility than virtually any other material. It can be molded into complex geometries with tight tolerances, enabling engineers to create intricate designs that support both function and aesthetics.

Beyond its versatility, silicone is chemically inert and highly stable; it won’t degrade under normal conditions and can withstand repeat sterilization cycles. Many silicones also come with certified biocompatibility, meaning they’re safe for use in contact with the human body. Specialized formulations can even be implanted long-term, making silicone an excellent choice for devices such as port systems, cochlear implants, and gastric bands.

Fenske: Where is silicone most commonly used? What types of medtech applications? Why?

Opdenwinkel: Silicone is used across a wide spectrum of medical technologies due to its unique combination of biocompatibility, flexibility, and chemical stability. It plays a critical role in both implantable and external medical devices.

In implantable applications, silicone is widely used in products such as pacemaker leads, port systems, and long-term vascular access devices, as well as in reconstructive and orthopedic implants—including artificial joints, prosthetic liners, and replacement components for knees, hips, shoulders, and finger joints. Its ability to remain stable within the body and resist biological degradation makes it ideal for long-term use.

Silicone is also essential in various non-implantable devices and delivery systems, such as catheters, infusion pumps, and drug-delivery components. Its flexibility and inert surface properties ensure consistent performance in dynamic environments. In addition, silicone elastomers are frequently used for seals, gaskets, and insulation within medical devices to protect sensitive components or electronics from fluid access or contamination. Overall, silicone’s combination of biocompatibility, versatility, and processability continues to make it one of the most trusted materials in modern medical technology.

Fenske: More and more medical devices are getting smaller in size. How does medical silicone help to facilitate this?

Opdenwinkel: Silicone plays a key role in the ongoing miniaturization of medical devices. Its exceptional moldability allows manufacturers to produce extremely small, precise geometries with consistent wall thicknesses—critical for components such as micro-seals, valves, and thin-walled tubing used in minimally invasive and implantable systems.

Advanced liquid silicone rubber (LSR) and high-consistency rubber (HCR) formulations can be molded using micro-injection and multi-shot techniques, enabling integration of multiple functions into a single, compact component. This reduces assembly steps and the device’s overall footprint while maintaining mechanical integrity and biocompatibility. As medical devices continue to shrink in size, silicone remains a key enabler—supporting innovations in catheter systems, implantable sensors, and wearable drug-delivery technologies.

Fenske: Does silicone “play well with others”? In other words, can silicone be combined with other materials and/or additives to provide unique benefits?

Opdenwinkel: Yes, silicone can be engineered to interact effectively with a range of materials, expanding its functionality in medical device design. It can be co-molded or bonded to various thermoplastics, either through chemical bonding by using modified base materials or by the application of surface prep methods such as plasma or primer treatments to promote strong adhesive bonding. This makes it possible to combine the flexibility and biocompatibility of silicone with the rigidity of thermoplastics in multi-material components. One example is the placement of a silicone grip on the tip of a rigid thermoplastic handle.

In addition, silicone’s surface properties can be tailored to meet specific performance needs. For example, surface treatments and coatings can significantly lower the coefficient of friction, improving lubricity for applications such as catheter systems or seals. These capabilities make silicone an ideal material partner—one that readily integrates with other substrates to achieve enhanced performance, functionality, and patient comfort.

Fenske: In addition to the size of medical devices becoming smaller, they are also being developed to be portable (i.e., wearable) or implantable. Does the use of silicone support these trends?

Opdenwinkel: Absolutely! Silicone’s unique combination of flexibility, durability, and biocompatibility makes it exceptionally well-suited for both wearable and implantable medical devices. Its soft, skin-friendly feel and ability to conform to complex body contours provide superior comfort and long-term wearability—critical for continuous-use devices such as sensors, infusion pumps, and monitoring patches.

For implantable applications, silicone’s chemical inertness and proven biostability ensure compatibility with human tissue and bodily fluids, allowing it to perform reliably over years of use. It can also be formulated with specific hardness, color, or permeability characteristics to meet diverse engineering and physiological requirements.

As the medtech industry moves toward more personalized, connected, and miniaturized devices, silicone continues to be a key enabling material—supporting safe, comfortable, and reliable designs for next-generation wearable and implantable technologies.

Fenske: Another trend with medtech is “smart” or connected devices? What’s silicone’s role with these types of products?

Opdenwinkel: Silicone plays an increasingly important role in the development of smart and connected medical devices. Its electrical insulation properties, flexibility, and chemical stability make it ideal for encapsulating or housing electronic components that must remain protected from moisture, vibration, and environmental stress.

In wearable and implantable smart systems—such as biosensors, drug-delivery devices, or neurostimulation implants—silicone acts as both a protective barrier and a biocompatible interface between electronics and the body. It can be precisely molded to integrate sensors, electrodes, or micro-electronics while maintaining comfort and durability.

Additionally, conductive silicone formulations and over-molding processes are enabling the integration of soft electronics and embedded sensors within flexible structures. As connected health technologies continue to advance, silicone remains a key material platform for achieving reliability, comfort, and performance in intelligent medical devices.

Fenske: Do you have any additional comments you’d like to share based on any of the topics we discussed or something you’d like to tell medical device manufacturers?

Opdenwinkel: Success with silicone is not solely a matter of understanding the material—it also depends on advanced processing expertise. Silicone behaves very differently from thermoplastics, requiring specialized knowledge in areas such as tool design, molding parameters, and curing dynamics. For this reason, medical device manufacturers should partner with processors who have dedicated silicone experience and the technical capability to achieve tight tolerances and consistent quality.

Freudenberg Medical has been processing platinum-cured silicones for medical device and pharmaceutical applications for more than 30 years. Across our operations in the United States, Europe, and Asia, we produce precision-molded components and silicone tubing using only medical, implantable, and pharmaceutical-grade materials. Our long-standing focus on silicone processing ensures customers benefit from proven expertise, validated manufacturing processes, and reliable performance in even the most demanding applications.

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