Let’s cut to the chase: yes.
In fact, silicone may even be ideal. Blasephemy, right?
Not really. Because, like carbon-based polymers, silicones, which have a backbone of silicon, offer temperature resistance, flexibility, clarity, malleability and water resistance. And also just like plastics, they can be formed, shaped, then softened or hardened into practically anything — but especially plastic injection molded medical devices.
Plastic injection molding is a process that seems tailor-made to the production of high-precision complex components for healthcare applications. This is especially true when part-to-part integrity is mandatory over high volume production runs. As with other medical-grade polymers, such as polycarbonates and acrylics, silicone can be sourced for the highest purity. Biocompatible to accepted standards such as ISO 10993 and USP Class VI, silicone is also compliant with European Pharmacoepia 3.2.9. And, also like its plastic cousins, silicone withstands common sterilization methods such as steam, radiation or EtO (Ethylene oxide) very well indeed.
In many applications, silicone is bonded seamlessly to plastic polymers using two-shot or multi-component injection molding. Combining different materials makes possible the creation of the incredibly complex, yet extremely durable single piece plastic medical devices, featuring undercuts and thin walls for example, that our high-tech medical industries demand.
Single-component plastic medical devices are inherently more robust than an assembly of individual parts, which, if any one piece can fail, the entire assembly fails. What’s more, single-component plastic medical devices can be significantly lighter weight and also potentially eliminate the risks and costs associated with secondary assembly in a separate plastic injection molding process.
However, these advantages can only be fully exploited if there is close collaboration between the plastic medical device maker’s engineering team and their counterparts at the silicone component manufacturer. As in most things in life, teamwork is vital.
That said, the heart-and-soul of any successful plastic injection molded component is the tool — the mold itself. And that may be the bigges drawback to plastic injection molding for medical devices: developing a tool-grade steel mold, associated hot- or cold-runner blocks, and related process automation equipment can be expensive and time-consuming.
But the marriage of silicone and plastic polymers is too important to allow these considerations to be paramount. Plastic medical devices demand the very best tools/molds because they are the vert best at what they do.