Plastic material selection for medical injection molding

injection mold

Introduction to plastic material selection

Plastic material selection is an involved process filled with complexities such as medical device classifications, mechanical properties and cost. However, you can streamline the selection process by eliminating classes of plastics and individual plastics based on your specifications, which can help you pinpoint an appropriate material. Second opinions and new device designs can also provide new and / or cost-effective possibilities.

Note that identifying the type of plastic material should take precedence over identifying a specific brand. You should also consider resins based on their availability and performance capabilities.

There are two major families of plastics: Thermoplastics and thermosets. Thermoplastics are moldable at specific temperatures and cool upon solidification. They are defined by their ability to be heated and reheated. Thermosets, on the other hand, remain in a permanently solid state once cooled, making them ideal for sealed products (e.g., rubber O-rings). Products made with thermosets have high temperature resistance.

Thermoplastics for medical devices

Thermoplastics are optimal for medical devices due to their moldability, compliance with FDA and medical classifications as well as their ability to accommodate complex geometries. Their adaptability is paired with melt flow rates, vibration resistance, ergonomics and temperature resistance.

There are two classes of thermoplastics