Engineering Grade vs. Medical Grade Plastics: Which to Choose?

Not all injection molded plastic parts are the same. Depending on the demands of your business, industry, and end-user, you may need to create parts and devices a cut above standard plastics. Today we’re looking at two common grades—types of plastics and procedures to meet exacting standards—and comparing them. Engineering grade vs. medical grade plastics—which is the right choice for your next project?

Why Would Companies Need Engineering or Medical Grade Plastics?

Much like “military grade” means a rugged and hardened design, both engineering grade and medical grade plastics are used outside of the engineering and medical fields and markets. The ethos behind medical and engineering grade manufacturing takes these even further, typically including additional testing, quality assurance, and other benchmarks. Any plastic part or product can take advantage of these categories of plastics and the additional manufacturing measures surrounding them.

Engineering Grade vs. Medical Grade Plastics

Engineering Grade Plastics

Engineering grade polymers are all about reliance, both in a structural sense and also about reactivity (or the lack thereof) with the environment. Common types of engineering grade plastics include polyamides, polycarbonate, and both polybutylene and polyethylene terephthalates.

• Strength: These plastics are often focused on strength similar to metals, allowing them to not only be load-bearing but also operate on industrial scales and for large engineering projects.
• Stability: These plastics are very chemically stable and tend to be chemically inert when it comes to exposure to common engineering products such as metals, concrete, and water.
• Resistance: Engineering grade plastics generally boast high heat, electrical, and chemical resistance to operate in difficult environments and in contact with corrosive elements.

Learn more in our blog, The Benefits of Engineering-Grade Resins in Plastic Injection Molding.

Medical Grade Plastics

Medical grade polymers are all about safety, providing sterile, one-use or cleanable plastic parts that have increased manufacturing standards. Polyetheretherketone (PEEK), Polyethylene, and Polypropylene are common choices for medical-grade plastic parts.

• Sterility: Polymers and finishes that provide a hostile environment for bacteria, viruses, and other pathogens and vectors.This can be further enhanced with antimicrobial and antiviral additives.
• Cleanability: For reusable parts and devices, having products and parts that are easy to clean and can be sterilized in a medical autoclave or via radiation, meaning high heat and radiation resistance.
• Traceability: A requirement in the medical sector, the ability to trace specific parts back in the supply chain for devices whose failure or defect would be likely to have serious health consequences is key.

Learn more in our blog, The Difference Between Normal and Medical Plastic Injection Molded Parts.

What Plastics Should You Use for Your Products?

While the plastic and manufacturer you choose is up to you, it’s important to keep in mind who your end users are and what requirements you want or need to meet for them. For example, medical devices often need to meet certain ISO (International Organization for Standardization) standards, such as ISO 13485, 14971, and 10993. It’s also important to note that plastics and processes can combine some of the best features for both, such as for life sciences and pharmaceuticals, where both resilience and sterility may be important.

Selecting the right grade and specific type of plastic for your manufacturing is key, but you don’t have to do it alone. Working with the right injection molding manufacturer means getting not only their advice on the right polymer to meet your needs, but also the right quality control and logistics to meet your needs. Midstate Mold are the experts for locally produced parts and high-quality molds prototyped and built to the highest standards. Contact us today to learn more.