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Rigid Plastics for Medical Device Packaging: PET vs. PETG vs. HIPS

November 4, 2021|BY: Rob Helmke

Custom Thermoformed Healthcare Packaging
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In industries such as medical device packaging, where even the slightest oversight can be problematic for end users, it’s critical that products are designed with the highest possible structural integrity. From small blister packages and plastic lids to medical trays and clamshells, these protective materials must be sterile, FDA-approved, and impact-resistant to ensure end user safety.

Why Package Your Medical Device in a Rigid Plastic?

To ensure patient safety, medical device packages must meet a number of stringent requirements including:

  • Tamper-evident
  • Sterile
  • Product-visibility
  • Easy to open

Rigid plastics — of which there are several subsets — fulfill each of these conditions, allowing for durable, reliable thermoformed solutions. Four of the most popular types of rigid plastics for medical device packaging are:


Thanks to its high-strength barrier and versatility, polyethylene terephthalate (PET) is one of the most popular plastic choices for thermoforming. It can be molded into nearly any shape before being cooled to enhance durability. The resulting resistance to tampering and outside elements makes PET suitable for sensitive applications such as food containers, beverage bottles, and medical device packages.


Commonly used for high-volume, thin-gauge packaging, amorphous polyethylene terephthalate (APET) contains the same polyester makeup as PET plastic but refers to the specific stage at which the material is still amorphous before molding. Manufacturers must treat APET with care, as overheating it or heating it for too long can cause the plastic to become hazy or brittle.


Polyethylene terephthalate glycol-modified (PETG) is created by adding the glycol modifier cyclohexanedimethanol (CHDM) to standard PET. The introduction of CHDM inhibits hazing and crystallization (a risk for both PET and APET, as mentioned above) by adding a secondary diol monomer to the polymer structure and breaking up the linear ethylene glycol chain.

Because it’s much less susceptible to becoming brittle, PETG is suitable for higher temperature processes such as radio frequency (RF) sealing, heat sealing, and other procedures required by blister packs and clamshells. It’s slightly softer surface does, however, make PETG more prone to scratching or weakening from exposure to UV light.


After the polyethylene family of plastics, high impact polystyrene (HIPS) is one of the most popular materials for thermoforming. Similar to APET, HIPS plastics are brittle, amorphous, impact resistant, and clear — though the addition of modifiers allows manufacturers to change its color for desired aesthetics.

Also, HIPS’ excellent hygienic qualities make it suitable for sensitive food packages and sterile medical device trays, while its low weight, recyclability, design versatility, and cost-effective production process make it particularly appealing for consumers.

Want to Learn More?

Plastic Ingenuity is a custom thermoformer with years of experience developing innovative packaging solutions from each of these materials. Our team of automation packaging engineers understands the high stakes involved in medical device packaging and is dedicated to learning every aspect of our customers’ businesses in order to create the ideal packaging solution for their specific needs.

For information on packaging best practices for the medical industry, download our free eBook, “How the Top Pharma Brands are Effectively Automating Their Packaging Systems.”