Thermosets and Thermoplastics

Thermoplastic elastomers, also known as thermoplastic rubbers, or simply TPEs, are some of the best materials for when your product needs to have more flexibility. In this week’s blog post, we will go over the different types of thermoplastics, a brief history, and the benefits compared to other materials.

Different Types of Thermoplastics

According to ISO 18064, commercial TPEs come in six different classes, each with slightly different properties that make it suited for certain tasks and applications.

Styrenic block copolymers, TPS (TPE-s)

TPS are tri-block copolymers containing an elastomeric midblock and a polystyrene endblock. They are non-toxic, odorless and resistant to many different chemicals and conditions. This makes them highly suitable to outdoor conditions.

Thermoplastic polyolefinelastomers, TPO (TPE-o)

TPOs are based on a polyethylene backbone. They offer low-density and high flexibility and are commonly used as additives to PE and PP compounds to make them more flexible.

Thermoplastic Vulcanizates, TPV (TPE-v or TPV)

TPVs are produced by dynamic vulcanization or cross-linking of a rubber during blending and melt-processing with a thermoplastic at elevated temperature. TPVs are inexpensive and can be produced in high-volume, making them a good alternative to cheaper elastomers.

Thermoplastic polyurethanes, TPU (TPU)

TPUs are a linear segmented block copolymer composed of both hard and soft segments. TPUs, like other elastomers, are flexible, but also offer additional sturdiness, high resilience and a good compression set, making the incredibly versatile.

Thermoplastic copolyester, TPC (TPE-E)

TPCs combine the flexibility and strength of thermoset rubber with the processing ease of engineered plastics. They are high performance and high temperature elastomers suitable for extreme conditions.

Thermoplastic polyamides, TPA (TPE-A)

TPAs are light-weight thermoplastic elastomers based on polyester-amide (PEA), polyether-esteramide (PEEA), or polyether-amide (PEBA) block copolymers. They have incredibly low temperature flexibility, making them suited for chemical environments.

Not classified thermoplastic elastomers, TPZ

TPZs are thermoplastic elastomers that do not fall in any of the above categories.

History of Thermoplastics

While the origins of TPEs date back to the 30s with the invention of poly vinyl chloride by DuPont, TPEs became readily available with the advent of thermoplastic polyurethane polymers in the 1950s.

The 1960s saw styrene block copolymer become available, and by the 1970s there were a ride range of TPE materials available commercially.

Benefits of Thermoplastics

TPEs have many benefits compared to other materials such as PTFE or silicone.

• More Eco-Friendly than PTFE
• More Cost Effective than Silicone
• Consistent
• Medical and Food Safe
• Incredibly Versatile compared to other materials

If you need a material that is flexible, versatile, cost effective and eco-friendly, consider using thermoplastic elastomers!

If you need TPE seals, bearings or other industrial solutions, contact us at Advanced EMC Technologies today!

Thermoplastics for medical devices are becoming increasingly common. New materials are often the necessary building blocks for product development and technology breakthroughs in the medical device industry. With novel procedures and treatments emerging rapidly, the equipment and devices required to enhance such advances are frequently limited only by their materials of construction.

A wide variety of thermoplastic resins are used in the medical industry. Most applications have multiple requirements that must be met, which narrows the list of candidate materials considerably. Some of the most common selection criteria include chemical resistance, temperature resistance, impact resistance, elongation or flexibility, strength, stiffness, clarity, dimensional stability, and biocompatibility, among others.

In this week’s blog post, we will discuss some of the most common thermoplastics used in the medical industry.

PTFE

PTFE (Polytetrafluoroethylene), also known by its brand name Teflon, is a fluoropolymer most famous for its non-stick qualities. PTFE is inert to most chemicals and has the lowest coefficient of friction of any thermoplastic. It also has very good UV resistance, hot water resistance and electrical insulation even at high temperatures.

These features make it suitable for a variety of medical applications. It is most commonly used in tubing, keeping devices such as ventilators running smoothly. PTFE coating is also popular for use in vascular medical devices, such as catheters.

PEEK

Like, PTFE, PEEK (Polyetheretherketone) is well suited for a wide variety of medical devices. In particular, PEEK Optima and Zeniva PEEK are suitable for long term implants and have a uniquely similar structure to that of human bone. PEEK is also radiolucent which makes it well suited for dental implants and use in various medical instruments. Not only that, but PEEK is also able to be used continuously to 480°F (250°C) and in hot water or steam without permanent loss in physical properties.

For more hostile environments, PEEK is a high strength alternative to fluoropolymers. Because of this, PEEK is an increasingly popular FDA approved replacement for metal in the medical industry due to its lightweight nature, mechanical strength, radiolucent properties, creep and fatigue resistance, as well as its ease in processing.

UHMW-PE

UHMW-PE (Ultra-High Molecular Weight Polyethylene) is a low-pressure polyethylene resin that has a much higher abrasion resistance and impact strength compared to most plastics. Due to its self-lubricating, non-stick surface, it has a low coefficient of friction that makes it desirable in the medical industry. UHMW-PE’s biocompatibility has made it a popular biomaterial for joint replacements such as hips, knees and shoulders, for decades, as early as the 1960s.

Recently, the resin has been refined in such a way to serve the needs of surgeons doing minimally invasive surgical implants such as cardiovascular surgery. Because of its ability to be shaped into a range of textile constructions, UHMW-PE is suitable for enhancing the design of various implantable cardiovascular devices, including complicated stent grafts and covered stents.

TORLON-PAI

TORLON PAI (Polyamideimide) is one of the highest performing thermoplastics built from the TORLON resin. Its compressive strength is double that of PEEK when unfilled, and about 30% higher than ULTEM PEI. As a medical grade thermoplastic, Torlon offers high modulus, radiolucency, sterilization-compatibility and high wear resistance, making it ideal for components inside high performance and peristaltic pumps. Torlon’s extremely low coefficient of linear thermal expansion and high creep resistance deliver excellent dimensional stability over its entire service range.

In Conclusion

While we only went over a mere handful of thermoplastics, there are many more that are used in the medical device industry. Whether you need tubing for a pump, replacement for a bone, or more, there is a high-quality thermoplastic perfect for the task.

To learn more about polymers and their use in medical devices, check out this blog post HERE.

Need FDA approved seals for your medical device? Contact us today!