January 24, 2019 | Brianna Schaeffer

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Is Aliphatic TPU Foam All it's Cracked Up To Be?


Polyurethane raw materials themselves have long seen use as dressings in the medical industry, but aliphatic thermoplastic polyurethane (aliphatic TPU) foams are gaining popularity as options for wound care management. A basic breakdown of the term can help healthcare industry professionals better understand what they're looking at when they deal with aliphatic TPUs:

  • Thermoplastic polyurethane (TPU) on its own is an elastomer. It is fully thermoplastic; so, like other thermoplastic elastomers, TPU is elastic and meltable. It is a linear segmented block copolymer that's composed of both hard and soft segments. 
  • The hard segment of the TPU can be either aromatic or aliphatic. Aliphatic TPUs are light stable and provide users with a high level of optical clarity. Anytime this clarity is valued, or a user needs exceptional adhesion or surface protection, an aliphatic TPU is likely to be a good choice. 

These aliphatic TPUs see increased use as a foam in wound care applications. Because of the chemical properties of the TPU itself, this foam possesses incredible absorption rates and fluid retention capabilities. Wound care solutions that are made out of these polyurethanes also exhibit a balanced moisture vapor transmission rate. This is key to providing adequate protection against contaminants while maintaining moisture breathability to allow tissue to heal.



General Properties

Aliphatic TPU foams are smooth, conformable, and non-yellowing. This means that spotting problems with a wound can happen more quickly; if foam yellowed naturally, it would be difficult for healthcare providers to discern whether discoloration was coming from an infection or was naturally occurring to the foam over time. TPU foams are also especially beneficial to wounds that require a buffering effect-- whether it be for the comfort of the patient, for medical purposes, or both. 

These properties allow aliphatic TPU foams essentially to act as a second skin during the healing process. They keep the wound protected, clean, and buffered while remaining easy to apply and remove. The level of conformity offered by foam means that less time is spent trying to cover or fill in especially deep or oddly-shaped wounds; when applied correctly, aliphatic TPU foams function almost as much as a part of a patient's body as they do a dressing. This makes for a more seamless (and painless) wound care routine for patients and doctors alike. 



Despite the sophisticated manufacturing processes that are often involved in creating polyurethanes, aliphatic TPU foams continue to see increasing popularity in the medical sector. This is because these TPUs can be utilized in situations where other materials simply will not work. Polyurethanes are known for being incredibly versatile within medical applications. They are biocompatible and hemocompatible while maintaining an exceptional level of durability. 

Time has shown that as the population grows, the medical industry can expect to see an increase in demand for wound dressings that can stand up to non-healing ulcers and skin breakdown (decubitus). Aliphatic TPU foams are well suited to these purposes. These materials provide an exceptional ability to absorb exudate from wounds and can even be utilized to clot blood in the cases of more severe injuries. 

Polyurethanes are most tolerant of ETO and irradiation sterilization methods. They can be removed from skin incredibly gently, allowing patients to get through dressing changes more comfortably. This also makes healthcare professionals' jobs easier-- a happy patient is an easy patient. TPUs can also be manufactured and manipulated to suit needs that range throughout various levels of adhesive strength.


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The benefits of aliphatic TPU foams in wound care applications are clear. Whether a wound is large or small, complex or simple, a foam dressing that is efficient at absorbing exudate is an excellent care choice. The fact that these foams are so well-suited to biocompatibility, maintaining adequate moisture levels, and more, further cements the idea that they are all they're cracked up to be.  


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