New Latex-Free Options for Tourniquets and Similar Devices

Teknor Apex Co.'s Medalist family of thermoplastic elastomers now includes new compounds for cast-film applications.

Daphne Allen

The latest compounds in the Medalist TPE family can be used
for tourniquets and other cast-film products.

Cast-film products such as tourniquets and straps, therapy bands and sheeting, and dental dams now have new latex-free options. Teknor Apex Co. has expanded its latex-free Medalist thermoplastic elastomer family to include new compounds for such film applications. The medical-grade TPEs offer the same elasticity, durability, and "feel" of latex without concerns regarding allergic reactions, odor, or residual curing agent, according to Teknor Apex, which will be highlighting the materials at MD&M West 2017 in Booth #2438.

The Medalist line itself was introduced in 2009, and it includes medical-grade TPEs including but not limited to stryrenic block copolymer (SBC) compounds, thermoplastic vulcanizates (TPVs), and specialty blends, said Ross van Royen, senior market manager for regulated products for Teknor Apex. The new materials for films were launched in November 2016.

Van Royen told Qmed that there is "a trend away from thermoset materials towards thermoplastics, for cost reduction. Latex is one of many thermoset materials used in the medical industry." The Medalist TPEs offer lower per-pound cost, elimination of the curing step, and the inherently greater processing efficiency of thermoplastics, according to the company. Scrap reduction is possible, as is lower part weight and conversion cost and easier processing, adds van Royen. Savings can also be seen when Medalist TPEs are compared with other thermoset rubbers such as nitrile or neoprene.

In addition, using Medalist TPEs eliminate the protein allergy issue associated with natural rubber latex, van Royen said. Also, "NR latex has higher extractables/leachables from cure system," he added.

Finally, Medalist compounds feature low odor and lower specific gravity when compared with natural rubber latex.

Teknor Apex formulated the new materials to duplicate the performance of latex rubber, and their nature may also offer new design possibilities. "Medalist TPEs could lead to previously unexplored design possibilities," van Royen said. "Unlike thermoset rubber latex, Medalist TPEs can be molded or extruded into films, and they are bondable to polyolefins and TPE materials. Medalist TPE film grades can be clear, can perform well at extreme low temperatures, can be heat sealed, etc." They are also recyclable, he added.

And "designers should know that they are not limited to the grades in our standard portfolio; custom formulations can be developed," he said.

As is the case with any material change in a medical device, the device would have to be re-qualified, van Royen said. "New conventional thermoplastic processing equipment would be needed, but it has a lower manufacturing footprint," he said.

The process change itself could offer benefits. "Rubber extrusion is complicated, in terms of both equipment and production methods," van Royen explained in a news statement. "Because it is a lot easier and less expensive to set up a TPE extrusion process than one for rubber, companies may find it attractive to bring the manufacture of film products in-house rather than outsourcing it."  

The entire Medalist line offers the following characteristics:

The new Medalist compounds duplicate the elastic behavior of latex (see stress-strain graph) while providing similar resilience and durability (see table of properties). They also exhibit similar haptics (tactile qualities) and draping behavior--important in clinical settings.

Daphne Allen is executive editor of Pharmaceutical and Medical Packaging News and a contributor to Qmed. Reach her at [email protected].