Medical tubing manufacturers have a variety of compound options, ranging from flexible plastics to TPEs to natural and synthetic rubbers. The most widely used material by far is PVC, which for decades has been employed in numerous types of tubing. More recently, TPEs have emerged as promising candidates and are in successful use by tubing manufacturers. Teknor Apex offers TPE compounds alongside its broad range of PVC products for tubing.
Flexible PVC compounds cost less than any current or proposed alternative material—a critical advantage for high-volume items like IV sets. They are available in a very broad range of durometers, from very soft to semi-rigid, and can be bonded to virtually all of the plastics typically used for molded connectors. The crystal clarity of PVC is obviously of great practical value in clinical use.
PVC can be sterilized with all standard methods. Special gamma-stable formulations exhibit minimal color changes following gamma irradiation. While general-purpose PVC compounds provide strength and chemical resistance for a wide range of applications, compounds are available for tubing requiring high tensile strength, abrasion resistance, or kink-resistance at low durometers.
Among the alternatives to PVC for tubing, there is now available a range of TPE compounds that mirror the clarity, haptics, physical properties, kink resistance, and clamp resistance of PVC while exhibiting enhanced gamma stability and flexibility. Unlike silicone rubber, they provide the processing ease and design freedom of thermoplastics, while avoiding concerns about extractables and curing agents. Compared with silicones and TPUs, the new TPEs offer an economic advantage.
Teknor Apex has developed TPE tubing formulations for use in a variety of medical assemblies. TPE tubing sets can be assembled using commercially available UV curable adhesives. In addition, a specialty grade makes solvent bonding possible. Sterile TPE tubing welds are readily achievable using a Terumo welder or other comparable systems.
