High-Speed Fabrication of PTFE Catheters via Dip Coating: Achieving Superior Tensile Properties and Processing Control

Poly(tetrafluoroethylene) (PTFE) is known for its excellent biological, thermal, and chemical stability, making it suitable for biomedical applications such as catheters in cardiovascular therapy. However, conventional processing methods such as extrusion and cold-pressing often require complex operational controls, including utilizing lubricants, precise pressure, and high-temperature thermal treatment. These processes not only demand high energy consumption but also result in manufacturing defects, e.g., stress concentration and undesired micro- or meso-porosity. Here we demonstrate an efficient fabrication process of PTFE catheters based on dip-coating in laboratory with capacity of engineering scale-up to industrial manufacturing, the resulting catheters, with inner diameter ranging from 0.3 to 1.5 mm and thickness of 4–12 mm, exhibit excellent tensile properties that have breaking strain exceeding 700%, outperforming the commonly reported value of PTFE products, and achieve a breaking strength of 45 MPa, overmatching other commercial films produced by coating. We also determined key influencing factors in catheter fabrication, including sintering to improve mechanical properties and surface modification for further adhesion. The work presents an additive manufacturing of medical catheters via high-speed solution coating that is facile in tuning dimensions and mechanical properties; the methodology herein may be extended into the processing of many other polymer thin-wall tubes.