www.elsevier.com/locate/jmbbm Available online at www.sciencedirect.com Research Paper Mechanic and surface properties of central-venous port catheters after removal: A comparison of polyurethane and silicon rubber materials Ulrike Braun a,n , Edelgard Lorenz a , Christiane Weimann a , Heinz Sturm a , Ilham Karimov b , Johannes Ettl c , Reinhard Meier d , Walter A. Wohlgemuth e , Hermann Berger b , Moritz Wildgruber b,f a BAM Federal Institute for Materials Research and Testing, Unter den Eichen 87, 12200 Berlin, Germany b Department of Diagnostic and Interventional Radiology, Klinikum rechts der Isar, TU, München, Germany c Department of Obstetrics and Gynecology, Klinikum rechts der Isar, TU, München, Germany d Department of Radiology, Universitätsklinikum, Ulm, Germany e Department of Radiology, Universitätsklinikum, Regensburg, Germany f Department of Clinical Radiology, Universitätsklinikum, Münster, Germany article info Article history: Received 20 June 2016 Received in revised form 27 July 2016 Accepted 1 August 2016 Available online 5 August 2016 Keywords: Central venous access port Complication Polyurethane Silicon rubber Structure property relationship Mechanical testing abstract Central venous port devices made of two different polymeric materials, thermoplastic polyurethane (TPU) and silicone rubber (SiR), were compared due their material properties. Both naïve catheters as well as catheters after removal from patients were investigated. In lab experiments the influence of various chemo-therapeutic solutions on material proper- ties was investigated, whereas the samples after removal were compared according to the implanted time in patient. The macroscopic, mechanical performance was assessed with dynamic, specially adapted tests for elasticity. The degradation status of the materials was determined with common tools of polymer characterisation, such as infrared spectro- scopy, molecular weight measurements and various methods of thermal analysis. The surface morphology was analysed using scanning electron microscopy. A correlation between material properties and clinical performance was proposed. The surface morphology and chemical composition of the polyurethane catheter materials can potentially result in increased susceptibility of the catheter to bloodstream infections and thrombotic complications. The higher mechanic failure, especially with increasing implantation time of the silicone catheters is related to the lower mechanical performance compared to the polyurethane material as well as loss of barium sulphate filler particles near the surface of the catheter. This results in preformed microscopic notches, which act as predetermined sites of fracture. & 2016 Elsevier Ltd. All rights reserved. http://dx.doi.org/10.1016/j.jmbbm.2016.08.002 1751-6161/& 2016 Elsevier Ltd. All rights reserved. n Corresponding author. Fax: þ49 30 8104 1627. E-mail address: ulrike.braun@bam.de (U. Braun). journal of the mechanical behavior of biomedical materials 64(2016)281–291