SURFACE MODIFICATION OF BIOMATERIAL FABRIC USING SUPERCRITICAL N2 JET

Textile biomaterials have been largely used over the last decades as vascular grafts, hernia meshes and heart valve leaflet [1-2]. Once implanted in vivo, the natural porosity of textile materials tends to induce exaggerated tissue ingrowth, which may prevent the implants from remaining flexible [3]. One hypothesized way to limit the foreign body reaction process is to increase the material surface roughness [4]. Supercritical N2 jet particle projection is a novel technique to provide enough velocity to micro particles to induce plastic deformation on the textile impacted surface. The aim of this study is to investigate the influence of micro particles laden supercritical N2 jet projection parameters like jet static pressure, standoff distance and particle size on the roughness of PET fabric surfaces. Results bring out that particles projected by the jet N2 SC generate craters on the surface of monofilament as well as multifilament fabric, allowing topographical modifications at the yarn scale. We found that larger particles induce larger crater diameters. Moreover, increasing the static jet pressure from 300 to 1000 bars further allows increase in the crater diameter. For a pressure of 500 bar, the standoff distance must be greater than 300 mm in order to obtain significant roughness values without breaking the PET monofilament fabrics. Thus, this treatment increased the roughness of the monofilament fabric from 0.78 μm to 1.22 μm. The results obtained in this work show that it is possible to create a roughness on a PET fabric using the N2 jet technology.