Journal of Applied Polymer Science, Vol.114, No.4, 2555-2563, 2009
Development of Porous UHMWPE Morphologies for Fixation of Gel-Based Materials
Novel gel-based materials including hydrogels and bioderived polymers show great potential in orthopedics but require a means of mechanical fixation to a substrate. The development of controlled porous Ultrahigh-molecular-weight polyethylene (UHMWPE) morphologies is targeted to expand the future potential for UHMWPE-based composites with such novel bioderived materials. Porous UHMWPE morphologies were produced by means of a sodium chloride leaching process. Compression-molded samples were prepared by dry mixing of sized NaCl particles and UHMWPE powder. These were then soaked in water to remove the porogen, leaving a porous UHMWPE structure. The mass of removed porogen and resulting void density were found to match well with Monte Carlo simulations. Distribution of NaCl particles was greatly influenced by the ratio of particle sizes between NaCl and UHMWPE. Limited percolation was achievable at NaCl concentrations below 50 wt '%, whereas porogen concentrations above 60 wt % led to interconnected networks. Porous UHMWPE scaffolds were impregnated with gelatin to explore the penetration of a gel-based phase. It was observed that the gelatin was able to permeate the UHMWPE to a great extent, except for unfilled voids due either to entrapped air or insufficient channel diameters to accommodate gelatin flow. These results confirm that porous morphologies can be created in a controlled manner and tailored for chosen applications. (C) 2009 Wiley Periodicals, Inc. J Appl Polym Sci 114: 2555-2563, 2009