Radiopaque Additives
A common requirement for minimally invasive surgical (MIS) devices is visibility during x-rays or fluoroscopy. Polymers are inherently transparent to this imaging and require specific additives to achieve visibility. Radiopaque fillers commonly blended with polymers for radiopacity include:
Barium sulfate – off white powder that compounds easily into most thermoplastics and is easily colored.
Bismuth subcarbonate – pale white powder provides excellent x-ray absorption with some color matching limitations.
Bismuth trioxide – yellow powder provides excellent x-ray absorption, limited to low/moderate processing temperature polymers and color matching options.
Bismuth oxychloride – white powder with good temperature stability for processing, yet susceptible to UV degradation.
Tungsten – dark grey powder with superior x-ray absorption with color matching limitations.