| Radiopaque Additives |
- Barium Sulfate (BaSo4): Barium sulfate is an economonical, biocompatibile, white crystalline powder that is easily compounded and colored. It provides excellent stability under heat, UV radiation, and chemical attack. With a specific gravity of 4.5, it offers fair radiopacity in 20-40% loadings by weight.
- Bismuth Subcarbonate (Bi2O2(CO3)): Bismuth subcarbonate is a off-white powder that occurs naturally. With a density of 6.86, it provides good radiopacity, but is hard to color, and will discolor under UV light.
- Bismuth Trioxide: Bismuth trioxide is a natural yellow powder with excellent radiopacity. It has a specific gravity of 8.9, but its color and temperature stability limits its application to select polymers.
- Bismuth Oxychloride (BiOCl): A naturally off-white powder with a specific gravity of 9.3. It has excellent radiopacity, but is susceptible to UV discoloration.
- Tungsten (W) metal: A dark gray metal, tungsten has a specific gravity of 19.3 making it an excellent radiopaque material. It is commonly used in market band and catheter tip applications, but is generally not used in long-term implantable devices.
- Tungsten Carbide (WC). A gray powder, Tungsten Carbide has a density of 15.8. It has superior radiopacity, but has limited color applications and its hardness also can make it difficult to process.
- Others: Other radiopacifiers include platinum, palladium, and gold metal.
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| Specialty Additives |
- Lubricants - used to modify the surface or internal friction of the polymer.
- Process Aids - waxes and other technologies to aid in processing such as extrusion, injection molding, or dip coating.
- Heat Stabilizers - used to improve thermal stability to prevent degradation during both processing and the final application.
- UV Stabilizers - used to shield a polymer from UV attack and to improve the long-term stability.
- Antioxidants - involve using a variety of technologies to increase shelf life and long term stability.
- Fillers: Mineral, Talc, Calcium carbonate
- Reinforcements
- Fiber
- Beads
- Nanocomposite
- Flame Retardants
- Antimicrobials
- Impact Modifiers - used in co-polymers to improve ductility and impact properties
- Others: anti-static fillers, shielding agents, conductive, and magnetics.
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