RADIOPAQUE POLYMERS BASED ON ACRYLATED PHOSPHONATE ESTERS DERIVED FROM POLYOLS

A number of miscible metal salt–polymer systems of acrylated phosphonates derived from various polyols such as glycerol, D‐mannitol, D‐sorbitol, pentaerythritol, and dipentaerythritol are described. The salt–monomer systems could be polymerized radically to form homogeneous transparent glassy polymers. Incorporation of heavy metal salts in polymers imparts radiopacity on otherwise radiolucent materials rendering them useful for X‐ray imaging. The polymer–salt systems have been characterized with the aid of infrared spectroscopy and thermal and radiographic analyses. In these salt–polymer systems, salts are bonded to the polymers predominantly through the phosphoryl's oxygen. The results indicate that about 11 wt % of uranyl nitrate hexahydrate and 12.5 wt % of bismuth bromide impart a radiopacity equivalent to that of aluminum. The glass transition temperatures (Tg) of the salt‐containing polymers are substantially higher than the salt‐free polymers. The Tg values seem to depend on the chemical nature of the polymers, concentration of metal salts, and the extent of crosslinking induced through chelation. The analysis indicated complete solubility in the polymer matrices. No melting point endotherms of free salt crystals were detected. Some preliminary adhesion measurements revealed that acrylated phosphonates are excellent adhesion promoters for hard tissues. Copyright © 1990 John Wiley & Sons, Inc.