A series of radiopaque iodinated polyurethanes (I-PUs) used for embolic agents were synthesized via coupling reaction between poly(butylene succinate) PBS and iodinated bisphenol-A (IBPA) with varying compositions using isophorone diisocyanate (IPDI).The IBPA with four iodine atoms per molecule was applied as a chain extender and X-ray contrast agent.The chemical structure and composition of I-PUs were characterized by FTIR and 1H-NMR.The effects of IBPA on crystallization and thermal properties of I-PUs were systematically studied by means of differential scanning calorimetry (DSC)

thermogravimetry analysis (TGA) and wide-angle X-ray diffraction (WAXD).The results showed that the crystallization behavior and thermal stability were restrained with the introduction of IBPA

which was also confirmed by WAXD.However

in the X-radiography analysis

all the synthesized I-PUs and their microspheres exhibited high radiopacity compared with an aluminum wedge of equivalent thickness.As expected

the X-ray visibility was increased with the iodine content increased.Basic cytotoxicity test was conducted by the method of thiazolyl blue tetrazolium bromide (MTT) colorimetric assay and fluorescent live/dead staining.Cells proliferating well on the polymer-coated coverslips demonstrated that all the synthesized I-PUs were noncytotoxic biomaterials.This study presents a facile synthetic route of radiopaque polyurethanes with high iodine contents

which are expected to possess significantly advantage over the traditional polymer counterparts used for embolic agents and other related biomedical applications.