Novel Thermal Rheological Fluid with Arterial Embolic Function, Using Side Chain Crystalline Block Copolymer

We polymerized a hydrophilic side chain crystalline block copolymer (SCCBC) by nitroxide-mediated living radical polymerization. The polymerized SCCBC changed the surface of polyethylene (PE) to hydrophilic and enabled dispersing PE particles in a polar solution. In addition, the PE particle suspension behaved as thermal rheological fluid (TR fluid). By using the SCCBC, PE particle and contrast medium (as a solution), we prepared a new functional TR fluid as an artery embolization agent. This new functional TR fluid showed a transition temperature near the body temperature and changed to solid. Furthermore, this TR fluid could be injected into the renal artery of a rabbit under X-ray fluoroscopy and sustained embolization for 28 days. This result indicates that the TR fluid could be used as embolic or hemostatic agent.