NOVEL BLOOD-COMPATIBLE POLYURETHANES CONTAINING POLY(BUTADIENE) SOFT SEGMENTS AND PHOSPHATIDYLCHOLINE ANALOGS FOR BIOMEDICAL APPLICATIONS

New segmented polyurethanes (SPUs) based on stearyl and phosphatidylch oline analogues were synthesized. The soft segments used in this study were the poly(butadiene) (PBD) glycol, the hard segments of these SPU s were composed of 4,4'-methylenediphenyl diisocyanate (MDI), 2-[bis(2 -hydroxyethyl)methylammonio]ethy stearylphosphate (BESP), and 1,4-buta nediol (BD). The bulk and surface characterization was investigated by differential scanning calorimetry (DSC), X-ray diffraction, attenuate d total reflectance Fourier transform infrared spectroscopy (ATR-FTIR) , and contact angle measurements. The mechanical properties were inves tigated by dynamic viscoelasticity and tensile property experiments. T he blood compatibilities of the new SPUs were evaluated by platelet-ri ch plasma (PRP) contact studies and viewed by scanning electron micros copy(SEM). The results show that this new material has good mechanical strength with an elongation at break of 252%, and the blood compatibi lities of the SPUs have a great difference between the glass contact s ide and air-exposed side for the same cast films. The hot-pressed film s, having same polyimide contact surface, show that the phospholipid S PU is a favorable surface in terms of platelet adhesion and that the m orphology of adhered platelets undergoes a relatively low degree of va riation. The clotting time of the cast films contacting with PRP was m ore than 240 s for the new polymers and 122 and 86 s for polystyrene a nd glass, respectively.