Various-sized stearyl poly(ethylene oxide) coupling-polymer blending poly(ether urethane) material for surface study and biomedical applications

Three types of stearyl poly(ethylene oxide) (SPEO) with different values of M_n, 2300, 6000 and 12000, were synthesized by an anion polymerization from the ethylene oxide (EO) monomer with the initiator, sodium salt of stearyl alcohol. Consequently the amphiphilic coupling polymers of 4,4′-diphenylmethane diisocyanate (MDI)-SPEO (SPEO-MDI-SPEO, MSPEO 2300, 6000 and 12000) were synthesized and the blended poly-(ether urethane) samples of PEL-MSPEOs (PEL-MSPEO 2300, 6000 and 12000) were prepared via a solution process. The surface analysis with ATR-FTIR, angle-dependent XPS and two methods of contact angle measurements (sessile drop and captive bubble) were performed. The results of the analysis indicate that the dominant factor for the monoblock behavior of long-chained MSPEO 12000 is the PEO chain. However, for short-chained MSPEO the factor is C₁₈ and the dominant effect is not so overwhelming compared to that of PEO for long-chained MSPEO. Simultaneously, the size of the molecule will also dramatically affect MSPEOs' kinetic behavior including the monoblock mobility and the reconstructing of the surface conformation, i.e. the smaller the size, the faster the movement. The static test of clotting time, PRT, was also performed. The results indicated that the modified surface could resist the clotting much more effectively than that of the untreated surface. © Wiley-VCH Verlag GmbH, 2000.