In vitro biocompatibility of PTMO-based polyurethanes and those containing PDMS blocks

In this work, a series of different polyurethanes based on poly(tetramethylene oxide) (PTMO, MW approximately 2000) and chain extended with butenediol were synthesized by a two-step solution polymerization. Three of them contained silanol terminated polydimethylsiloxane (PDMS, MW approximately 2000) blocks. It was shown that these polymers exhibited various degrees of micro-phase separation that further influenced their biological performances in vitro. The formulation with diphenylmethane diisocyanate/PTMO/PDMS/2-butene-1,4-diol at a molar ratio of 2: 0.75: 0.5: 1 in synthesis was favorable due to a combination of enhanced mechanical properties, biostability, cellular affinity as well as platelet nonadherence.