Polydimethylsiloxane/polyether-mixed macrodiol-based polyurethane elastomers: biostability.

A series of four thermoplastic polyurethane elastomers were synthesized with varying proportions of poly(hexamethylene oxide) (PHMO) and poly(dimethylsiloxane) (PDMS) macrodiols. The macrodiol ratios (by weight) employed were (% PDMS:% PHMO) 100:0, 80:20, 50:50 and 20:80. The weight fraction of macrodiol in each polymer was fixed at 60%. The mixed macrodiols were reacted with 4,4'-methylenediphenyl diisocyanate (MDI) and 1,4-butanediol (BDO) chain extender. The biostability of these polymers was assessed by strained subcutaneous implantation in sheep for three months followed by microscopic examination. Pellethane 2363-80A and 2363-55D were employed as control materials. The mechanical properties of the polymers were tested and discussed along with the biostability results. The results showed that soft, flexible PDMS-based polyurethanes with very promising biostability can be successfully produced using the mixed macrodiol approach. The formulation with 80% PDMS macrodiol produced the best result in terms of a combination of flexibility, strength and biostability.

[1]  S. Cooper,et al.  Synthesis, characterization and ex vivo evaluation of poly-dimethylsiloxane polyurea-urethanes , 1994 .

[2]  James M. Anderson,et al.  Polyurethane Elastomer Biostability , 1995, Journal of biomaterials applications.

[3]  J. Santerre,et al.  Application of macromolecular additives to reduce the hydrolytic degradation of polyurethanes by lysosomal enzymes. , 1997, Biomaterials.

[4]  J. Santerre,et al.  The effect of phospholipids on the biodegradation of polyurethanes by lysosomal enzymes. , 1997, Journal of biomaterials science. Polymer edition.

[5]  A. Hiltner,et al.  Cellular interactions with biomaterials: in vivo cracking of pre-stressed Pellethane 2363-80A. , 1990, Journal of biomedical materials research.

[6]  C. Capone,et al.  Biostability of a Non-Ether Polyurethane , 1992, Journal of biomaterials applications.

[7]  H. Planck,et al.  Polyurethanes in Biomedical Engineering , 1984 .

[8]  Arnold Lustiger.  Understanding Environmental Stress Cracking in Polyethylene , 1998 .

[9]  S. Cooper,et al.  Blood-contacting properties of polydimethylsiloxane polyurea-urethanes. , 1994, Biomaterials.

[10]  M Szycher,et al.  In vivo Testing of a Biostable Polyurethane , 1991, Journal of biomaterials applications.

[11]  P. Urbański,et al.  Glass wool-H2O2/CoCl2 test system for in vitro evaluation of biodegradative stress cracking in polyurethane elastomers. , 1995, Journal of biomedical materials research.

[12]  J M Anderson,et al.  In vivo biocompatibility and biostability of modified polyurethanes. , 1997, Journal of biomedical materials research.

[13]  W S Pierce,et al.  Segmented Polyurethane: A New Elastomer for Biomedical Applications , 1967, Science.

[14]  Darren J. Martin,et al.  The effect of average soft segment length on morphology and properties of a series of polyurethane elastomers. I. Characterization of the series , 1996 .

[15]  Darren J. Martin,et al.  The influence of composition ratio on the morphology of biomedical polyurethanes , 1999 .

[16]  R. Guidoin,et al.  Chemical stability of polyether urethanes versus polycarbonate urethanes. , 1997, Journal of biomedical materials research.

[17]  Darren J. Martin,et al.  The effect of average soft segment length on morphology and properties of a series of polyurethane elastomers. II. SAXS‐DSC annealing study , 1997 .

[18]  J. Santerre,et al.  Neutrophil-mediated degradation of segmented polyurethanes. , 1995, Biomaterials.

[19]  D. Williams,et al.  Mechanisms of biodegradation of implantable polymers. , 1992, Clinical materials.

[20]  J. Santerre,et al.  Differential synthesis of cholesterol esterase by monocyte-derived macrophages cultured on poly(ether or ester)-based poly(urethane)s. , 1998, Journal of biomedical materials research.

[21]  A. M. Reed,et al.  A Solution Grade Biostable Polyurethane Elastomer: ChronoFlex® AR , 1994, Journal of biomaterials applications.

[22]  Darren J. Martin,et al.  Effect of soft-segment CH2/O ratio on morphology and properties of a series of polyurethane elastomers , 1996 .

[23]  S. Sakurai,et al.  Structure characterization of polyurethanes containing poly(dimethylsiloxane) , 1991 .

[24]  J. Santerre,et al.  Enzyme-biomaterial interactions: effect of biosystems on degradation of polyurethanes. , 1993, Journal of biomedical materials research.

[25]  H. Griesser.  Degradation of polyurethanes in biomedical applications—A review , 1991 .

[26]  J. Shin,et al.  Synthesis and characterization of poly(siloxane‐urethane)s , 1992 .