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PubMed · 10768754

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

D J Martin·L A Warren·P A Gunatillake·S J McCarthy·G F Meijs·K Schindhelm
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Abstract

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.

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Biocompatible MaterialsDimethylpolysiloxanesDrug StabilityElasticityMicroscopy, Electron, ScanningPolyurethanesSiliconesTensile StrengthJournal Article

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BibTeXRIS

D J Martin, L A Warren, P A Gunatillake, S J McCarthy, G F Meijs, K Schindhelm. 2000. Polydimethylsiloxane/polyether-mixed macrodiol-based polyurethane elastomers: biostability.. https://doi.org/10.1016/s0142-9612(99)00271-9

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