Ph.D. Student, Polymer Research, AO/ASIF Research Institute, Davos,
Professor and Head, Polymer Research, AO/ASIF Research Institute, Davos,
Pages: 19 Published: Jan 2000
Biodegradable polyurethanes with various hydrophilic-to-hydrophobic ratios and potential application for nonadhesive barriers in surgery and/or scaffolds for tissue engineering and bone substitutes were synthesized from polycaprolactone diol, mixtures of polycaprolactone and polyethylene oxide diols, hexamethylene- and/or isophorone diiscocyanates, and 1,4-butane diol or 2-amino-1-butanol chain extenders. The polymers had viscosity-average molecular weights in the range of 24.000 to 130.000 dalton, tensile strengths at break of 4 to 60 MPa, Young's moduli from 7 to 72 MPa, elongation at break of 100 to 950%, and glass transition temperatures in the range of-116 to -41°C. The affinity of polymers towards proteins varied depending on the type of polyol and the chain extender used. The adsorption of proteins from whole blood was highest for the materials based on poly(ε-caprolactone) and those containing 2-amino-1-butanol chain extender. There was no protein adsorption on materials based on mixtures of caprolactone and ethylene oxide polyols independent of the poly(ethylene oxide) molecular weight and the chain extender used. The polymers could be processed into three-dimensional porous scaffolds (membranes and sponges) using a phase-inverse process from solutions consisting of a solvent-nonsolvent system and/or with salt crystals additives.
biodegradable materials, polyurethanes, polymer synthesis, protein adsorption, nonadhesive barriers, porous scaffolds
Paper ID: STP15299S