Uncatalyzed synthesis, thermal and mechanical properties of polyurethanes based on poly(epsilon-caprolactone) and 1,4-butane diisocyanate with uniform hard segment

Biomaterials. 2005 Jul;26(20):4219-28. doi: 10.1016/j.biomaterials.2004.11.005.

Abstract

Polyurethanes based on poly(epsilon-caprolactone) (PCL) (750-2800 g/mol) and 1,4-butane diisocyanate (BDI) with different soft segment lengths and constant uniform hard segment length were synthesized in absence of catalysts for the production of a degradable meniscus scaffold. First the polyesterdiols were endcapped with BDI yielding a macrodiisocyanate with a minimal amount of side reactions and a functionality of 2.0. Subsequently, the macrodiisocyanates were extended with 1,4-butanediol in order to obtain the corresponding polyurethane. The polyurethanes had molecular weights between 78 and 160 kg/mol. Above molar masses of 1900 g/mol of the polyesterdiol crystalline PCL was found while the hard segment showed an increase in melting point from 78 to 122 degrees C with increasing hard segment content. It was estimated that the percentage crystallinity of the hard segment varied between 92 and 26%. The Young's modulus varied between 30 and 264 MPa, the strain at break varied between 870 and 1200% and tear strengths varied between 97 and 237 kJ/m2.

Publication types

  • Evaluation Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Absorbable Implants*
  • Biocompatible Materials / analysis
  • Biocompatible Materials / chemistry*
  • Butanes / analysis
  • Butanes / chemistry*
  • Catalysis
  • Compressive Strength
  • Elasticity
  • Hardness
  • Materials Testing
  • Molecular Weight
  • Nitriles / analysis
  • Nitriles / chemistry*
  • Polyesters / analysis
  • Polyesters / chemistry*
  • Stress, Mechanical
  • Surface Properties
  • Temperature
  • Transition Temperature

Substances

  • 1,4-butane diisocyanate
  • Biocompatible Materials
  • Butanes
  • Nitriles
  • Polyesters
  • polycaprolactone