ISSN:
0021-9304
Keywords:
Chemistry
;
Polymer and Materials Science
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Medicine
,
Technology
Notes:
The interpenetrating polymer networks (IPNs) of polyurethane (PU) and 2-hydroxyethyl methacrylate (MEHA)-terminated polyurethane (HPU) were prepared by solution polymerization. PU prepolymer was synthesized from 4,4-diphenyl methane diisocyanate (MDI) and poly(propylene oxide) glycol (PPG). HPU prepolymer was synthesized from MDI, poly(tetramethylene oxide) glycol and HEMA. Dynamic mechanical analysis showed that the resultant IPN membranes have good compatibility between their constituents. As the HPU content increased, the tensile strength of the IPNs first increased and then decreased. For the highest tensile strength, the optimum HPU content was about 25 wt %. The value of surface tension of IPNs varied from 44.4 to 50.5 dyne/cm, and polarity ranged from 0.59 to 0.91. The relative index of platelet adhesion (RIPA) of the IPN membranes was measured by the dynamic thrombosis test at constant shaking speed and temperature. By the criteria of this test, the IPN membranes with HPU content of about 25 wt % have the minimum platelet adhesion. When measured by the angular dependent ESCA technique on the surface of IPN samples, the variation in the RIPA correlated to the change in the surface soft segment to hard segment ratio. Higher HPU content resulted in more migration of soft segments toward the surface. The platelet adhesion was observed to be minimized when the surface O/N ratio was around 12. © 1997 John Wiley & Sons, Inc.
Additional Material:
14 Ill.
Type of Medium:
Electronic Resource
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