Segmented Polyether Polyurethane

A Polyester and a Polyurethane. A segmented polyether-polyurethane sample (UET46-1) was synthesized in one step from 4-4 diphenyl methane diisocyanate, 1-4 butanediol and poly(tetra-methylene ether)glycol ... 

Figure 4. Measured e spectra at 24°C for O, a segmented polyether-polyurethane (UET46-1) and , a segmented polyether-polyester (H49). Measurements were made with the steady-state response dielectric spectrometer.

Figure 8. Measured polarization decay functions at 24°C for three segmented polyether-polyurethanes. HET49-1 is tested after annealing at 80°C followed by stabilization at 24°C. UET48-1 is tested with and without annealing. The decay function is the depolarization current density normalized by the electric field value...

Figure 9. Transformed e spectra at 24°C for three segmented polyether-polyurethanes. Key O, UET48-1 (80°C anneal) , VET48-1 and A, HET49-1...

From their previous experience in the synthesis of polyurethanes for dialysis membranes, Lyman and Associates(5.) also introduced a segmented polyether polyurethane which has shown excellent thromboresistance. (A)... 

In 1968, Ontario Research Foundation developed a series of segmented polyether polyurethanes as polymer membrane materials for reverse cosmosis, ultrafiltration and hemodialysis. The elastomers of recent implant studies are polyurea-urethanes( .) with modification of the synthesis limited to only one variable— the chain length of the polyether component. 

Segmented polyether polyurethanes are widely studied biomaterials that can be conceptualized (1-3) as a virtual network in which the continuous phase contains the polyether chain molecules. These chain molecules are tied at their ends to the molecular, species (diisocyanate, diamine) which serve as junctions by associating into clusters. These clusters of high melting point form the hard-segment phase and are dispersed in the continuous polyether phase. 

Molecular models (2) of the hard-segment phase of segmented polyether polyurethanes tested in the in vitro bead column (4) show a high platelet retention index (p = 0.8) regardless of molecular composition. The variable p is defined as the fraction of platelets in whole citrated human blood entering a test column that are retained on the bead surfaces, averaged for... 

Segmented polyether-polyurethanes Polyurethane-based block copolymers and blends... 

For many water-insoluble polymers the Immune response, if any, is more difficult to evaluate. Recently, Habal and coworkers (]JL) have reported a method to assess the effect of solid implant materials such as silicone, segmented polyether-polyurethane, polyCmethyl methacrylate), and Bioglas using tumor-bearing mice as the experimental model. They have found that the B-cells from the test animals showed a reduced capacity for proliferation when stimulated by mitogens as compared to the controls. The results demonstrate once again that even the relatively biocompatible solid polymers may have a measurable effect on the immune system. 

Wang CB, Cooper SL. Morphology and properties of segmented polyether polyurethan-eureas. Macromolecules 1983 16(5) 775-86. 

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