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POLYURETHANES - EFFECT OF CHEMICAL-COMPOSITION ON MECHANICAL-PROPERTIES AND OXYGEN PERMEABILITY
Date
1992-01-01
Author
ULUBAYRAM, K
Hasırcı, Nesrin
Metadata
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A series of polyether urethane films with varying hard/soft segment ratio were synthesized using toluene-2,4-diisocyanate (TDI) and polypropylene glycol (PPG) in order to evaluate them as biomaterials. In order to obtain medical purity the polymerization reactions were carried out in bulk without using any other ingredients such as solvent, catalyst, u.v. absorber, etc. The effects of chemical composition and the presence of the chain extender on some properties were examined. For the samples with higher TDI to PPG ratio, a decrease in ultimate elongation and an increase in tensile strength were observed. Addition of chain extender caused an increase in both. On the other hand, the ultimate elongation increased and tensile strength decreased with an increase in molecular weight of the PPG used. As the chemical compositions are changed by increasing the polyol content, an increase in oxygen permeability is also observed.
Subject Keywords
Polyether polyurethane
,
Mechanical properties
,
Oxygen permeability
,
Biomaterials
URI
https://hdl.handle.net/11511/29947
Journal
POLYMER
DOI
https://doi.org/10.1016/0032-3861(92)90874-v
Collections
Graduate School of Natural and Applied Sciences, Article
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K. ULUBAYRAM and N. Hasırcı, “POLYURETHANES - EFFECT OF CHEMICAL-COMPOSITION ON MECHANICAL-PROPERTIES AND OXYGEN PERMEABILITY,”
POLYMER
, pp. 2084–2088, 1992, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/29947.