| 摘要 |
PROBLEM TO BE SOLVED: To provide a freshness keeping gas permselective membrane having high permselectivity with respect to oxygen and carbon dioxide and capable of setting oxygen permeability, an e-value (carbon dioxide permeability/oxygen permeability) and a glass transition temperature (Tg) to proper values. SOLUTION: The freshness keeping gas permselective membrane is obtained by polymerizing an isocyanate, a polyol such as polyethylene glycol, polypropylene glycol, polytetramethylene glycol, or the like and a silicone type polyol such as modified polysiloxane carbinol or the like and characterized in that the permselectivity to oxygen and carbon dioxide is largely changed within a glass transition temperature range of 0-40 deg.C.
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