| 摘要 |
PURPOSE: To selectively separate an arom. compd. from a satd. compd. by forming a polyurea/urethane membrane specified in the respective characteristic values of a urea index, arom. carbon content, functional group density and C=O/NH ratio. CONSTITUTION: The polyurea/urethane membrane having the urea index of 20 to 100%, the arom. carbon content of at least 15 mole %, the functional group density of >=10 per 100 g polymer and the C=O/NH ratio of <8 is formed. The polyurea/urethane membrane may be obtd. by reacting a dihydroxyl or polyhydroxyl compd. with an arom., an alkyl arom. or an arom. diisocyanate or polyisocyanate and a low mol.wt. chain extender. A mixture composed of the arom. compd. and the non-arom. compd. is supplied to the resulted polyurea/ urethane membrane, by which the arom. compd. is efficiently separated. |
