초록 ▼

Asymmetric gas separation membranes of polymeric materials having selective permeation of at least one gas of a gaseous mixture over that of one or more remaining gases of the gaseous mixture, exhibit improved permeation selectivities for the at least one gas when the asymmetric membranes have been

Asymmetric gas separation membranes of polymeric materials having selective permeation of at least one gas of a gaseous mixture over that of one or more remaining gases of the gaseous mixture, exhibit improved permeation selectivities for the at least one gas when the asymmetric membranes have been contacted on one or both surfaces with an effective amount of a permeation modifier. The permeation modified asymmetric gas separation membrane having an effective amount of permeation modifier added in a non-homogeneous mode and without loss of Tg.

대표청구항 ▼

An improved non-porous asymmetric gas separation membrane comprising: a preformed non-porous asymmetric gas separation membrane material having a separation factor for one gas of a gaseous mixture over that of one or more remaining gases of the gaseous mixture, said membrane material having contacte

An improved non-porous asymmetric gas separation membrane comprising: a preformed non-porous asymmetric gas separation membrane material having a separation factor for one gas of a gaseous mixture over that of one or more remaining gases of the gaseous mixture, said membrane material having contacted on one or both surfaces thereof a permeation modifier in an amount effective to improve the separation factor of the membrane for said one gas over that of said remaining gases but insufficient to cause an appreciable change in the physical properties of said membrane material, said permeation modifier being selected from the formula [Figure] (a) in which n is one to three, R and R1 independently are hydroxy, chloro, bromo, amino, alkylamino, dialkylamino, nitro, alkoxy, hydroalkoxy, hydroxyalkyl, carboalkoxy, carboxyalkoxy, or glycidyloxy, and R2 and R3 independently are hydrogen or alkyl; or the formula [Figure] (b) in which R, R1, R2, and R3 are the same as in formula (a), x is oxygen, sulfur, dithio, carbonyl, alkylene, or cycloalkylene, and n1 and n2 are zero to three with the proviso that the sum n1 and n2 is at least two.