The physical aging phenomenon of 6FDA-durene polyimide hollow fiber membranes

Separation of CO2/CH4 through carbon molecular sieve membranes derived from P84 polyimide

“…Two instant challenges facing by current polymer membranes technology are to achieve the high separation properties and maintain its durability in adverse and rigorous environment. Polymeric membranes are suffering from the problems of aging [2][3][4] and plasticization [5][6][7], where the separation performances decline with the passage of time. With response to the limitations of polymeric membranes, inorganic membranes, especially the carbon molecular sieve membranes (CMSMs) have been identified as an alternative candidate for gas separation.…”

The Role of Fluorinated Aryl Ether Moiety in Polyimide-co-etherimide on Gas Transport Properties

“…Among the widely investigated aromatic polyimides, those containing bulky −CF 3 groups, such as 4,4-(hexafluoroisopropylidene) diphthalic anhydride (6FDA), have been studied in detail due to their high permeability and selectivity as well as their higher mechanical and thermal stability. − Meanwhile, 6FDA–durene has been widely studied in our group due to its high performance and easy preparation and upscaling to form hollow fiber membranes. − Therefore, in this study, our objectives are to incorporate the aryl ether containing diamine monomer (2,2-bis­[4-(4-aminophenoxy)-phenyl]­hexafluoropropane, 4BDAF) and generate a series of novel fluorinated polyimide- co -etherimides based on 6FDA–durene. 4BDAF was selected as the monomer to form the copolymers as it contains two aryl ether groups and additional bulky −CF 3 groups which may hinder the permeability reduction due to the intersegmentally mobile aryl ether group .…”

Selective removal of butanol from aqueous solution by pervaporation with a PIM-1 membrane and membrane aging

“…Generally, polymer aging is manifested by changes in the material properties (e.g., density, gas permeability, etc.). It corresponds to a slow and spontaneous rearrangement of the polymer from the non-equilibrium state of the material, towards thermodynamic equilibrium [21][22][23][24][25][26][27][28][29][30].…”