6FDA-TMPDA

Figure 11.16 The time dependent effect of addition of hexane on the permeability of CO2 in 6FDA-TMPDA from a methane (90%) and carbon dioxide (10%) gas mixture. Reprinted with permission from Ind Eng Chem Res., The effect of hydrocarbons on the separation of carbon dioxide from methane through a polyimide gas separation membrane by Hasan, R., C. A. Scholes, C. W. Stevens and S. E. Kentish, 48, 5415-5419, Copyright (2009) American Chemical Society...

Table 3.8 Physical Properties of 6FDA-TMPDA/DAT Copolyimides...

Table 3.9 Permeability Coefficients and Permselectivity of 6FDA-TMPDA/DAT Polyimides at 35 °C and 0.2 MPa...

Figure 3.7 Performance of 6FDA-TMPDA/2,6-DAT copolyimides compared with (a) O2-N2 tradeoff limit and...

The etherification reaction of polyimides is similar to the process of the imide ringopening reaction. It was demonstrated for the reaction of polyimides with primary diamine and epoxy agents [57,58] (for example, for 6FDA-TeMPD polyimides and tet-raglycidyldiaminodiphenylmethane (TGDDM), diethyltoluenedianune (DETDA) [57], TMPDA, 1,3-phenylenediamine (PDA) and4,4 -(9-fluorenylidene)dianiline (FDA) [58]). The density of polymers and crosslink concentration inaeased with the increase in epoxy content. 

A systematic study of the synthesis, characterization, and gas transport properties of novel 6FDA-based copolyimides was performed by Yuan and co-workers [182]. They varied the diamine ratios, namely, 2,4,6-trimethyl-1,3-phenylenediamine (TMPDA)/2,6-... 

---