Synthesis and characterization of new aromatic poly(ether imide)s and their gas transport properties

A series of processable fluorinated poly(ether imide)s (Pis) were synthesized by reacting a diamine monomer, 1,4-bis-[{2'-trifluromethyl 4'-(4 ''-aminophenyl)phenoxy}] benzene (HQA) with six different aromatic dianhydrides e.g., BPADA, 6FDA, ODPA, BPDA, BTDA and PMDA. The polyimides showed reasonably high glass-transition temperature (T-g up to 280 degrees C) and high thermal stability (T-d,T-10 up to 558 degrees C). The membranes of these polymers showed tensile strength up to 107 MPa with elongation at break up to 15%, low water absorption (0.61-1.29%), low dielectric constant (2.10-3.13 at 1 MHz) and high optical transparency (lambda(cut-off) up to 466 nm). The PI membrane prepared from 6FDA exhibited high permeability and permselectivity for O-2/N-2 (P-O2 = 11.8 and P-O2/P-N2 = 9.44) gas pair which eventually surpassed the present upper boundary limit drawn by LM. Robeson. (C) 2013 Elsevier Ltd. All rights reserved.