Synthesis and air separation of soluble terpolymers from aniline, toluidine, and xylidine

A series of terpolymers were synthesized by oxidative polymerization of ani line, o-toluidine, and 2,3-xylidine with three monomer ratios using ammoniu m persulfate as an oxidant in two acidic media. The yield and intrinsic vis cosity of the terpolymers were studied by changing the polymerization tempe rature and medium. The resulting terpolymers were characterized by H-1-NMR, wide-angle X-ray diffraction, differential scanning calorimetry, thermogra vimetry, and constant pressure-variable volume methods. The results showed that the terpolymers are amorphous and exhibit enhanced solubility, high th ermostability, and high char yield, greater than 35 wt % at 900 degreesC in nitrogen. A blend membrane of the terpolymer with ethyl cellulose shows go od air-separation ability. (C) 2001 John Wiley & Sons, Inc.