abstract |
A polyimide oligomer has the formula (I) wherein G is a group having a valence of t, each Q, M, D, and V are as defined herein, each R is independently the same or different, and is a C 1-20 divalent hydrocarbon, a C 1-20 alkylene-X, or a C 6-30 arylene-X wherein -X is -O-M, -C(O)O-M, -OC(O)O-M, -S-M, -S(O) 2 -M, -S(O) 3 -M, -OS(O) 3 -M, or -OP(O) 3 -M, and wherein M is a cation, preferably Na, K, Cs, Mg, Ca, Ti, Zr, Cr, Bi, Mn, Fe, Co, Ni, Cu, Zn, Cd, Ge, B, Al, Ga, In, Sn, Pb, As, Sb, ammonium, phosphonium, imidazolium, guanidinium, or pyridinium, q is 0 or 1, m is 0 or 1, d is 0 or 1, p is 1 or 2, t is 1 to 6, and each n is independently the same or different, and is 1 to 1,000, provided that the total of all values of n is greater than 4. |