(3E, 8E)-3, 8-Bis(2-oxoindolin-3-ylidene)naphtho-[1, 2-b:5, 6-b′]difuran-2, 7(3H, 8H)-dione (INDF) based polymers for organic thin-film transistors with highly balanced ambipolar charge transport characteristics. Issue 70 (27th July 2015)