The invention relates to novel polymerisable thieno[3,2-b]thiophenes, to their use as semiconductors or charge transport materials, in optical, electro-optical or electronic devices like for example liquid, crystal displays, optical films, organic field effect transistors (FET or OFET) for thin film transistor liquid crystal displays and integrated circuit devices such as RFID tags, electroluminescent devices in flat panel displays, and in photovoltaic and sensor devices, and to field effect transistors, light emitting devices or ID tags comprising the novel compounds.