The graft-through synthesis of Janus graft block copolymers (GBCPs) from branched macromonomers composed of various combinations of homopolymers is presented. Self-assembly of GBCPs resulted in ordered nanostructures with ultra-small domain sizes down to 2.8 nm (half-pitch). The grafted architecture introduces an additional parameter, the backbone length, which enables control over the thermomechanical properties and processability of the GBCPs independently of their self-assembled nanostructures. The simple synthetic route to GBCPs and the possibility of using a variety of polymer combinations contribute to the universality of this technique.

The synthesis of a carbazole-derived, well-defined ladder polymer was achieved under thermodynamic control by employing reversible ring-closing olefin metathesis.

Organic field-effect transistors (OFETs) are receiving increasing attention due to their intriguing advantages such as flexibility, low cost and solution processibility. Development of organic conjugated polymers with balanced ambipolar carrier transportation operated under ambient conditions, in particular, is considered to be one of the central issues in OFETs. In this work, 3,7-bis((E)-2-oxoindolin-3-ylidene)-3,7-dihydrobenzo[1,2-b:4,5-b']difuran-2,6-dione (BDOPV) unit as a good acceptor unit was copolymerized with three donor moieties, thieno[3,2-b]thiophene (TT), benzo[1,2-b:4,5-b']dithiophene (BDT) and benzo[1,2-b:4,5-b']diselenophene (BDSe), to construct three donor-acceptor (D-A) conjugated polymers, BDOPV-TT, BDOPV-BDT and BDOPV-BDSe. Photophysical and electrochemical properties of all the polymers were characterized. The fabrication of OFETs using three polymers as the active layers demonstrated that all the three polymers showed balanced ambipolar transport property tested under ambient conditions, which is of great importance in complementary circuits. In particular, both electron and hole mobilities of BDOPV-TT were achieved above 1 cm 2 V −1 s −1 under ambient conditions (1.37 and 1.70 cm 2 V −1 s −1 , respectively), showing great potential in balanced ambipolar OFETs.

Active conformational control is realized in a conjugated system using intramolecular hydrogen bonds to achieve tailored molecular, supramolecular, and solid-state properties. The hydrogen bonding functionalities are fused to the backbone and precisely preorganized to enforce a fully coplanar conformation of the π-system, leading to short π-π stacking distances, controllable molecular self-assembly, and solid-state growth of one-dimensional nano-/microfibers. This investigation demonstrates the efficiency and significance of an intramolecular noncovalent approach in promoting conformational control and self-assembly of organic molecules.

Ladder-type conjugated molecules with a low band gap and low LUMO level were synthesized through an N-directed borylation reaction of pyrazine-derived donor-acceptor-donor precursors. The intramolecular boron-nitrogen coordination bonds played a key role in rendering the rigid and coplanar conformation of these molecules and their corresponding electronic structures. Experimental investigation and theoretical simulation revealed the dynamic nature of such coordination, which allowed for active manipulation of the optical properties of these molecules by using competing Lewis basic solvents.

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A donor-acceptor-donor molecule, , showed typical twist intramolecular charge transfer at the excited state and piezochromic property. XRD, DSC and computational researches revealed that the collapse of the crystalline structure upon applying pressure caused the piezochromic phenomenon, while the fluorescence was recovered by heating and solvent fuming.

Latent H-bonds in conjugated statistical copolymers rendered semiconducting thin films resistant to solvent immersion.