Although linear block copolymer assemblies derived from polymerization-induced self-assembly (PISA) have been prepared with a wide variety of structures, examples with hyperbranched block copolymer assemblies have remained elusive. In this work, efficient synthesis and self-assembly of segmented hyperbranched block copolymers (SHBCs) were achieved via reversible addition–fragmentation chain-transfer (RAFT)-mediated dispersion polymerization-induced self-assembly (PISA) using segmented hyperbranched macro-RAFT agents. Two different approaches including the R-RAFT approach and the Z-RAFT approach were employed to synthesize SHBCs with an important structural difference. Using the Z-RAFT approach, the solvophobic block always grows in the inner of SHBCs, allowing the efficient synthesis of colloidally stable SHBC assemblies with a variety of morphologies. Finally, further structural control over SHBCs and morphological control over SHBC assemblies were achieved by combining the R-RAFT approach and the Z-RAFT approach or adding a chain-transfer monomer into the RAFT-mediated PISA. This work not only develops a facile method for the efficient synthesis of SHBCs and SHBC assemblies but also provides important insights into the PISA process of nonlinear block copolymers.

Organic field-effect transistors (OFETs) with polymer charge-trapping dielectric, which exhibit many advantages over Si-based memory devices such as low cost, light weight, and flexibility, still suffer challenges in practical application due to the unsatisfied endurance characteristics and even the lack of fundamental of behind mechanism. Here, we revealed that the degradation of endurance characteristics of pentacene OFET with poly(2-vinyl naphthalene) (PVN) as charge-storage layer is dominated by the deep hole-traps in PVN by using the photo-stimulated charge de-trapping technique with the fiber-coupled monochromatic-light probes. The depth distribution of hole-traps in PVN film of pentacene OFET is also provided.

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