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Highlights: Alkyl-tailored Y-SMAs named YR-SeNF series with near-infrared absorption, different molecular crystallinity and self-assembly abilities are developed. The related organic solar cells (OSCs) with an active layer processed from halogen-free solvents and spin-coating-free technologies achieve a ~ 19% efficiency. Ternary OSCs offer a robust operating stability under MPP tracking and well-keep > 80% of the initial efficiency for even over 400 h. Power-conversion-efficiencies (PCEs) of organic solar cells (OSCs) in laboratory, normally processed by spin-coating technology with toxic halogenated solvents, have reached over 19%. However, there is usually a marked PCE drop when the blade-coating and/or green-solvents toward large-scale printing are used instead, which hampers the practical development of OSCs. Here, a new series of N-alkyl-tailored small molecule acceptors named YR-SeNF with a same molecular main backbone are developed by combining selenium-fused central-core and naphthalene-fused end-group. Thanks to the N-alkyl engineering, NIR-absorbing YR-SeNF series show different crystallinity, packing patterns, and miscibility with polymeric donor. The studies exhibit that the molecular packing, crystallinity, and vertical distribution of active layer morphologies are well optimized by introducing newly designed guest acceptor associated with tailored N-alkyl chains, providing the improved charge transfer dynamics and stability for the PM6:L8-BO:YR-SeNF-based OSCs. As a result, a record-high PCE approaching 19% is achieved in the blade-coating OSCs fabricated from a green-solvent o-xylene with high-boiling point. Notably, ternary OSCs offer robust operating stability under maximum-power-point tracking and well-keep > 80% of the initial PCEs for even over 400 h. Our alkyl-tailored guest acceptor strategy provides a unique approach to develop green-solvent and blade-coating processed high-efficiency and operating stable OSCs, which paves a way for industrial development. [ABSTRACT FROM AUTHOR]

ABSTRACT Solution self-assembly of amphiphilic 'rod-coil' copolymers, especially linear block copolymers and graft copolymers (also referred to as polymer brushes), has attracted considerable interest, as replacing one of the blocks of a coil-coil copolymer with a rigid segment results in distinct self-assembly features compared with those of the coil-coil copolymer. The unique interplay between microphase separation of the rod and coil blocks with great geometric disparities can lead to the formation of unusual morphologies that are distinctly different from those known for coil-coil copolymers. This review presents the recent achievements in the controlled self-assembly of rod-coil linear block copolymers and graft copolymers in solution, focusing on copolymer systems containing conjugated polymers, liquid crystalline polymers, polypeptides, and polyisocyanates as the rod segments. The discussions concentrate on the principle of controlling over the morphology of rod-coil copolymer assemblies, as well as their distinctive optical and optoelectronic properties or biocompatibility and stimuli-responsiveness, which afford the assemblies great potential as functional materials particularly for optical, optoelectronic and biological applications. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017, 55, 1459-1477 [ABSTRACT FROM AUTHOR]

A well-defined thermoresponsive poly(ethylene glycol)-block-poly(N-isopropylacrylamide)-block-poly(ε-caprolactone) (PEG43-b-PNIPAM82-b-PCL87) triblock copolymer was synthesized by combination of atom transfer radical polymerization (ATRP), ring-opening polymerization (ROP), and click chemistry. The synthesis included the four steps, and all the structures of the polymers were determined. The thermoresponsive triblock copolymer can disperse in water at room temperature to form core–shell–corona micelles with the hydrophobic PCL block as core, the thermoresponsive PNIPAM block as shell, and the hydrophilic PEG block as corona. At temperatures above the lower critical solution temperature (LCST) of the PNIPAM block, the PNIPAM chains gradually collapse on the PCL core to shrink the size and change the structure of the resultant core–shell–corona micelles with temperature increasing. [ABSTRACT FROM AUTHOR]