Key Laboratory of Synthetic and Self-Assembly Chemistry for Organic Functional Molecules, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032, China
Prof. Dr. Xiaoyu Huang
Key Laboratory of Synthetic and Self-Assembly Chemistry for Organic Functional Molecules, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032, China
Graft copolymers with a large number of side chains chemically attached onto a linear backbone are endowed with unusual properties thanks to their confined and compact structures, including wormlike conformation, compact molecular dimensions and notable chain end effects. Growing attention has been paid to these interesting macromolecules due to their importance in understanding the correlation between architectures and properties, as well as their potential applications. To date, the synthesis and properties of graft copolymers in both solution and bulk have been extensively investigated, along with their applications. In this tutorial review, recent advances in synthetic approaches towards the construction of well-defined graft copolymers are discussed in detail and applications of these interesting macromolecules are highlighted by selected examples.
We report the preparation of a series of fiber-like micelles of narrow length distribution with an oligo(p-phenylenevinylene) (OPV)-core and a poly(N-isopropylacrylamide) (PNIPAM) corona via two different crystallization-driven self-assembly (CDSA) strategies. The average length Ln of these micelles can be varied up to 870 nm by varying the temperature in self-seeding experiments. In addition, seeded growth was employed not only to prepare uniform micelles of controlled length, but also to form fiber-like A-B-A triblock comicelles with an OPV-core.
Covalent organic frameworks (COFs) have attracted increasing interest for their use as electrode materials for lithium-ion batteries (LIBs) by virtue of their microporous crystalline structures and robust networks. However, the tightly stacked bulk COFs and their intrinsic low conductivity inevitably result in an inefficient utilization of redox-active sites so as to lower the electrochemical performance. Herein, we proposed a general strategy to improve the energy storage capability of polyimide (PI)-COF based cathode materials, which included the decrease of their stacked layer numbers to a few layers via a mechanical milling method for the efficient utilization of redox-active sites and the incorporation of few-layer COF sheets with chemically reduced graphene oxide (rGO) to increase the charge transfer. The excellent electrochemical performance of the composite few-layer PI-COFs with rGO cathodes indicated that reducing the layer number of COFs and incorporating rGO may pave the way for the successful development of COF-based organic electrodes for LIBs.
Asymmetric molecular brushes emerge as a unique class of nanostructured polymers, while their versatile synthesis keeps a challenge for chemists. Here we show the synthesis of well-defined asymmetric molecular double-brushes comprising two different side chains linked to the same repeat unit along the backbone by one-pot concurrent atom transfer radical polymerization (ATRP) and Cu-catalyzed azide/alkyne cycloaddition (CuAAC) reaction. The double-brushes are based on a poly(Br-acrylate-alkyne) homopolymer possessing an alkynyl for CuAAC reaction and a 2-bromopropionate initiating group for ATRP in each repeat unit. The versatility of this one-shot approach is demonstrated by CuAAC reaction of alkynyl/poly(ethylene oxide)-N3 and ATRP of various monomers. We also show the quantitative conversion of pentafluorophenyl ester groups to amide groups in side chains, allowing for the further fabrication of diverse building blocks. This work provides a versatile platform for facile synthesis of Janus-type double-brushes with structural and functional control, in a minimum number of reactions.