Synthesis, Self‐assembly, and Fluorescence Application of Bottlebrush Polyfluorene‐g‐Polycaprolactone with Conjugated Backbone and Crystalline Brushes

Abstract

A series of bottlebrush copolymers with conjugated backbone and crystalline branch chains, polyfluorene‐g‐polycaprolactone (PF‐g‐PCL), are synthesized by combining Suzuki cross‐coupling polymerization and cationic ring‐opening polymerization. The PF‐g‐PCLs are prepared to self‐assembled in solution and thin film. Due to the J‐type aggregation of the polyfluorene main chains, the self‐assembly spherical micelles have been observed. Meanwhile, in film, they exhibited self‐assembly ringed spherulites because of the PF microregions in the bottlebrush copolymer. As a result of the interruption of PCL side chains, the aggregation tendency of PF main chains is weakened. And both the polymer solution and solid can overcome the aggregation‐caused quenching to provide more pronounced fluorescence. Especially, owing to the good processability of the PF‐g‐PCL, as a fluorescent ink for different substrates, they can easily be prepared as high‐brightness fluorescent films that are invisible under ambient light.

Fluorescence-readout as a powerful macromolecular characterisation tool

“…Controlled polymerisation techniques, including living anionic polymerisation and RDRP, in combination with various linking reactions, offer exceptional opportunities to access a variety of well-dened block copolymers, including linear, star, gra and cyclic architectures, greatly enriching the chemistry and functionality of selfassembled systems. [250][251][252][253][254] Self-assembly of block copolymers can be conducted in bulk or in solution. Bulk self-assembly is usually induced by thermal or solvent annealing, where microphase separation, driven by thermodynamic incompatibilities between polymers, forms a wide range of nanostructures, such as spheres, cylinders, lamellae and gyroids.…”

Insights into the β‐phase of polyfluorene: characterization, regulation, and mechanism

“…So far, in order to obtain PFO with high β‐phase content, various measures have been taken to the solvent, including reducing the solvent temperature, 72 adding the poor solvent, 73 adjusting the poor solvent concentration, 74 etc. But in fact, these means change the solubility of the solvent and achieve the purpose of changing the content of β phase.…”

Controlled Synthesis, Chiral Assembly, and Circularly Polarized Luminescence of Poly(Phenyl Isocyanide)‐Block‐Polyfluorene Copolymers

“…[18] Moreover, PFs can also be modified through copolymerization strategy, and various PF-containing copolymers have been investigated. [19][20][21] However, copolymers consisting of PF with chiral polymers are very limited, although they may exhibit exciting functionality, such as circularly polarized luminescence (CPL), that can be applied for constructing novel optoelectronic devices.…”