Main chain dendronized hyperbranched polymers: convenient synthesis and good second-order nonlinear optical performance

By using low generation dendrimers as macromonomers, two main chain dendronized hyperbranched polymers, with good comprehensive nonlinear optical performance, were prepared conveniently with satisfying yields through a one-pot “A₃ + B₂” approach.

The integration of an “X” type dendron into polymers to further improve the comprehensive NLO performance

Three polymers were designed and synthesized, by utilizing an “X” type dendrimer containing five nitro-based azo chromophore moieties, which exhibit good processability and good nonlinear optical performance, especially for NLO thermostability.

A study of two thermostable NLO chromophores with different π-electron bridges using fluorene as the donor

Chromophore C2 (below) has a better electrooptic performance than chromophore C1 (above).

Facile bromine-termination of nonlinear optical chromophore: remarkable optimization in photophysical properties, surface morphology and electro-optic activity

This paper describes how a small molecular structure modification can enhance the microscopic and macroscopic properties of chromophore.

Hyperbranched polymers: advances from synthesis to applications

This review summarizes the advances in hyperbranched polymers from the viewpoint of structure, click synthesis and functionalization towards their applications in the last decade.

Functional hyperbranched polymers with advanced optical, electrical and magnetic properties

This review summarizes the recent progress in functional HBPs and their application in optics, electronics and magnetics, including light-emitting devices, aggregation-induced emission materials, nonlinear optical materials, chemosensors, solar cells, magnetic materials, etc., and provides outlooks for further exploration in the field.

The influence of pentafluorophenyl groups on the nonlinear optical (NLO) performance of high generation dendrons and dendrimers

With the aim to make the influence of pentafluorophenyl groups in the periphery of high generation dendrons and dendrimers on their NLO performance clearly, some NLO dendrons and dendrimers with different chromophore moieties or different end-capped groups were carefully designed and investigated in detail. The results demonstrated that some strong Ar-Ar^F interactions between the pentafluorophenyl groups in the periphery and the normal phenyl rings of the donors, could influence the topological structures of dendrons or dendrimers, and then affect their NLO performance. Furthermore, the optical transparency and the stability of the dendrons and dendrimers with pentafluorophenyl groups as end-capped moieties were all improved, in comparison with normal dendrons and dendrimers containing phenyl ones as the end-capped groups.

Synthesis and characterization of a novel second-order nonlinear optical chromophore based on a new julolidine donor

A new chromophore was synthesized and the hyperpolarizability can be effectively translated into large electro-optic coefficients in poled polymers.

Comparison of nonlinear optical chromophores containing different conjugated electron-bridges: the relationship between molecular structure-properties and macroscopic electro-optic activities of materials

In electro-optic (EO) materials, realization of large EO coefficients for organic EO materials requires the simultaneous optimization of chromophore first hyperpolarizability, acentric order, molecular shape etc.

Dendrimers with large nonlinear optical performance by introducing isolation chromophore, utilizing the Ar/ArF self-assembly effect, and modifying the topological structure

By the combination of divergent and convergent approach, a new series of NLO dendrimers (G1-PFPh-NS-GL to G3-PFPh-NS-GL) was conveniently prepared with satisfied yields through the powerful "click chemistry" reaction, in which perfluoroaromatic rings were introduced in the periphery, two types of chromophores were arranged with regular AB structure, and their topological structure was improved to a more spherical shape. All the dendrimers demonstrated good processability, and G1-PFPh-NS-GL exhibited the highest NLO effect of 221 pm/V among the three dendrimers.

From nitro- to sulfonyl-based chromophores: improvement of the comprehensive performance of nonlinear optical dendrimers

Through the combination of the divergent and convergent approaches, coupled with the utilization of the powerful Sharpless "click-chemistry" reaction, two series of sulfonyl-based high-generation NLO dendrimers were conveniently prepared with high purity and in satisfactory yields. Thanks to the perfect three-dimensional (3D) spatial isolation from the highly branched structure and the isolation effect of the exterior benzene moieties and the interior triazole rings, these dendrimers exhibited large second harmonic generation coefficient (d33) values up to 181 pm V(-1), which, to the best of our knowledge, is the highest value so far for polymers containing sulfonyl-based chromophore moieties. Meanwhile, compared with the nitro-chromophore-based analogues, their optical transparency and NLO stability were improved in a large degree, due to the lower dipole moment (μ) and the special main-chain structure of sulfonyl-based chromophore in these dendrimers.

Dicyanomethylene-4H-pyran chromophores for OLED emitters, logic gates and optical chemosensors

Dicyanomethylene-4H-pyran (DCM) chromophores are typical donor-π-acceptor (D-π-A) type chromophores with a broad absorption band resulting from an ultra-fast internal charge-transfer (ICT) process. In 1989, Tang et al. firstly introduced a DCM derivative as a highly fluorescent dopant in organic electroluminescent diodes (OLEDs). Integration of ICT chromophore-receptor systems based on DCM chromophores with ion-induced shifts in absorption or emission is a convenient method to perform the logic expression for molecular logic gates. In recent years, various DCM-type derivatives have been explored due to their excellent optical-electronic properties and diverse structural modification. This feature article provides an insight into how the structural modification of DCM chromophores can be utilized for OLED emitters, logic gates and optical chemosensors. In addition, the aggregation-induced-emission (AIE) of DCM derivatives for further optical applications was also introduced.

Synthesis and photophysical investigation of a series of push-pull arylvinyldiazine chromophores

A new series of push-pull arylvinyldiazines has been efficiently prepared by aldol condensation between the appropriate methyldiazine and aromatic aldehyde. The optical absorption and emission properties of these chromophores were studied in different solvents and media. These compounds act as polarity sensors with a strong positive emission solvatochromism. This behavior suggests a highly polar emitting state, which is characteristic of compounds that undergo an internal charge transfer upon excitation. These molecules also exhibit halochromic properties and are potential colorimetric and luminescence pH sensors. The second-order nonlinear properties have been investigated for some of the compounds, and large and positive μβ are obtained, in particular, for pyrimidine derivatives.

New hyperbranched polytriazoles containing isolation chromophore moieties derived from AB4 monomers through click chemistry under copper(I) catalysis: improved optical transparency and enhanced NLO effects

By modifying a synthetic procedure, two new hyperbranched polytriazoles (HP1 and HP2) containing isolation chromophores were synthesized successfully through click chemistry reactions under copper(I) catalysis. For the first time, these two polymers were derived from an AB(4)-type monomer, although they contain different end-capping chromophores. They are soluble in normal polar organic solvents and are well characterized. Thanks to the presence of the isolation chromophore, the two polymers demonstrate good nonlinear optical (NLO) properties and optical transparency, making them promising candidates for practical applications.