A New Postfunctional Approach To Prepare Second-Order Nonlinear Optical Polyphophazenes Containing Sulfonyl-Based Chromophore

A TCBD-based AB2-type second-order nonlinear optical hyperbranched polymer prepared by a facile click-type postfunctionalization

A double click-type postfunctionalization strategy was successfully designed to prepare an AB₂-type hyperbranched polymer containing highly polarizable tetracyanobutadienyl (TCBD)-based nonlinear optical chromophores.

A series of dendronized hyperbranched polymers with dendritic chromophore moieties in the periphery: convenient synthesis and large nonlinear optical effects

Excellent optical transparency and NLO coefficients were achieved by introducing dendritic chromophore moieties to the periphery of dendronized hyperbranched polymers.

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 utilization of post-synthetic modification in opto-electronic polymers: an effective complementary approach but not a competitive one to the traditional direct polymerization process

By presenting some typical examples, the recent progress of opto-electronic polymers is reviewed, which were only accessible from the post-synthetic modification strategy.

4',4',6',6'-Tetra-chloro-2-(6-methyl-pyridin-2-yl)-1H,2H-spiro-[naphtho-[1,2-e][1,3,2]oxaza-phosphinine-3,2'-[1,3,5,2,4,6]tri-aza-triphosphinine]

The title compound, C17H14Cl4N5OP3, is a spiro-phosphazene derivative with bulky naphthalene and pyridine rings. The phosphazene and the six-membered N/O rings are in flattened-boat and twisted-boat conformations, respectively. The naphthalene ring system and the pyridine ring are oriented at a dihedral angle of 18.06 (8)°. In the crystal, weak π-π stacking between the pyridine rings and between the pyridine rings and the naphthalene ring system [centroid-centroid distances = 3.594 (2) and 3.961 (2) Å, respectively] occur. Weak C-H⋯π inter-actions are also observed. These interactions link the molecules into a three-dimensional supramolecular network.

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.

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.

Dendronlike main-chain nonlinear optical (NLO) polyurethanes constructed from "H"-type chromophores: synthesis and NLO properties

For the first time, a series of dendronlike main-chain polyurethanes have been successfully designed and synthesized, in which different isolation groups with different sizes were introduced to modify the subtle structure of the used "H"-type chromophores, according the concept of "suitable isolation groups". Thanks to the advantages of "H"-type chromophores and the introduced suitable isolation group, all of the polymers demonstrated large NLO effects, good processability, improved optical transparency, and thermal stability. The obtained experimental results indicated that the utilization of "H"-type chromophores might be a promising choice to efficiently translate the large beta values of the organic chromophores into high macroscopic NLO activities of polymers.