Stilbene‐containing polyactylenes: Molecular design, synthesis, and relationship between molecular structure and NLO properties

Abstract

Polyacetylenes (P1–P4) containing different stilbene groups, [(CHC) PhCHCHPhR]n(ROCmH2m+1 (m = 4 (P1), 10 (P2), 16 (P3)), or NO2 (P4)) were designed and synthesized, respectively, using [Rh(nbd)Cl]2 as a catalyst. Their structures and properties were characterized and evaluated by FTIR, 1H‐NMR, 13C‐NMR, GPC, and UV, PL, respectively. The optical limiting and nonlinear optical properties were investigated by using a frequency doubled, Q‐switched, mode‐locked Continuum ns/ps Nd:YAG laser system and their optical limiting mechanism was discussed. It is surprising to see that the stilbene pendants endow the polyacetylenes with a high thermal stability (Td ≥ 270 °C), novel optical limiting properties and large third‐order nonlinear optical susceptibilities (up to 4.61 × 10−10 esu). The optical limiting mechanism is mainly originated from reverse saturable absorption of molecules. In addition, it is found that the polymer with electron accepted NO2 moiety exhibits better optical properties than that with electron donated alkoxy group because of larger π electron delocalization and dipolar effect. The strong interaction between stilbene pendants and the polyene main chain significantly results in red‐shift of fluorescence emitting peak. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 4529–4541, 2008

The preparation and optical limiting properties of POSS-based molecular hybrid functional materials

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Fluorene‐based click polymers: Relationship between molecular structure and nonlinear optical properties

“…. We can see that the nonlinear susceptibilities of these polymers are as high as 10 −10 esu, which are as much as those of nitrogen‐containing polymers . The large nonlinearity may be mainly originated from the high‐electron delocalization between the rigid structure of the fluorene ring and the imine nitrogen of triazole ring.…”

“…In the past years, our group also mainly focused on molecular design and relationship between the molecular structures and their properties of functional PA with large NLO susceptivity . A series of PAs containing azobenzene or stilbene derivatives were designed, and the effects of different pendant structures such as different conjugation length, conjugation bridge structure, and jointed group structure on their optical properties were investigated.…”

Synthesis, spectroscopic and computational characterization of the tautomerism of pyrazoline derivatives from chalcones

“…In order to synthesize O-alkylated chalcone derivatives 1-17, 4-hydroxybenzaldehyde was initially alkylated (79-99% yield), using a Williamson ether synthesis [38][39][40] …”