A new synthetic strategy was developed to prepare polyphosphazenes with second-order nonlinear optical chromophore in which sulfonyl groups are the acceptors. Thus, polyphosphazenes P1 and P2 that contain aniline or indole groups as side chains were obtained from a highly reactive macromolecular intermediate, poly(dichlorophosphazene), by nucleophilic substitution reaction. Then a post-azo coupling of p-ethylsulfonylbenzenediazonium fluoroborate or p-octylsulfonylbenzenediazonium fluoroborate toward the aniline or indole ring in P1 and P2 afforded the sulfonyl-based hromophorefunctionalized polyphosphazenes P3, P4, and P5. The polymers exhibit good solubility in common organic solvents and are thermally stable. The maximum absorption appeared at about 440nm in P3, while that of P4 was at about 393nm, which were blue-shifted about 52 and 32nm, respectively, compared to the corresponding chromophores with nitro acceptor and resulted in a wider transparency window. The poled films of P3 and P4 exhibits a resonant d33 value of 27 and 18pm/V, respectively, by second harmonic generation (SHG) measurements.

The synthesis and structural characterization of a series of novel, fluorinated poly(phthalazinone ether)s containing perfluorophenylene moieties are described. The monomers, 4-(4-hydroxyaryl)phthalazin-1(2H)-ones (2a-2d), were conveniently and efficiently synt esized from phenols and phthalic anhydride in two steps via 2-(4-hydroxybenzoyl)benzoic acids, which were first obtained by the Friedel-Crafts reaction in good yields and with high stereoselectivity and were then converted into 2a-2d by fusion with hydrazine. All the polymers were prepared by nucleophilic aromatic substitution (SNAr) polycondensation between the compounds perfluorobiphenyl and 4-(4 -hydroxyaryl)phthalazin-1(2H)-ones (2a-2d). The resulting fluorinated polymers were readily soluble in common organic solvents (e.g., CHCl3, tetrahydrofuran, dimethylformamide, dimethyl sulfoxide, N-methylpyrrolidone, etc.) at room temperature. Their weight-average molecular weights and the polydispersities ranged from (7.96-18.25)×103 to 1.31-2.71, respectively. Their glass-transition temperatures varied from 213 to 263℃. They were all stable up to 390℃ both in air and in argon. The 5% weight-loss temperatures of these polymers in air and argon ranged from 393-487 to 437-509℃, respectively. Wide-angle X-ray diffraction studies indicated they were all amorphous and could be attributed to the presence of kink nonplanar moiety, phenyl phthalazinone along the polymer backbone.

)mc, with a=7.7281(14) Å, b=7.7281(14) Å, c=6.742(2) Å,α=90°, β=90°, γ=120°, Z=2. It was obtained by a new preparation procedure different from that reported in the literature that gave a centrosymmetric structure. The structure contains Cd-Br octahedrons, which are connected in a plane-sharing way to form edimensional long chains. Each octahedron is slightly distorted, as the three Cd-Br bond lengths are 2.774 Å, while the other three Cd-Br bond lengths are 2.804 Å. The distortion directions of all of the octahedrons are almost parallel and give rise to the accumulation of the microcosmic nonlinear optical (NLO) coefficient. The Kurtz powder technique shows that CsCdBr3 has a powder second harmonic generation of about 2 times as large as that of potassium dihydrogen phosphate (KDP). It shows excellent ransparency in the visible and infrared regions. The thermal stability is also good. Therefore it may be utilized as a potential nonlinear optical crystal for the IR region.

A new strategy for postfunctionalization performed on poly(N-vinylcarbazole) (PVK) has been explored to develop PVK-based nonlinear optical (NLO) polymers with a high density of chromophores and improved comprehensive properties. Thus, under the standard Vilsmeier reaction conditions, PVK is partially formylated to a high degree (up to 52% molar ratio), and these formyl groups of high reactivity are condensed with cyanoacetylated DR-1 to afford a DR-1 functionalized PVK in almost complete conversion. The Tg of the resulting polymer is 185℃, and the orientation behavior of its poled film is studied by UV-visible spectroscopy. The NLO activity, which is estimated to be 20pm/V by in situ second harmonic generation measurement, remains unchanged at 120℃ for over 1000h after a minor initial drop.