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Preparation of fluorescent hyperbranched polymer materials by end-capping approach
Chao Gao,Deyue Yan
Chinese Science Bulletin , 2000, DOI: 10.1007/BF02886261
Abstract: Two kinds of novel fluorescent hyperbranched polymers were synthesized by the end-capping approach. The fluorescent hyperbranched polyether (FPEOTM) was obtained by end capping the hyperbranched poly(hydroxyl ether) (PEOTM) with guest molecules N,N-dimethylaminobenzaldehyde (DMABA). In addition, in the presence of triethylamine, the hyperbranched polysulfone-amine with terminal double bonds (HPSA) was synthesized by polyaddition of a new AB2 type monomer (SAP, sulfone amine piperazine) at 40°C for 60 h in chloroform solution. Then the fluorescent hyperbranched polysulfone-amine (FHPSA) was prepared by addition of guest molecules N, N-dimethylaminoanilines (DMAA) with the terminal double bonds of HPSA. The two resulting polymers fluoresce yellow-green color in both solid and solution states. The maximum emission wavelength is (460±10) nm and (470±10) nm, respectively. A novel “complex quenching effect” for hyperbranched polymer was observed. The fluorescence can be quenched by transition metal cations such as Ag+, cu2+ and Fe3+, while alkali and alkaline earth metal cations almost have no influence on the fluorescence intensity.
Research on All Optical Poling for the Organic Polymer PMMA Film Doped with Disperse Orange 25

Fan Xizhi,

光子学报 , 2005,
Abstract: Using disperse orange 25 as guest dye, the doped film sample of organic polymer PMMA was fabricated and all optical poled. The stronger the intensity of the two writing light beams correspond to the faster the second order susceptibility for the second nonlinear optical effect by the all optical poling achieves the saturation. The quality of the second nonlinear optical effect in the film was affected by several factors such as the difference between phases, the ratio of intensities of light beams, the ratio of intensity of optical fields of two writing beams.
Short hybrid polymer/sol-gel silica waveguide switches with high in-device electro-optic coefficient based on photostable chromophore
Y. Enami,J. Luo,A. K-Y. Jen
AIP Advances , 2011, DOI: 10.1063/1.3662038
Abstract: The highest electro-optic (EO) coefficient to date is achieved in short polymeric directional coupler switches based on hybrid EO polymer/sol-gel silica waveguides. Optimized poling conditions in such waveguides give a highest in-device EO coefficient of 160 pm/V at 1550 nm using highly efficient and photostable guest–host EO polymer SEO100. Adiabatic waveguide transitions from the passive sol-gel core to active EO polymer cores surrounding the sol-gel core are shown using EO polymer cores with a coplanar tapered structure. Switching voltages of 8.4 and 10.5 V are achieved for electrodes that are 2.1 and 1.5 mm long, respectively, which are half those of EO switches containing the chromophore AJLS102.
Nonlinear optical polyimide with high thermal stability prepared by simultaneous poling and polymerization
Hu Kang,Wei Wu,Peiji Wu,Cheng Ye
Chinese Science Bulletin , 2001, DOI: 10.1007/BF02900432
Abstract: The highT g polyimide embedded with a novel imidazol-typed chromophore 2-[5-(4-nitrostilbenyl)thienyl]-4,5-di(4-aminophenyl)imidazole (NSTDAPI) was prepared using the “simultaneous poling and polymerization” technique. The glass transition temperature (T g ) is 304° C and the initial decomposition temperature (T d ) is 330° C. Thein-situ second harmonic generation (in-situ SHG) measurement was performed to study its poling behavior and the stability of the poling-induced orientation. The nonlinear optical (NLO) coefficientd 33 of poled polyimide film is 32.2 pm/V at 1064 nm fundamental wavelength. The SHG signal of the poled polymer film was quite stable below 200°C, and then began to decay rapidly above 220° C. The half-decay temperature of dipole orientation for the film is 250° C.
A Pyrene- and Phosphonate-Containing Fluorescent Probe as Guest Molecule in a Host Polymer Matrix  [PDF]
Elise Villemin,Benjamin Elias,Michel Devillers,Jacqueline Marchand-Brynaert
Molecules , 2013, DOI: 10.3390/molecules18021897
Abstract: New host-guest materials have been prepared by incorporation of a home-made organic probe displaying a pyrene motif and a phosphonate function into a regular amphiphilic copolymer. Using powder X-Ray diffraction, photoluminescence and FT-IR spectroscopy, we have been able to study the non-covalent interactions between the host matrix and the guest molecule in the solid state. Interestingly, we have shown that the matrix directs the guest spatial localization and alters its properties. Thanks to the comparison of pyrene vs. N-pyrenylmaleimide derivatives, the influence of the chemical nature of the guest molecules on the non-covalent interactions with the host have been studied. In addition, using polyethylene glycol as a reference host, we have been able to evidence a true matrix effect within our new insertion materials. The phosphonated guest molecule appears to be a novel probe targeting the hydrophilic domain of the host copolymer.

,刘丽英,杨 鹏,侯占佳,徐 雷,王文澄

物理学报 , 1999,
Abstract: Sol-gel method was used to prepare SiO2-GeO2 films. By investigating the second-harmonic generation signal of the film after parallel plate poling and corona poling, it was found that the number of effective dipoles in the sample increased with the plate poling voltage. A model of the release of effective dipoles was proposed to explain the super-quadratic relation between the second-order nonlinearity and the poling voltage.
Second harmonic generation with DSR1-PMMA polymer films  [cached]
H. Tajalli,E. Mohajerani,S. Ahmadi,R. Kheradmand
Iranian Journal of Physics Research , 2000,
Abstract: The poling process of polymers doped with chromophores is of great importance for the nonlinear properties of these materials. So, after having optimized the poling condition the second harmonic generation (SHG) was measured for PMMA polymer doped with Disperse Red 1. The dependence of SHG intensity to the poling voltage and poling temperature have been experimentally studied. The relaxation of dopant orientation in the polymer matrix was also measured.
Simulations on the electromechanical poling of ferroelectric ceramics  [PDF]
Yin-Zhong Wu,Yong-Mei Tao
Physics , 2007, DOI: 10.1063/1.2817624
Abstract: Based on the two-step-switching model, the process of electromechanical poling of a ferroelectric ceramics is simulated. A difference of the remnant polarizations between two poling protocols (mechanical stress is applied before and after the application of poling field) is found from our simulations, which is also observed in experiment. An explanation is given to illustrate why the remnant polarization for the case that mechanical stress is loaded after the application of electric field is larger than the case that mechanical stress is loaded before the application of electric field. Our simulation results supply a proof for the validity of the two-step-switching model in the electromechanical poling of polycrystalline ferroelectric ceramics.
Investigation of Bioglass-Electrode Interfaces after Thermal Poling  [PDF]
C. R. Mariappan,B. Roling
Physics , 2007,
Abstract: Electrical and electrochemical processes in a bioactive soda-lime phosphosilicate glasses and in a bioabsorbable soda-lime phosphate glass during thermal poling were studied by means of thermally stimulated depolarization current measurements, ac impedance spectroscopy, and SEM/EDX analyses. The thermal poling was done by sputtering thin Pt electrode films onto the faces of the glass samples and by applying voltages up to 1 kV to the electrodes at temperatures up to 513 K. The poling leads to the formation of interfacial layers under the electrodes which are responsible for two depolarization current peaks and for one additional semicircle in a Nyquist plot of the ac impedance. The SEM/EDX profiles suggest that redox and transport processes of Na+ ions are responsible for the formation of the interfacial layers and that Ca2+ ions are immobile under the poling conditions. The sodium depletion layer under the anode leads to a negative surface charge of the glass samples which may enhance their bioactivity.
A Facile Strategy for In Situ Core-Template-Functionalizing Siliceous Hollow Nanospheres for Guest Species Entrapment  [cached]
Wang Jun,Gao Xin,Yang Xianyan,Gan Yilai
Nanoscale Research Letters , 2009,
Abstract: The shell wall-functionalized siliceous hollow nanospheres (SHNs) with functional molecules represent an important class of nanocarriers for a rich range of potential applications. Herein, a self-templated approach has been developed for the synthesis of in situ functionalized SHNs, in which the biocompatible long-chain polycarboxylates (i.e., polyacrylate, polyaspartate, gelatin) provide the framework for silica precursor deposition by simply controlling chain conformation with divalent metal ions (i.e., Ca2+, Sr2+), without the intervention of any external templates. Metal ions play crucial roles in the formation of organic vesicle templates by modulating the long chains of polymers and preventing them from separation by washing process. We also show that, by in situ functionalizing the shell wall of SHNs, it is capable of entrapping nearly an eightfold quantity of vitamin Bc in comparison to the bare bulk silica nanospheres. These results confirm the feasibility of guest species entrapment in the functionalized shell wall, and SHNs are effective carriers of guest (bio-)molecules potentially for a variety of biomedical applications. By rationally choosing the functional (self-templating) molecules, this concept may represent a general strategy for the production of functionalized silica hollow structures.
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