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ABSTRACT A water-soluble rigid-rod polyelectrolyte sPBI-PS(Li+) could be doped with LiI and cast as a freestanding film from aqueous solution showing a room-temperature in-plane DC conductivity (s|| ) of 8.3¢®10-3 S/cm. However, the cast film assumed an anisotropic microstructure due to preferential orientation of the rigid-rod backbone leading to an out-of-the plane DC conductivity (s^) which was three orders smaller than those of the s||, and severely limited its applications as a solid polyelectrolyte for thin-film battery. In addition to synthesizing rigid-rod polyelectrolyte sPBI-PS(Li+) for comparison, this study used 2-sulfo-terephthalic acid and isophthalic acid in ratios of 15¡G1, 25¡G1, or 50¡G1 for copolycondensation reaction making the rigid-rod backbone of sPBI-PS(Li+) become articulated. Further reaction with 1,3-propanesultone pendants, the rigid-rod polyelectrolyte was changed into a new water-soluble articulated rigid-rod polyelectrolyte A-sPBI-PS(Li+). Various analyses were applied to ascertain chemical structure, purities, thermal properties and molecular weight of synthesized monomers and polymers. Freestanding films of sPBI-PS(Li+) and A-sPBI-PS(Li+) were cast from aqueous solutions doped with LiI, LiBF4, or LiCF3SO3 for various concentrations up to 5 wt.%. Thin-film room-temperature s|| of sPBI-PS(Li+) could be 3.15´10-3 S/cm, and of A-sPBI-PS(Li+) could be 2.76´10-3 S/cm. X-ray scattering and electron microscopic results suggested that the sPBI-PS(Li+) cast film was in-plane isotropic but out-of-the plane anisotropic, and the A-sPBI-PS(Li+) cast film was three-dimensionally isotropic.

A water-soluble rigid-rod polyelectrolyte sPBI-PS(Li+) could be doped with LiI and cast as a freestanding film from aqueous solution showing a room-temperature in-plane DC conductivity (

ABSTRACT sPBI is a heterocyclic aromatic polymer assuming a para- catenated backbone yielding a rod-like configuration. Because of its rigidity, this rod-like molecule displays superior mechanical tenacity, thermo-oxidative stability, and solvent resistance. It is also the precursor of rigid-rod solid polyelectrolyte exhibiting high solubility and superior ionic conductivity. Isotropic solution were prepared by dissolving sPBI in distilled methanesulfonic acid containing 0.0, 0.989, 4.76, 9.09, 15.0, 20.0, 23.1 wt. % lithium ion of dopants of LiCF3SO3 or LiN(CF3SO2)2. The room-temperature DC conductivity of sPBI cast film doped with 15.0 wt. % LiN(CF3SO2)2 parallel (

Esta dissertação apresenta a caracterização e o preparo de filmes a partir de amido de mandioca nativo e modificado industrialmente (amido acetilado e amido oxidado - acetilado), através da plastificação com glicerol , sorbitol ou etileno glicol. Estes filmes foram preparados adicionando-se um sal (perclorato de lítio) com o propósito de serem utilizados como eletrólitos sólidos poliméricos (ESP), os quais apresentam grande potencial de aplicação em dispositivos eletrocrômicos, sensores e baterias, por isso os ESPs devem ser: transparentes, apresentar boa aderência e maleabilidade além de boa condutividade iônica. As modificações conferidas ao amido foram estudadas empregando-se técnicas caracterização por espectroscopia no infravermelho, RMN e análise elementar. A distribuição de massa molecular das amostras de amido nativo e dos amidos modificados também foi estudada através da técnica de cromatografia de permeação em gel (GPC). Os filmes foram preparados utilizando-se diferentes proporções de plastificante e de sal e em seguida com intuito de efetuar as caracterizações físico-químicas estas amostras foram submetidas à análises de espectroscopia de impedância eletroquímica, difração de Raios-X, Microscopia Eletrônica de Varredura (MEV), análises espectrofotométricas de UV-visível, além das análises térmicas (TG e DSC). / This dissertation presents the preparation and characterization of films obtained from native and industrially modified (acetilate and oxidate-acetilate), cassava starches, through the plasticization with glycerol, sorbitol or ethylene glycol. These films are prepared adding a salt (lithium perchlorate) so that they can be used as solid polymeric electrolytes (ESP), which present great application potential in electrochromic devices, sensors and batteries, therefore the films obtained must be transparent, present good adherence and flexibility besides good ionic conductivity. The modifications of the starch were studied using techniques of characterization by infrared espectroscopy, RMN and elementary analysis. The distribution of the molecular mass of the samples of native and modified starches was also studied by means of gel permeation chromatography (GPC). The films were prepared using different proportions of plasticizers and salt. For the physical-chemical characterization of the samples, they were subjected to analyses of electrochemical impedance spectroscopy, X-Ray diffraction, Scanning Electronic Microscopy (SEM), Uv-visible spectroscopy, besides thermal analyses (TG and DSC).

Articulated rigid-rod polymers asPBI were synthesized via polycondensation reaction. Using 2-sulfoterephthalic acid and 5-sulfoisophthalic acid in different ratios for copolycondensation reaction making the fully conjugated rigid-rod backbone became articulated. Both rigid-rod and articulated rigid-rod were further derivatized using alkane sulfonated pendants and became water-soluble rigid-rod and articulated rigid-rod polyelectrolytes. Lithium salt doped cast films of the polyelectrolytes showed a root-temperature DC conductivity parallel to film surface (

This study utilized polycondensation reaction to synthesize fully conjugated rod-like polymer dihydroxy-PBI. Chemical derivatizations were applied to attach pendants of propane sulfonic coil for dihydroxy-PBI-PS and to attach aromatic phenylene ring with Li ionic moiety for dihydroxy-PBI-AS. The attachment of pendants for dihydroxy-PBI-PS was 42.27 % and for dihydroxy-PBI-AS was only for 0.04 % causing by stereo hindrance of this molecule. These polymers seemed to have good thermal stability. Dihydroxy-PBI started to show degradation at 467.8 oC and retained 60.5 wt. % at 800 oC. Derivatized dihydroxy- PBI-PS and dihydroxy-PBI-AS lost their pendants at 295.3 oC and 314.4 oC, respectively. Dihydroxy-PBI was cast into thin film. Upon doping with lithium salt of LiClO at 2.02 wt. %, dihydroxy-PBI cast film showed the highest room-temperature dc conductivity parallel to the film (£m¡ü) of 1.71 x 10-4 S/cm and perpendicular to the film (£m¡æ) of 1.49 x 10-5 S/cm. For dihydroxy-PBI-PS cast film, the highest conductivity was at 0.49 wt. % of LiClO4 with £m¡ü of 1.05 x 10-3 S/cm and £m¡æ of 1.05 x 10-4 S/cm. For dihydroxy-PBI-AS cast film, the highest conductivity was at 2.02 wt. % of LiClO4 with £m¡ü of 1.32 x 10-3 S/cm and £m¡æ of 2.26 x 10-5 S/cm. From scanning electron microscopy and wide-angle x-ray scattering, it was learned that cast films of dihydroxy-PBI and dihydroxy-PBI-AS had anisotropic layered structure parallel to the film, and that of dihydroxy-PBI-PS showed less of this anisotropy.

Die Systeme CuBiQX (Q = S, Se; X = Cl, Br, I) konnten um zahlreiche Verbindungen erweitert werden. Den meisten dieser Materialien ist ein rigides Netzwerk der Anionenpolyeder um die Bismutkationen gemein. Der Majorität der Verbindungen ist außerdem zumindest eine lokale Beweglichkeit der Kupfer(I)-Ionen immanent. Diese konnte sowohl mittels isotroper Verfeinerungen als auch durch harmonisch und anharmonisch verfeinerte und mittels JPDF zusammengefasste Elektronendichten nachgewiesen werden. Hieraus waren Berechnungen der Potentiale, der Potentialbarrieren und deren Fehler möglich.