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Síntese e caracterização de monômeros azo-carbonatos para a preparação de poli(azo-carbonato)s e poli)azo-uretana)s

Authors: Capitão, Rebeca Monique;

Síntese e caracterização de monômeros azo-carbonatos para a preparação de poli(azo-carbonato)s e poli)azo-uretana)s

Abstract

Os axo-compostos aromáticos apresentam uma versatilidade de aplicações em diversas áreas, como têxtil, farmacêutica, cosmética, alimentar, tecnológica (como lasers, displays de cristal líquido e dispositivos eletro-ópticos) e em síntese orgânica. A primeira parte deste trabalho descreve a síntese de compostos do tipo azo-diol. Esses compostos foram caracterizados por técnicas espectroscópicas (RMN, FT-IR, UV-vis) e espectrométrica (ESI-MS). Além disso foram realizar cálculos teóricos para determinar a influência do grupo p-substituinte no comprimento de onda de absorção máxima dos espectros de absorção no UV-vis. Na sequência, discute-se a preparação de monômeros azo-carbonatos por duas rotas sintéticas. Uma pela reação direta do azo-diol com DMC e a outra por meio de acoplamento de sais de arildiazônio com bis-carbonato. Por fim, testou-se a reatividade dos monômeros azo-carbonatos em reações de policondensação com um diol o uma diamina utilizando TBD como catalisador para formação de poli(azo-carbonato) ou poli(azo-uretana), respectivamente. O catalisador TBD mostrou-se eficiente para a reação de policondensação e as estruturas dos copolímeros foram confirmadas por técnicas espectroscópicas (RMN, FT-IR, UV-Vis) e espectrométrica (MALDI-TOF), onde pode-se determinar os diferentes grupos terminais das cadeias poliméricas formados

Aromatic azo-compounds have a wide range of applications, such as textile, pharmaceutical, cosmetics, food, technology (as lasers, liquid crystal displays and electro-optical devices) and advanced organic synthesis. The first part of this work describes the synthesis of azo-dialcohol compounds in good yields. These compounds were chareacterized by NMR, IR and UV-VIS spectroscopy and by mass spectrometry with electrospray ionization (ESI-MS). Moreover, theoretical calculation were performed to determine the influence of the psubstituent group at the wavelength of maximum absorption of the spectra of UV-vis. Following, we discuss the preparation of azo-carbonates monomers by two synthetic routes. One way by direct reaction of the diol and DMC and another by coupling of aryldiazonium salts with bis-carbonate. Finally, we tested the reactivity of azo-carbonate monomers in the polycondensation reaction with a diol or a diamine using TBD as a catalyst for the formation of poly(azo-carbonate) or poly(azo-urethane), respectively. The TBD catalyst was efficient for the reaction of polycondensation and the structures of the copolymers were confirmed by FT-IR, NMR and MALDI-TOF, allowing determinate the different end-groups of the polymer chains formed

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Pós-graduação em Ciência e Tecnologia de Materiais - FC

Country
Brazil
Keywords

Monomeros, Polímeros, Atomos, Ciência dos materiais, Materials science

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selected citations
These citations are derived from selected sources.
This is an alternative to the "Influence" indicator, which also reflects the overall/total impact of an article in the research community at large, based on the underlying citation network (diachronically).
BIP!Citations provided by BIP!
popularity
This indicator reflects the "current" impact/attention (the "hype") of an article in the research community at large, based on the underlying citation network.
BIP!Popularity provided by BIP!
influence
This indicator reflects the overall/total impact of an article in the research community at large, based on the underlying citation network (diachronically).
BIP!Influence provided by BIP!
impulse
This indicator reflects the initial momentum of an article directly after its publication, based on the underlying citation network.
BIP!Impulse provided by BIP!
0
Average
Average
Average
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