Produção Nacional
BAMBOO PULP TREATED WITH NaOH AND BENZOPHENONE TETRACARBOXYLIC DIANHYDRIDE AS REINFORCEMENT OF NEW POLYMERICS MATERIALS ( PULPA DE BAMBÚ TRATADA CON NaOH Y DIANHÍDRIDO BENZOFENONA TETRACARBOXÍLICO COMO REFUERZO DE NUEVOS MATERIALES POLIMÉRICOS )
2013; Linguagem: Inglês
ISSN
2244-7113
AutoresMario Guimarães Junior Guimarães, Kátia Monteiro Novack, Vagner Roberto Botaro,
Tópico(s)Natural Fiber Reinforced Composites
ResumoBamboo admittedly and engineering material widely used for buildings in several countries. However, lack of good interfacial adhesion, low melting point, and poor resistance towards moisture make the use of natural fiber reinforced composites less attractive. The aim of this work was esterify the refined pulp of bamboo came from kraft industrial pulping, previously treated with sodium hydroxid and organic solvents for the production of less hydrophilic materials. In order to verify the occurrence of reaction, assays of spectroscopy in the region of IV, thermogravimetry, elementary analysis and water absorption were performed. After the reaction, the infrared spectra presented bands related to the ester and carboxylic acid groups, evidencing the exchange of OH groups for ester groups. This test also shows a decrease in the absorbance ratio due to the presence of ester group causing a reduction in the crystallinity index of the sample. These results were proven by the gain in the value of carbon content after the elementary analysis. In the water absorption test, the pulp modified with dianhydride showed the lowest level as compared to other samples. The thermogravimetric analysis also showed a decrease in initial temperature of pulp degradation, as well as decrease in the moisture, facts that proved the efficiency in the modification using dianhidrido BTDA. El objetivo de este trabajo fue esterificar pulpa refinada procedente de bambu industrial kraft, pre-tratados con hidroxido de sodio y disolventes organicos para producir materiales menos hidrofilicos. Con el fin de verificar la aparicion de reaccion de esterificacion, espectroscopia infrarroja, analisis termogravimetrica, analisis elemental y absorcion de agua fueron realizadas. Despues de la reaccion, el espectro infrarrojo mostro bandas relacionadas con los grupos ester y grupos de acido carboxilico, que muestra el intercambio de grupos OH por grupos ester. Esta pruebla tambien mostro una proporcion reducida de la absorbancia debido a la presencia del grupo ester causando una reduccion en el indice de cristalinidad de la muestra. Estos resultados se corroboraron por un aumento en la cantidad de contenido de carbono despues del analisis elemental. En la prueba de absorcion de agua, la pulpa modificada con dianhidrido mostro el nivel mas bajo en comparacion con otras muestras. El analisis termogravimetrica mostro tambien una reduccion en la temperatura de inicio de la degradacion de pulpa refinada, asi como una disminucion en el contenido de humedad, los eventos que demostraron la eficacia de la modificacion utilizando BTDA dianhidrido.
Referência(s)