| Name: | Description: | Size: | Format: | |
|---|---|---|---|---|
| 7.87 MB | Adobe PDF |
Advisor(s)
Abstract(s)
A presente dissertação tem como objetivo a melhoria dos métodos de análise utilizados na empresa, considerando: o poder dispersante de produtos auxiliares em corantes reativos, o poder dispersante de produtos auxiliares em corantes dispersos, o poder de molhagem de um tecido, o poder sequestrante de cálcio do produto auxiliar a testar e o poder sequestrante de ferro do produto auxiliar a testar. O poder dispersante corresponde ao poder de um certo produto dispersar o corante pela fibra e o poder sequestrante, representa o poder de um produto complexar o ião, neste caso, o ião cálcio e o ião ferro. Para o poder dispersante de corantes reativos, o principal obstáculo era o facto de os resultados não serem reprodutíveis nem repetíveis. Sendo assim, foram efetuadas várias hipóteses para melhorar este método sendo que, o método definido final consiste na utilização de corante à temperatura ambiente e papel de filtro do tipo C. Para o poder dispersante de corantes dispersos, o problema era o mesmo dos corantes reativos. Após várias tentativas para melhorar este procedimento, a escolhida foi a que utiliza 0,2 g/L de corante escarlate itosperse SLK e 2 g/L de produto dispersante como produto auxiliar. No poder de molhagem, ao realizar-se o método inicial do poder de molhagem, o tempo de espera máximo de 5 minutos era ultrapassado bastantes vezes e, por esse motivo, foi necessária a implementação de outro método. Este método foi definido como método da hidrofilidade, em que se coloca o tecido teste numa solução de corante Azul Turquesa Itosperse S-GL 200%, e se mede a distância percorrida pelo corante durante 10 segundos. A avaliação do poder sequestrante de cálcio é efetuada pela reação entre o carbonato de sódio com o acetato de cálcio que torna a solução turva, tendo em conta que o volume gasto de acetato de cálcio é considerado para o cálculo do poder sequestrante. A principal dificuldade é a visualização do ponto de turbidez para soluções transparentes, sendo que a solução encontrada foi adicionar corante Amarelo Lx (1:1000). Por fim, para o poder sequestrante de ferro, o método era realizado num laboratório externo à empresa (Laboratório do CIETI/ISEP), porém, os resultados obtidos eram bastante semelhantes quando se avaliavam produtos auxiliares diferentes. Para resolução deste problema, foram desenvolvidos dois métodos que, atuando em simultâneo, fornecem resultados fidedignos. Estes métodos consistem em utilizar a máquina de tingimento, realizando uma filtração a vácuo dos tubos de tingimento e por fim, utilizar o espectrofotómetro para determinar a absorvância de cada produto, calculando a respetiva atividade quelante.
This dissertation aims to improve the analysis methods used in the company, considering: the dispersing power of auxiliaries in reactive dyes, the dispersing power of auxiliaries in dispersed dyes, the wetting power of a fabric, the calcium sequestering power of the auxiliary product to be tested and the iron sequestering power of the auxiliary product to be tested. The dispersing power corresponds to the power of a certain product to disperse the dye through the fiber and the sequestering power, represents the power of a product to complex the ion, in this case, the calcium ion and the iron ion. For the dispersing power of reactive dyes, the main obstacle was that the results were not reproducible or repeatable. Therefore, several hypotheses were made to improve this method, and the final defined method is the use of cold dye and C filter paper. For the dispersing power of disperse dyes, the problem was the same as for reactive dyes. After several attempts to improve this procedure, the one chosen was the one using 0.2 g/L itosperse SLK scarlet dye and 2 g/L dispersant as an auxiliary product. In the wetting power, when performing the initial wetting power method, the maximum waiting time of 5 minutes was exceeded several times, and for that reason, another method had to be implemented. This method was defined as the hydrophilicity method, in which the test tissue is placed in a solution of Itosperse S-GL Turquoise Blue 200% dye, and the distance traveled by the dye in 10 seconds is measured. The evaluation of the calcium sequestering power is performed by the reaction between sodium carbonate and calcium acetate that makes the solution turbid, considering that the spent volume of calcium acetate is considered for the calculation of the sequestering power. The main difficulty is the visualization of the turbidity point for transparent solutions, and the solution found was to add dye Yellow Lx (1:1000). Finally, for the iron sequestering power, the method was performed in a laboratory outside the company (CIETI/ISEP Laboratory), but the results obtained were quite similar when different auxiliary products were evaluated. Two methods were developed that, acting simultaneously, provide reliable results. These methods consist in using the dyeing machine, performing a vacuum filtration of the dyeing tubes and finally using the spectrophotometer to determine the absorbance of each product, calculating the respective chelating activity.
This dissertation aims to improve the analysis methods used in the company, considering: the dispersing power of auxiliaries in reactive dyes, the dispersing power of auxiliaries in dispersed dyes, the wetting power of a fabric, the calcium sequestering power of the auxiliary product to be tested and the iron sequestering power of the auxiliary product to be tested. The dispersing power corresponds to the power of a certain product to disperse the dye through the fiber and the sequestering power, represents the power of a product to complex the ion, in this case, the calcium ion and the iron ion. For the dispersing power of reactive dyes, the main obstacle was that the results were not reproducible or repeatable. Therefore, several hypotheses were made to improve this method, and the final defined method is the use of cold dye and C filter paper. For the dispersing power of disperse dyes, the problem was the same as for reactive dyes. After several attempts to improve this procedure, the one chosen was the one using 0.2 g/L itosperse SLK scarlet dye and 2 g/L dispersant as an auxiliary product. In the wetting power, when performing the initial wetting power method, the maximum waiting time of 5 minutes was exceeded several times, and for that reason, another method had to be implemented. This method was defined as the hydrophilicity method, in which the test tissue is placed in a solution of Itosperse S-GL Turquoise Blue 200% dye, and the distance traveled by the dye in 10 seconds is measured. The evaluation of the calcium sequestering power is performed by the reaction between sodium carbonate and calcium acetate that makes the solution turbid, considering that the spent volume of calcium acetate is considered for the calculation of the sequestering power. The main difficulty is the visualization of the turbidity point for transparent solutions, and the solution found was to add dye Yellow Lx (1:1000). Finally, for the iron sequestering power, the method was performed in a laboratory outside the company (CIETI/ISEP Laboratory), but the results obtained were quite similar when different auxiliary products were evaluated. Two methods were developed that, acting simultaneously, provide reliable results. These methods consist in using the dyeing machine, performing a vacuum filtration of the dyeing tubes and finally using the spectrophotometer to determine the absorbance of each product, calculating the respective chelating activity.
Description
Keywords
Branqueio Tingimento Corantes dispersos Corantes reativos Molhagem Cálcio Ferro Papel de filtro Bleaching Dyeing Disperse dyes Reactive dyes Wetting Calcium Iron Filter paper