Tecnologia em Metalurgia, Materiais e Mineração
https://tecnologiammm.com.br/article/doi/10.4322/2176-1523.1139
Tecnologia em Metalurgia, Materiais e Mineração
Artigo Original

MÉTODO SIMPLES PARA DETERMINAR DISTRIBUIÇÃO DE TEMPO DE RESIDÊNCIA DE POLÍMEROS EM EXTRUSORA A PARTIR DE MEDIDAS DE LUMINÂNCIA

SIMPLE METHOD FOR DETERMINATION OF THE RESIDENCE TIME DISTRIBUTION OF POLYMERS IN EXTRUDER FROM LUMINANCE MEASUREMENTS

Silva, Daniel José da; Yoshida, Satoru; Takimoto, Herick Garcia; Bizzo, Maurizio André; Kimura, Vanessa Tiemi; Santos, Emerson Roberto dos; Wang, Shu Hui

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Resumo

A distribuição de tempo de residência (RTD) é uma ferramenta poderosa que pode ser usada para a análise das condições do processo de extrusão. Quando se trata de polímeros, a qualidade do produto acabado é fortemente afetada pelos parâmetros de processamento a que estes materiais são submetidos. Desta forma, a RTD tem sido amplamente empregada para avaliar a extrusão destes materiais. Neste trabalho foi determinada a RTD do polipropileno processado em extrusora monorrosca e, além disso, foi avaliada a influência da velocidade de rotação da rosca sobre o tempo médio de residência e a capacidade de mistura da extrusora. Nas condições de processamento utilizadas, os resultados mostraram que o aumento da rotação reduz o tempo de residência e, ao mesmo tempo, favorece uma melhor homogeneização do fundido.

Palavras-chave

Extrusão, Distribuição de tempo de residência, Luminância, Polímeros.

Abstract

The residence time distribution (RTD) is a powerful tool and it can be used to analyze the conditions of the extrusion process. For polymers, the quality of the products is strongly affected by the processing parameters that are applied to such materials. Thus RTD has been widely used to evaluate their extrusion. In this work, RTD of polypropylene extrusion in a single screw extruder was determined and the influence of the rotation speed of the screw on the mean residence time and the mixing ability of the extruder were evaluated. Under the range of the extrusion conditions, the results have shown that the increment of the rotation speed reduces the residence time and, at the same time, enhances the homogeneity of the melt.

Keywords

Extrusion, Residence time distribution, Luminance, Polymers.

Referências

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