Evaluation of temperature impact during extrusion on the mixing levels of PS/PA6 by optical monitoring

This work uses on-line monitoring of turbidity to ascertain the temperature impact on the mixing performance of kneading blocks with different geometries. For this purpose, one of the barrel segments of the extruder was modified to incorporate four sampling devices and a slit die containing optical windows. The experiments consisted in reaching steady extrusion and then adding a small amount of tracer. Upon opening each sampling device, material was laterally detoured from the local screw channel and its turbidity were measured by the optical detector. Residence time distribution (RTD) curves were obtained at various axial positions along three different kneading blocks and under different temperatures. It is hypothesized that K, a parameter related to the area under each RTD curve, is a good indicator of dispersive mixing, whereas variance can be used to assess distributive mixing. The experimental data confirmed that these mixing indices are sensitive to changes in processing conditions and that they translate the expected behavior of each kneading block geometry.

• Autores: O. C. Bernardo, Felipe; Canevarolo, Sebastião V.; C. G. Covas, José A.
• Tipo de recurso: Conferencia (Ponencia)
• Fecha de publicación: 2024
• Institución: Universidad de los Andes
• Repositorio: Séneca: repositorio Uniandes
• Idioma: eng
• OAI Identifier: oai:repositorio.uniandes.edu.co:1992/76044
• Acceso en línea: https://hdl.handle.net/1992/76044; https://doi.org/10.51573/Andes.PPS39.GS.EX.2; https://repositorio.uniandes.edu.co/
• Palabra clave: Mixing; Optical Properties; Temperature; Twin-Screw Extrusion; RTD Curves; Ingeniería
• Rights: openAccess
• License: https://repositorio.uniandes.edu.co/static/pdf/aceptacion_uso_es.pdf