Theoretical–experimental study of the action of trace amounts of formaldehyde, propionaldehyde, and butyraldehyde as inhibitors of the ziegler–natta catalyst and the synthesis of an ethylene–propylene copolymer

The copolymer synthesis process can be affected by failures in the production process or by contaminating compounds such as ketones, thiols, and gases, among others. These impurities act as an inhibiting agent of the Ziegler–Natta (ZN) catalyst affecting its productivity and disturbing the polymeriz...

Full description

Autores:
Hernández Fernández, Joaquín
Ortega-Toro, Rodrigo
Castro-Suarez, John R.
Tipo de recurso:
Article of investigation
Fecha de publicación:
2023
Institución:
Corporación Universidad de la Costa
Repositorio:
REDICUC - Repositorio CUC
Idioma:
eng
OAI Identifier:
oai:repositorio.cuc.edu.co:11323/10477
Acceso en línea:
https://hdl.handle.net/11323/10477
https://repositorio.cuc.edu.co/
Palabra clave:
Formaldehyde–propionaldehyde and butyraldehyde
Green ethylene
Ziegler–Natta
Polypropylene
Catalyst
Degradation
Random copolymer
Rights
openAccess
License
Atribución 4.0 Internacional (CC BY 4.0)
Description
Summary:The copolymer synthesis process can be affected by failures in the production process or by contaminating compounds such as ketones, thiols, and gases, among others. These impurities act as an inhibiting agent of the Ziegler–Natta (ZN) catalyst affecting its productivity and disturbing the polymerization reaction. In this work, the effect of formaldehyde, propionaldehyde, and butyraldehyde on the ZN catalyst and the way in which it affects the final properties of the ethylene-propylene copolymer is presented by analyzing 30 samples with different concentrations of the mentioned aldehydes along with three control samples. It was determined that the presence of formaldehyde 26 ppm, propionaldehyde 65.2 ppm, and butyraldehyde 181.2 ppm considerably affect the productivity levels of the ZN catalyst; this effect increases as the concentration of aldehydes is higher in the process; likewise, these impurities affect the properties of the final product, such as the fluidity index (MFI), thermogravimetric analysis (TGA), bending, tension, and impact, which leads to a polymer with low-quality standards and less resistance to breakage. The computational analysis showed that the complexes formed by formaldehyde, propionaldehyde, and butyraldehyde with the active center of the catalyst are more stable than those obtained by the ethylene-Ti and propylene-Ti complexes, presenting values of −40.5, −47.22, −47.5, −5.2 and −1.3 kcal mol−1 respectively