Effects of Different Concentrations of Arsine on the Synthesis and Final Properties of Polypropylene

Abstract

This article studies the effects of arsine on the synthesis and thermal degradation of 4 samples of virgin polypropylene (PP-virgin) and proposes reaction mechanisms that allow understanding of its behaviour. Different points are monitored during the polypropylene synthesis to perform TGA, DSC, FT-IR, RDX, and MFI analyses later. The content of AsH3 in polypropylene varies between 0.05 and 4.73 ppm, and of arsenic in virgin PP residues between 0.001 and 4.32 ppm for PP0 and PP10, increasing in fluidity index from 3.0 to 24.51. The origin of thermo-oxidative degradation is explained by the reaction mechanisms of the Molecule AsH3 with the active titanium center of the ZN catalyst and the subsequent oxidation to form radical complexes. OO-AsH-TiCl4-MgCl2 and (OO-as-OO)2 -TiCl4-MgCl2, which, by radical reactions, give rise to the formation of functional groups aldehyde, ketone, alcohol, carboxylic acid, CO, CO2, PP-Polyol, PP-Polyether, and PP-Isopropylethers. These species caused the TG and DTG curves to increase degradation peaks in pp samples.

Experimental Study of the Impact of Trace Amounts of Acetylene and Methylacetylene on the Synthesis, Mechanical and Thermal Properties of Polypropylene

“…This resin uses propylene as its raw material for its synthesis, which requires a high degree of purity to avoid interference in the process [ 12 , 17 , 18 ]. Studies have shown that the impurities present in the propylene can affect the properties of the synthesized resin, causing the production of resin outside of specifications that becomes waste, generating more pollution, or producing resin that must be processed, generating a high consumption of energy and other raw materials to reach the desired quality [ 19 , 20 ].…”

Iron Oxide Powder as Responsible for the Generation of Industrial Polypropylene Waste and as a Co-Catalyst for the Pyrolysis of Non-Additive Resins

“…The increase in MFI in the samples of polymers synthesized in the presence of external compounds has been evaluated by various authors, where it has been determined that this phenomenon occurs due to the interaction between the ZN catalyst and the different compounds that may be present during polymerization (poisons or external donors), causing a decrease in the molecular weight of the resin obtained [ 25 , 29 , 30 , 31 ], which translates into an increase in the MFI according to the relationship between the average molecular weight and the MFI proposed by Bremner [ 32 , 33 ].…”

“…With the aim of implementing techniques that allow industrially generated waste to be revalued, thermal and catalytic recording have been studied for the generation of excellent quality products that can be marketed [ 20 ]. However, it is necessary to understand how compounds such as iron oxide can affect the production of polypropylene, generating waste as well as how the autocatalytic thermal degradation of these wastes would affect pyrolysis [ 3 , 21 , 22 , 23 , 24 , 25 ]. It is important to evaluate the presence of iron oxide in the synthesis and autocatalysis of polypropylene, since during the preventive and corrective maintenance of petrochemical plants that are dedicated to the synthesis, production, and commercialization of polypropylene, traces of FeO can be released by cleaning the internal walls of the reactors with high-pressure sand and washing with process water that favors the detachment of trace metals from carbon steel.…”

Special Issue: Synthesis, Processing, Structure and Properties of Polymer Materials

“…In this Special Issue, 33 original articles have been published on various topics, including the preparation, characterization, and some examples of application of polymeric materials. This issue includes review articles [ 1 , 2 , 3 , 4 , 5 , 6 , 7 , 8 ] and research articles [ 9 , 10 , 11 , 12 , 13 , 14 , 15 , 16 , 17 , 18 , 19 , 20 , 21 , 22 , 23 , 24 , 25 , 26 , 27 , 28 , 29 , 30 , 31 , 32 , 33 ].…”

“…The scope of research articles of papers included a Special Issue is very wide. It includes papers on the synthesis and study of the properties of new thermoplastic polymers [ 9 , 10 , 11 , 12 , 13 ], obtaining of composites [ 14 , 15 , 16 ], nanocomposites [ 17 , 18 , 19 ], microspheres [ 20 , 21 ], polymeric blends [ 22 , 23 , 24 ], hydrophobic nanostructures [ 25 ], polymeric membranes [ 26 , 27 ], hydrogels [ 28 ] and others [ 29 , 30 , 31 , 32 , 33 ].…”