Investigation of Rheological and Mechanical Properties of Polypropylene During Recycling Processes

Abstract

In this study, the changes in the molecular structure, rheological and mechanical properties of polypropylene (PP), which is the most widely used industrial polymer, were investigated quantitatively during the recycling processes. In order to represent the recycling process, neat PP-homopolymer was subjected to recycling by extrusion and granulation process for five times, and rheological properties, molecular weights and molecular weight distribution of the samples obtained after each step were examined by a rotational rheometer, and then the tensile test results of the samples prepared in the film forms were evaluated. It was observed that the molecular weight decrease in the recycling processes was mainly occurred in the first recycling process and the decrease continued in each recycling process. It has also been determined that the mechanical strength of the samples below a certain molecular weight causes deterioration in a way that does not even allow forming of film samples.

Keywords

• Polypropylene
• Recycling
• Extrusion
• Rheology
• Mechanical properties
• Mechanical properties.

References

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