Obtaining an Empirical Equation for Correcting the Melt Flow Index of Virgin and Recycled Polypropylene Mixtures and Analysis of Mechanical Properties of the Blends

Abstract

Polypropylene is one of the most used materials in the world because of its easy processability and good mechanical properties under different applications. As a result, a lot of polypropylene waste is being generated and recycling is important. The problem with recycling polypropylene is the changing in the properties when compared to virgin polypropylene. Processability parameters and mechanical properties of traction and impact can be changed after recycling this material, affecting companies in the polymer transformation sector. Thus, this work aims to obtain an empirical equation for the correction of the melt flow index of virgin and recycled polypropylene mixtures and also conducts a study on the mechanical properties of the mixtures comparing them with those of virgin polypropylene. The empirical equation found shows a linear relationship between the melt flow index of the mixture and the percentage amount of virgin polypropylene. From the mechanical properties, it was observed that the stiffness of the mixtures is similar to that of virgin polypropylene, however the energy absorbed under impact is considerably lower, compromising the use of recycled polypropylene for such application.