Hybrid Matrix Using Polyester Resin to Improve the Physical and Mechanical Properties of Recycled Expanded Polystyrene Matrix

In this study, an innovative hybrid matrix based on recycled expanded polystyrene (EPS), dissolved in gasoline, and polyester resin (PR) is developed. The aim is to improve the physical and mechanical properties of the dissolved EPS, used previously by the authors as a matrix in composite materials. A rate of 20, 30, 40, 50, and 60 wt% of PR were added in the EPS/PR hybrid matrix. Two processes were used for drying the hybrid matrix, namely ambient temperature (ATDP) and thermal drying process (ThDP) at 60C degrees. Pycnometer and three-point bending measurements with a characterization by scanning electron microscopy (SEM) were carried out in order to determine: the bulk density, the flexural modulus, and the maximum stress and also to observe the EPS/PR morphology. The results showed that the addition of PR increases the physical properties of the EPS/PR hybrid matrix in both drying processes with a drastic improvement of 3 to 6 times in the mechanical properties. Using ThDP at 60 degrees C makes the matrix lighter and more resistant even at 20 wt% of PR than using ATDP. Otherwise, using ThDP can increase the density from 7 to 16% and improve the tensile strength from 11 to 64% of the dissolved EPS. It was concluded that the elaboration of the innovative hybrid matrix EPS/PR with ThDP at 60 degrees C improves the physical and mechanical properties of the EPS. Thus, the authors recommend the use of solar flat plate collectors as a renewable drying process.