Mechanical and thermal properties of non-structural adhesive mortar using linear low-density polyethylene (LLDPE) aggregate substitution with vinyl acetate/ethylene (VAE) interface

Linear low-density polyethylene (LLDPE) is a type of plastic with a high percentage of solid waste and is hardly degradable. The characteristics of LLDPE such as high toughness and low density have the potential to be an alternative aggregate substitute for applications in non-structural mortar composites. The purpose of this study was to determine the suitable formulation of LLDPE aggregate substitution against silica sand for the application of non-structural adhesive mortar composites. Vinyl acetate/ethylene (VAE) surfactant (1.2 wt%) was used to improve the interface between LLDPE and the cement matrix. Mechanical testing; XRD and FTIR characterization; density measurements; compression, adhesion, and thermogravimetric test; and morphological observation were carried out in this experiment. The results showed that LLDPE substitution decreased physical properties and accelerated thermal degradation. Cracks occurred on higher amount of LLDPE composition due to big difference in polarity. Suitable LLDPE substitution composition for adhesive mortar is up to 50%.