Effects of compatibilizers and electron radiation on thermomechanical properties of composites consisting of five recycled polymers

The purpose of this article is to show the influence of two compatibilizers and an electron radiation dose on the storage modulus (M′), loss modulus (M″), and loss factor (tan δ) of composites made of blends of the following five recycled polymers: low-density polyethylene (LDPE), high-density polyethylene (HDPE), polypropylene (PP), polystyrene (PS), and poly(ethylene terephthalate) (PET). The aim of both adding a compatibilizer and applying high-energy electron radiation, with doses of up to 300 kGy, to the blends was to enhance their mechanical properties and, at the same time, to investigate the possibility of using these procedures for recycling plastic waste. As compatibilizers, styrene-ethylene/butylene-styrene elastomer grafted with maleic anhydride (SEBS-g-MA) and trimethylol propane trimethacrylate (TMPTA) were utilised. They were added in the amounts of 10 and 1 wt%, respectively. It was found that SEBS-g-MA and PS were thermodynamically immiscible with the remaining components of the composites at temperatures ranging from −20 to +150 °C, and that both the addition of TMPTA and the application of the electron radiation insignificantly affected the phase transition temperatures and the loss factor. On the other hand, a significant increase in the tan δ values upon the addition of SEBS-g-MA and/or rise in temperature were observed.