Compatibilizer effectiveness for the reuse of mixed post-consumer solid waste plastic towards Distributed recycling additive manufacturing

The concept of bypassing the sorting process in post-consumer plastic recycling has emerged as an intriguing solution to circumvent the high costs and inherent inefficiencies of conventional processes. This approach demands the blend of polymers, whose physical properties have been known to be improved with the use of compatibilizers. In this study, the recycled polymer blends based on the two largest-volume waste plastics of poly (ethylene terephthalate) (rPET) and high-density polyethylene (rHDPE) at 90/10 wt% are investigated to develop a method that would be able to recycled water bottles directly. This blend was investigated with and without 10 wt% of three types of styrene-ethylene/butylene (SEBS), two non-reactive compatibilizers named by their code G1650 and G1652 and one maleated SEBS cirKular+ c1010 - (C1010). It was prepared in a co-rotating twin screw extruder and 3-D printed using a large-format fused granular fabrication printer. The results showed that samples manufactured by conventional methods exhibited increases of approximately 50% in tensile strength and 34% in impact strength compared to those produced by 3D printing. Furthermore, the addition of compatibilizers enhanced the elongation at break by approximately 40% in samples processed through conventional methods.