pps proceeding - Abstract Preview
pps proceeding
Symposium: S21 - Special Symposium: Biopolymers, eco-friendly polymers and recycling
Oral Presentation
 
 

The effect of Polypropylene-based Olefin Block Copolymer and organoclays in Recycled HDPE/PP nanocomposites

Rigail-Cedeņo Andres F (1)*, Diaz-Barrios Antonio (2), Alban Bolivar (3), Lazo Miriam (1), Molina Vanesa (1), Caceres Julio (1), Pilataxi Jose (1)

(1) ESPOL Polyethnic University Escuela Superior Politecnica del Litoral - Guayas - Ecuador, (2) Yachay Tech - Urcuqui - Ecuador, (3) Bactechnology - Guayas - Ecuador

The circular economy promotes the recycling of plastics to develop new materials and products. The blends of immiscible plastics increase the availability of raw materials. This research aims to process and relate the morphology, rheological and thermo-mechanical properties of recycled high density polyethylene (HDPE) and recycled polypropylene (PP) modified by the addition of commercial organoclays and polypropylene/based olefin block copolymer (POBC) compatibilizer. Given amounts of post-consumer blends of rHDPE coming from packing and rPP from lids were mixed in a torque rheometer. In order to determine the amounts of these plastics in the blends, mixes of virgin HDPE and PP in percentages of 0, 20, 40, 60, 80, 100 wt% were prepared, and the corresponding DSC calibration curve of enthalpy of fusion versus concentration was obtained. The resultant blend of rHDPE/rPP (~83 wt%/~15 wt %) was melted with two organoclays (Cloisites20A and Cloisite 93A) (3 wt%) and with or without the presence of POBC (Intune 5541) ( 5 wt%). Intercalated structures were observed in both clay nanocomposites, but Cloisite 20A showed greater basal spacing than those of Cloisite 93A. It was found that the organoclays and the POBC decreased the crystallinity on rHDPE and rPP. Rheological measurements using a plate-plate rheometer showed a viscosity increase of blends in the presence of both organoclays, at low shear rates (~ 10 s -1), being the Cloisite 20A the one that showed the highest values. On the other side, the POBC decreased the viscosity in all composite blends, at higher shear rates (60-100 s-1). Both organoclays increased the stiffness of the rHDPE/rPP, but the POBC in conjunction with the organoclays declined the stiffness. The impact resistance was increased in the presence of the organoclays and the POBC. Based on these results, it can be concluded that the two organoclays used in this study can be used as compatibilizers for rHDPE/rPP blends.