Diego Piazza
University of Caxias do Sul, Brazil
Title: Recyclability of polypropylene (PP) and polyethylene (PE) waste from the Hawaii coastline
Biography
Biography: Diego Piazza
Abstract
Introduction: One of the major environmental problems is the ocean pollution. It is estimated¹ that the oceans’ surface holds more than 13.000 polymer fragments/km2. These fragments harm the fauna, since animals’ mistake polymers for food leads to death nearly 100 thousand marine mammals every year2. Synthetic polymers are inert towards degradation, this way, the material tends to accumulate in the oceans as a result of the huge consumption of polymers. This work aims to develop a methodology to recycle polymers found in oceans, comparing their mechanical and rheological properties with virgin polymers.
Experimental :The polymers employed in this work were collected on the beach sand of Kamilo Beach, Hawaii with the help of the The Ocean Cleanup team. Among the collected polymers higher amounts of PE and PP is highlighted. After clean and dried, they were ground in a knife mill. The resulting product had an average particle size distribution of 2 cm and was separated according to different densities. Afterwards the polymers were extruded in a single-screw extruder at the temperature profile of 170/185/200°C for PE and 180/195/210°C for PP. Afterwards, test specimens were obtained by injection, and then submitted to the flexural strength (ASTM D790), and melt flow index (performed under 190°C, 5Kg and 20s for PE; 230°C, 2.16 kg and 10s for PP) tests.
Results: Data obtained for the modulus of elasticity and melt flow index for PP and PE waste had values close to those of the respective commercial virgin resins.
Conclusions Based on the obtained results it is concluded that although the polymers has been exposed to different weather conditions, PE and PP waste can be recycled and bear properties which enable them to be used in the production of new products
