Potential use of Recycled Plastic Bags in Rotational Molding Process

Abstract

Plastic bags are one of the most widely used products because it can provide convenience to users in everyday life. As a result, the amount of waste from plastic bags after use increases every year. The objective of this research is to study the preparation of used plastic bags to be in a suitable form for recycling by the rotational molding process. Including the study of various properties of molded products by using plastic bags that have been used in Pathum-Thani area, most of them are Low Density Polyethylene (LDPE) compared to Linear Low-Density Polyethylene (LLDPE) used in the rotational molding industry. In this research, the material for molding must be prepared by reducing the size of plastic bags to the powder particles by a Pulverizer, as well as measuring the particle size, roundness (Circularity) by morphological techniques. The pourability bulk density and melt flow index of the particles were tested and molded by an Axial Powder Flow Apparatus with the rotation speed at 7 rpm, temperature 190°C and recorded the behavior of changes within the mold and test the molded specimen by measuring the thickness distribution of the specimen, puncture resistance, tensile strength and surface hardness. It was found that the particle size of plastic powder prepared from plastic bags was larger and less roundness compared to the particle size of LLDPE powder used in the rotational molding industry. As a result, the thickness distribution of the workpieces produced with powder particles from plastic bags is inferior and the penetration resistance, tensile strength and surface hardness are reduced compared to using LLDPE.