Recycling of Waste Plastics at Fish Market in Taiwan

摘要

Among the plastic wastes generated at the fish markets in Taiwan, expandable polystyrene (EPS) is the most abundant. The rests are high-density polyethylene (HDPE) and pure polypropylene (PP). Because the majority of plastic wastes are normally dumped and mixed together, that makes them difficult to separate. Therefore, it is becoming a serious problem to recycle the waste plastics offish markets. To solve the problem, a polyblending is applied to recycle those plastics that have different melting points at the same time in this study. The objective of this paper is to present the contribution of the study in improving the physical properties of the recycled materials by a polyblending method. Differential Scanning Calorimetry (DSC) measurements and Scanning Electronic Microscopy (SEM) observations show that EPS, PP, and HDPE with all blending ratios were not well compatible. Tensile strength tests revealed that the Young's modulus (E) of polyblends of EPS with PP or EPS with HDPE were decreased with the increase in PP or HDPE content. The experimental results also indicate that those relatively tough PP or HDPE decreased the brittle property of EPS and increased its toughness. However, in the polyblends mixtures of EPS, PP, and HDPE, the Young's modulus (E) reached the lowest value, highest toughness, when EPS was 60% and the total amount of PP and HDPE was 40%. It means that those relatively tough materials, i.e. PP and HDPE can't change the intrinsic brittle property of EPS absolutely. The findings mentioned above may be explained by the so-called "string-twisting effect" phenomena.