However, polyethylene, or more commonly, used for polythene plastic bags is just one of many plastics used. The plastic used for adhesive tape, shower curtains and some clothing is PVC. It can also be a hard plastic, and over 50% of PVC is used in construction because it's so cheap and easy to assemble. The gramophone records that were popular before CDs came along, and are often called vinyl records because they are made from PVC: Polyvinyl chloride. The disposal of PVC causes problems because if burned it releases toxic fumes and if land filled it releases additives which can threaten groundwater supplies. PVC cannot be recycled to the same quality and most is ' downcycled ' to make inferior products such as garden furniture.
đang được dịch, vui lòng đợi..