Mechanical Properties of Recycled Plastics

Recycled plastics mainly obtained from two primary methods i.e., mechanical and chemical processes. Between these two methods, the mechanical method that goes through physical processes is commonly used instead of the chemical method. Physical processes usually involve heat, mechanical stress, and oxidation, resulting in plastic degradation. The degradation of plastic will affect the molecular structure of the plastic and thus result in the change of plastic properties, especially in mechanical properties. It is interesting to look over every mechanical property change that takes place on recycled plastic. The change involves negative changes, but there are also positive changes in which the mechanical properties improve with recycling. The difference in the mechanical properties of virgin plastic and recycled plastic depends on the recycling cycle frequency. Most of the first recycling cycle plastics do not show significant feature changes compared to virgin plastics. Meanwhile, plastics that undergo several reprocessing show substantial changes in the mechanical properties. Therefore, the more recycling process cycles, the more noticeable difference in mechanical properties displayed by recycled plastics compared to virgin plastics. This chapter explores the various mechanical properties of recycled plastic in detail.