Ultraviolet stability of mixed waste plastic composites

Abstract

Plastic waste disposal is one of the most challenging problem of the current era. It is non-degradable, causes soil and water pollution and thus have a dangerous impact on nature and mankind alike. Until 2018, most of the plastic waste from developed countries were sold or sent to China for further treatment; however, since then, China has imposed an import ban on many types of plastic waste coming from abroad. This directly led to an influx in plastics waste in various sorting centers across many waste exporting nations. Additionally, Waste Framework Directive set up by EU is compelling EU members to find new ways to recycle municipal solid waste (MSW) These political changes opened a big field for different research works to find efficient ways of how waste could be recycled. It has been well documented that increase in plastic waste is directly related to world’s population growth, which in turn leads to more plastics production for consumers to use every year. The main issue is to separate different plastic grades from each other. On solution can be blending a mixture of different plastics grades thus saving energy, time and resources.

In order to protect the color and structure of the plastic material in outdoor applications, it is important to use ultraviolet (UV) stabilizers. Tinuvin 770 DF HALS and Chimassorb 81 UVA light stabilizers were added to the plastic blends. CIELAB spectrophotometer test was applied after accelerated weathering with a xenon lamp, where Chimassorb 81 stabilizer showed better results. The tensile test showed that the addition of UV stabilizers also affects the mechanical properties of the samples after accelerated weathering tests. Tensile modulus results of the samples with UV stabilizers display higher value compared to samples without UV stabilizers. Overall mixed plastic waste showcases a good level of mechanical properties similar to LDPE pure plastic grade. Hence there is good potential for recycling mixed plastic waste.