This chapter looks at the production of plastic and the recycling of plastic from an industrial point of view. Overviews are given of worldwide plastic production and the management of plastic waste. The recycling of plastic is looked at in-depth from the point of view of collection, recycling facilities, current advances, economic issues, and finally challenges and opportunities for improving plastic recycling.

Plastics are being manufactured globally at a rate exceeding 335 million tonnes annually and 8.3 billion tonnes have been made since the 1960's, with 4.9 billion tonnes accumulating in landfills or in the natural environment. The leakage of mismanaged plastics into rivers and oceans is now globally obvious and impacting the lives of birds and sea life. The recycling rate of manufactured plastics is only 9% and there is pressure to reduce the level of wastage and to dramatically increase the level of recycled plastics in short and long term products. This will involve stringent and tightly controlled recycling processes so that the recycled plastics can displace virgin plastics, especially in short lived applications such as food packaging. This article reviews the technologies and criteria that can be used to achieve food grade quality recycled plastics and novel ways of overcoming long standing gaps in recycling related to black plastics and identifying prior food grade usage. The boost in recycling efficiency through the use of these technologies will not only address the plastics wastage problem by creating a circular demand via higher recycled content, but also make plastics recycling technically more efficient and profitable thereby ensuring wide and long term adoption of recycling practices.

The majority of disposable cups are made from paper plastic laminates (PPL) which consist of high quality cellulose fibre with a thin internal polyethylene coating. There are limited recycling options for PPLs and this has contributed to disposable cups becoming a high profile, problematic waste. In this work disposable cups have been shredded to form PPL flakes and these have been used to reinforce polypropylene to form novel paper plastic composites (PPCs). The PPL flakes and polypropylene were mixed, extruded, pelletised and injection moulded at low temperatures to prevent degradation of the cellulose fibres. The level of PPL flake addition and the use of a maleated polyolefin coupling agent to enhance interfacial adhesion have been investigated. Samples have been characterised using tensile testing, dynamic mechanical analysis (DMA) and thermogravimetric analysis. Use of a coupling agent allows composites containing 40 wt.% of PPL flakes to increase tensile strength of PP by 50% to 30 MPa. The Young modulus also increases from 1 to 2.5 GPa and the work to fracture increases by a factor of 5. The work demonstrates that PPL disposable cups have potential to be beneficially reused as reinforcement in novel polypropylene composites.