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Understanding packaging and the language we use to describe it The way a plastic is designed This document sets out to clarify the differences Contents to behave alongside what between the materials used Material type 3 to make plastic packaging, Behaviour and features 4 material it’s made from, the way can behave affects what it can be used and, the terminology used Suitability for 5 for as well as how it can be to describe plastics. Treatment and disposal route 6 Environmental impact 7 recycled and disposed of at Carbon footprint over life cycle 8 the end of its life. Glossary 9 References 10

With plastics top of the sustainability compostable – and the effect these agenda many companies are looking factors have on how it’s collected at alternatives to conventional and disposed of. plastic typically used for packaging applications. Understanding the terms that we use to describe plastics is essential However, there is potential for the to ensure that the right materials language that we use to describe are used in the right applications, plastics to be confusing: with the and so that all plastics are recycled different material types of plastic – in the right way and pollution of fossil-based or bio-based; how the environment is prevented. plastic is described and referred to – conventional plastics or bioplastics; This document is aimed at anyone and, how plastic behaves – non- who is interested in understanding biodegradable, biodegradable or the complexities around different types of plastic.

WRAP | Understanding plastic packaging 1 Plastic can be made from fossil-based This diagram demonstrates the or bio-based materials. Both can be complexity of the term bioplastics; used to make highly durable, non- which refers to a diverse family of biodegradable plastics, or plastics materials with differing properties – Bio-based which either biodegrade or . there are three main groups:

The nature of the material used 1 Bio-based or partially bio-based to make a plastic or the term used non-biodegradable plastics such to describe it does not necessarily as bio-based PE or PP 1 2 dictate the way it will behave at the end of its life e.g. a bio-based plastic 2 Plastics that are both bio-based Bioplastics Bioplastics or bioplastic does not automatically and biodegradable, such as eg. PE, PET, eg. PLA, PHA, PBS, mean it will biodegrade. biodegradable PLA and PHA PA, PTT blends or PBS Biodegradable 3 Plastics that are fossil-based and biodegradable, such as PBAT

See glossary for acronyms.

3 Non biodegradable Conventional Bioplastics plastics eg. PBAT, PCL eg. PE, PP, PET

Fossil based

WRAP | Understanding plastic packaging 2 Material type

Fossil-based plastic Bio-based plastic Made from a wide range of polymers Made using polymers derived from derived from petrochemicals. Fossil- plant based sources e.g. starch, based plastic packaging is generally , oils, lignin etc. long lived, durable and non- biodegradable; this is what’s referred Bio-based plastic is the term used to as conventional plastics. However, for any plastic made from bio-based fossil-based plastic can also be polymers, and refers to the source designed to biodegrade and this from which the plastic is made, not type is considered a bioplastic. how the material will function. IMAGE? Bio-based polymers can be used to make plastic packaging that behaves like conventional plastic and is long lived, durable and non-biodegradable. It can also be used to make biodegradable and compostable plastics. Both types are referred to as bioplastics (see diagram on page 2).

WRAP | Understanding plastic packaging 3 Behaviour and features

All plastics, regardless of whether they are fossil-based Non-biodegradable Biodegradable Compostable or bio-based, can be designed Is durable and lasts for years. Breaks down in a defined period Can meet EN13432 or a comparable to behave in three ways: of time. standard for compostable packaging It has high strength and can be used so that the material decomposes/ in low weight applications. It can now be made with similar biodegrades in industrial composting strength, plasticity and elasticity conditions. Materials that meet properties of non-biodegradable an appropriate home composting plastics, and made into products standard can be composted in using the same technologies home composting systems. (e.g. film processing or moulding). It can have similar strength, plasticity The fact that a plastic is described as and elasticity properties to non- biodegradable does not mean that biodegradable plastics and can be it should be freely released into made into products using the same the environment in an uncontrolled technologies (e.g. film processing manner. The speed, method and or moulding). nature of differs between materials and users should question the behaviour of biodegradable materials before using them in any application.

Importantly, not all is compostable, but all compostable plastic is biodegradable.

WRAP | Understanding plastic packaging 4 Suitability for recycling

The way a plastic is designed to behave dictates Non-biodegradable Biodegradable Compostable its suitability for recycling – Non-biodegradable packaging Currently biodegradable plastics Compostable plastics can be not whether it is fossil-based plastics can be recycled, if collected cannot be recycled in the same way composted at industrial scale or bio-based. and sorted into separate material as non-biodegradable plastic. composting facilities or, in some reprocessing streams. cases, may be suitable for home It must be separated from non- composting. It is vital that only The route for recycling or disposal biodegradable plastic streams and compostable plastics are sent to must not compromise other recycling dealt with separately. If not, it causes these routes as non-compostable routes. Non-biodegradable plastics problems during the recycling plastics can contaminate the final entering the composting processes process. compost produced. can contaminate the final product. Biodegradable packaging needs to be Compostable plastic packaging clearly labelled and easy for citizens needs to be clearly labelled and easy to identify, separate and correctly for citizens to identify, separate and dispose of. The route for treatment correctly dispose of in an appropriate and disposal must not compromise collection and recycling scheme for other existing recycling routes. compostable plastics. The route Biodegradable packaging can only for recycling compostable packaging be composted when it meets the must not compromise non- appropriate composting standard. biodegradable recycling routes.

WRAP | Understanding plastic packaging 5 UK treatment and disposal routes

Non-biodegradable Biodegradable Compostable

Recycling

Energy from waste

Landfill

++ AD * * *

Composting **

* Any non-biodegradable, biodegradable or compostable packaging sent to wet AD systems that do not include a composting step for the treatment of digestate in the UK will be removed during pre-treatment of the feedstock material and sent to landfill or energy from waste. ** Plastic packaging can only go to industrial composting if it complies with the EN13432 compostable standard or a recognised home composting specification. It can only be composted at home if it complies with a recognised home composting specification. ++ Compostable packaging can be accepted at dry AD systems that can process the material fully or at wet AD sites where the process includes a composting step for the treatment of the separated digestate fibre.

WRAP | Understanding plastic packaging 6 Environmental impact

Any plastic that evades appropriate collection and treatment that escapes into the environment has the potential to have a long-lasting impact on the environment.

Non-biodegradable plastic Biodegradable and packaging compostable plastic packaging Conventional plastic debris has been shown to accumulate in inland waters There is a lack of clarity concerning and marine environments. The impact standards that define the of this is now being widely discussed. biodegradability of biodegradable or compostable plastics in any There is very limited information environment. There is a particular on the impact of conventional plastic lack of evidence on the behaviour of in soil-based environments, though these materials in water, and there is it is clear that plastic fragments will a need to understand biodegradation persist for long periods of time. at lower temperatures. Therefore, it is very difficult to accurately assess environmental impact of biodegradable and compostable plastic packaging.

WRAP | Understanding plastic packaging 7 Carbon footprint over life cycle

Life Cycle Assessment is a complex technique to quantify the environmental impact of a single product over its whole life cycle.

For from The opposite is true for biodegradable all types of plastic, studies show that plastics, which has the potential to raw material extraction, production, give rise to methane under landfill and waste disposal contribute most to conditions, but in energy recovery emissions. Bio-based plastics usually are considered carbon neutral have a lower carbon impact in their (short cycle emissions). extraction and production phase. Compostable plastics contribute Where conventional plastics enter to compost structure, but contain energy from waste facilities, they no nutrients (NPK). emit greenhouse gases, which can be higher than combusting coal or For all plastics, recycling generates to generate the same the lowest emissions at end of life. amount of energy. In landfill they are considered inert.

WRAP | Understanding plastic packaging 8 Glossary

Biodegradable Compostable PBAT and PBS PE A product that can be broken down Compostable materials are materials terephthalate – a type of resin and by microorganisms ( or fungi) that break down at composting and Polybutylene succinate – two a and one of the world’s into water, naturally occurring gases conditions. Industrial composting biodegradable (Muthuraj most widely produced synthetic like carbon dioxide (CO2) and conditions require elevated et al 2014). plastic. High density PE is used for methane (CH4) and . temperature (55-60°C) combined milk , bleach, cleaners and Biodegradability depends strongly with a high relative and Recycling most shampoo bottles. Low density on the environmental conditions: the presence of oxygen, and they are PE is used for carrier , bin liners Material recycling is defined in temperature, presence of in fact the most optimal compared and packaging films (WRAP 2018). European standard EN 13430 and microorganisms, presence of oxygen to other everyday biodegradation EN 16848 (adapted from ISO 18604) and water. The biodegradability and conditions: in soil, surface water and as the reprocessing of a used product PHA the degradation rate of a marine water. Compliance with EN material into a new product. Plastic Polyhydroxyalkanoate – A naturally biodegradable plastic product may 13432 is considered a good measure which after use can be collected, occurring family of biodegradable be different in the soil, on the soil, for industrial compostability of sorted and reprocessed into new polyesters (NNFCC 2018). in humid or dry climate, in surface packaging materials. products is called mechanical water, in marine water, or in human recycling. Another option is chemical made systems like home composting, PLA Home composting recycling where materials are broken industrial composting or anaerobic – A biodegradable Home composting creates conditions down to which can be used digestion (www.ows.be). produced from lactic acid, with much lower and less stable again for the production of polymer. used in wide range of serviceware temperatures than industrial products and as filament for 3D composting. There is no CEN standard (NNFCC 2018). for plastics that are suitable for home composting but several countries Industry example: PG Tips is using have developed and applied national PLA for their tea bags (NNFCC 2018). standards for testing and certifying of home compostable materials.

WRAP | Understanding plastic packaging 9 Glossary

PP PET PA Starch blends – a recyclable Polyethylene terephthalate is a type (Nylon) comprise the The majority of bio-based plastics are polyolefin that is commonly used for of resin and a form of polyester; largest family of engineering plastics currently manufactured using starch margarine tubs, microwaveable meal it is commonly labelled with the code with a very wide range of applications. as a feedstock (c.a. 80% of current trays, also produced as fibres and on or near the bottom of bottles Polyamides are one of the major bio-based plastics). The current major filaments for carpets, wall coverings and other . PET has some engineering and high performance sources of this starch are , and vehicle upholstery (WRAP 2018). important characteristics such its plastics because of their good balance potatoes and cassava. Other strength, thermo-stability, gas barrier of properties. Polyamides are very potential sources include arrowroot, PTT properties and transparency. It is resistant to wear and abrasion, have barley, some varieties of liana, millet, also lightweight, shatter-resistant good mechanical properties even at oats, rice, sago, sorghum, sweet Polytrimethylene terephthalate is and recyclable (WRAP 2018). elevated temperatures, have low potato, taro and wheat (BPF 2018). a type of polyester that differs from permeability to gases and have good the common one polyethylene chemical resistance, good dimensional terephthalate (PET) as it contains one PLC stability, good toughness, high more methylene group in the aliphatic is a biodegradable strength, high impact resistance, chain that links the terephthalic polymer that is suitable for good flow. moiety (European Commission Joint applications requiring years of Research Centre 2013). stability. In recent years it is becoming of increased interest to manufacturers of medical devices and drug delivery particles (polysciences.com 2018).

WRAP | Understanding plastic packaging 10 References

Defra (2015) ‘Review of the standards for WRAP (2010) Life cycle assessment of example biodegradable plastic carrier bags’. Available at: packaging systems for milk http://www.wrap.org. https://www.gov.uk/government/uploads/system/ uk/sites/files/wrap/Final%20Report%20Retail%20 uploads/attachment_data/file/485904/carrier-- 2010.pdf biodegradable-report-2015.pdf (Downloaded on the 26/01/2018). Umweltbundesamt (German Federal Environment Agency) (2013) Study of the Environmental Impacts PAS600:2013 Bio-based products. Guide to of Packagings Made of Biodegradable Plastics standards and claims https://shop.bsigroup.com/ https://www.umweltbundesamt.de/sites/default/ ProductDetail/?pid=000000000030262005 files/medien/461/publikationen/4446.pdf

DEFRA (2011) study on plastic bags can be found Piemonte, Vincenzo & Gironi, Fausto. (2012). here and a figure illustrating the global warming Bioplastics and GHGs saving: The land use change potential of each type of bag included in that study (LUC) emissions issue. Energy Sources, Part A: is included at the end of this table. (Defra https:// Recovery, Utilization, and Environmental Effects. www.gov.uk/government/uploads/system/ 34. 1995-2003. 10.1080/15567036.2010.497797. uploads/attachment_data/file/485904/carrier-bag- biodegradable-report-2015.pdf Bioplastics diagram based on the European Bioplastics version https://www.european- WRAP (2010) Environmental Benefits of Recycling bioplastics.org/bioplastics/materials/ 2010 update http://www.wrap.org.uk/content/ environmental-benefits-recycling Wageningen Food & Biobased Research (2017): Biobased and biodegradable plastics – Facts and Figures – see link below https://www.wur.nl/upload_ mm/e/6/8/113a1607-0925-4829-b864- f0e6a5fc79c5_170419%20Report%20Bio-based%20 Plastic%20Facts.pdf

WRAP | Understanding plastic packaging 11 WRAP’s vision is a world in which resources are used sustainably.

Our mission is to accelerate the move to a sustainable resource efficient economy through reinventing how we design, produce and sell products; re-thinking how we use and consume products; and re-defining what is possible through re-use and recycling.

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WRAP | Understanding plastic packaging