TEACHERS RESOURCEinstant expert

25 plastic bottles = 1 fleece jacket

Theissues

Resource use - Oil is one of themain raw materials used to

make plastics. Plasticproduction accounts for about

8% of the world’s oilconsumption. Half is used in

transportation and half inproduction.

Landfill - the UK is running outof space to build new landfillsites and as existing sites fill

up we no longer have theoption of burying our plastic

rubbish in a hole and forgettingabout it.

Toxic by-products -indiscriminate disposal ofplastics can release highly

toxic substances, like deadlydioxins, into the environment.

Wildlife impact - 2 millionseabirds die each year due toeating or getting wrapped inplastic. Of the 312 species ofsea bird, 111 are known toingest plastic. In tropical

waters turtles ingest plasticbags mistaking them for

jellyfish, their favourite food. InFrance, a Minke whale was

found stranded on a beach withnearly a kilo of plastic in its

stomach. Not surprisingconsidering that 60% of litterfound on beaches is plastic

(source FOE).

The solutionsReduce plastic packaging where possible; don’t take a plastic bag

if you don’t need one!

Reuse plastic bags and containers rather than buying new ones.Look out for ‘refill packs’ and buy goods made from recycled

goods where possible, for example a fleece made from recycledplastic bottles.

Recycle your plastics by identifying the type of material andputting it into the correct recycling facility. If this isn’t done

correctly the plastic can be ‘contaminated’ and made useless.Recycling saves between 65-80% of the energy required to make

virgin plastic, two thirds of the sulphur dioxide emissions, and halfof the nitrous oxide emissions.

Recycling one plastic bottle saves the energy to run a 60wlightbulb for 6 hours!

The politicsThe EC Directive on Packaging and Packaging Waste sets targets for

member states to recover 50 - 65% of packaging waste, with aminimum recycling target of 15% for each material

(including plastics).

These targets were transposed into UK law via the ProducerResponsibility Obligations (Packaging Waste) Regulations 1997.The new plastic recycling target for 2006 is proposed at 20%.

For more information on the multitude of laws relating to plastics seethe legislation section of the Waste Online website at

www.wasteonline.org.uk

Thefigures

Plastics account for between8-11% (by weight) of waste in

the UK.

60% of domestic plasticwaste comes from packaging

Each of us uses over 90kg ofplastic per year.

A whirlwind tour of issues relating to plastic waste

Takeaction

Try and have a waste freelunch day, so no packed food

(drinks cartons, crisppackets.)

Do a waste audit at school,separate your waste out and

weigh each component(metal paper and plastic)and think how you could

reduce each one.

Get involved in a ‘Clean up’day with a Wildlife Trust or

Marine Conservation Societygroup. If there isn’t one

in your area thenorganise one!

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A Gannet entangled in plastic fishing line

0 20 40 60 80 100

0 20 40 60 80 100

LandfillIncinerated withoutenergy recovery

Incinerated withenergy recovery

Recycled

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Investigating plasticsAimThe aim of these activities is to find out about different plastics. Firstly,by identifying six samples of plastic, and then looking at the uses ofthese plastics. This is a practical activity that highlights why we are sodependent on plastics.

You will need■ 2cm squares of each of the most common types of plastic (one set

for each group)■ A container half filled with water■ Washing-up liquid.

What to do■ Half fill a jar with water. Add the pieces of

plastic and stir. Four pieces of plastic will floatbecause they are lighter or less dense thanwater. They are polyethylene (HDPE and LDPE),polypropylene and polystyrene.

■ Now add a drop of washing-up liquid to the water and stir. Onepiece of plastic (polystyrene) will now sink.

■ The other types of plastic (PET and PVC) will not float because theyare denser than water.

The children should draw up a table with 10 questions (e.g. does itfloat? Is it transparent?) and test each plastic in turn to find out itsproperties. This can then lead on to a discussion about why differentplastics are used for different purposes and why we use so manydifferent types of plastic.

Extension activitiesFind out where your nearest plasticrecycling banks are and what types ofplastic can be recycled there. Draw amap to show others where it is.

Fill two empty margarine tubs with soil.Bury a square of plastic (from a plasticbag) in one and an apple core in the other. Which one degrades first?Try and find a biodegradable plastic bag (from the Co-op or the BodyShop) and see how long it takes to biodegrade.

Make a list of plastic items that can be reused in a useful way. Howmany can you think of? How many of these can you start using atschool or at home?

Write a letter to a manufacturer that you think over-packages itsproducts asking why their products need so much packaging aroundthem, and why the packaging can’t be made from recyclable plastic.

Test whether plastic conducts heat. Place a plastic spoon, a woodenspoon and a metal spoon in a jug of hot water. Feel the handlesfrequently. Which warms up the quickest? Can you tell which is thebest conductor? Which is the worst conductor?

Plastics recycling

TEACHERS RESOURCEprimary years

1 • PETPolyethylene terephthalateFizzy drink bottles and oven readymeal trays. Very similar to PVCbottles but can be identified by ahard white spot in the bottles base.

2 • HDPEHigh-density polyethyleneBottles for milk and washing upliquids

3 • PVCPolyvinyl chlorideFood trays, cling film, bottles forsquash, mineral water andshampoo. Note the absence of ahard white spot in the centreof the bottle’s base.

4 • LDPELow density polyethyleneCarrier bags and bin liners.

5 • PP PolypropyleneMargarine tubs, microwaveablemeal trays. Also used for DVDcases.

6 • PSPolystyreneYoghurt pots, foam meat trays,hamburger boxes and egg cartons,vending cups, protective packagingfor electronic goods and toys.

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TEACHERS RESOURCEsecondary yearsA brief history of plastics1839 – VulcaniteIn 1839 Charles Goodyear added sulphur to latex rubber andproduced Vulcanite, a hard wearing flexible compound whichcould be moulded. It was immediately used to maketyres for the infant car industry.

1870 – CelluloidThis polymer, made by hardeningcellulose nitrate with camphor wasonce used in dentistry and later in thefilm industry. Nowadays celluloid’s onlyreal commercial use is for makingping-pong balls as no other plastichas its unique properties!

1907 – BakeliteA trademark of Baekeland (USA), whocreated a phenolic compound which had amyriad of uses (telephone and radio casings for example).“The word Bakelite” became a generic word of the day for allthings plastic.

The 1930’s Polystyrene (PS) - Large scale production of styrene wasundertaken during World War II, especially for the production ofsynthetic rubbers. Even tougher materials based oncopolymers were introduced in the 1950s, which are now usedin motorcycle helmets and briefcases due to their toughnessand durability. General purpose polystyrene is not the familiarwhite plastic used to protect new electrical goods. One of itsmost familiar forms is used to make the cases for CDs.

Neoprene - neoprene is formedfrom the polymerisation ofchloroprene (which has a similarchemical structure to natural

rubber), and is renowned for its resistanceto chemicals, oil and water. Neoprene became commerciallyimportant in manufacturing protective clothing and wetsuits.

Polyester - trade and political problems between the USA andJapan in the 1930’s made it imperative to find a syntheticreplacement for silk. In February 1935, Wallace HumeCarothers polymerised adipic acid (C6) and hexamethylenediamine (C6) to give ‘Fibre 66’ which had good physicalproperties when it was drawn into a fibre. In September 1938,the material was re-christened Nylon 66. Sadly, Carothersdied before the importance of his discovery was realised.

Polyvinyl Chloride (PVC) - Waldo Semon started thecommercial production of a plasticized vinyl chloride in the1930’s. The material was used for a multitude of productsincluding hollow articles such as squeaky toys and dolls.

Polyethylene (PE) - was discovered largely by accident in1933 by scientists working for ICI. It wasn’t until 1939 thatthis long chain, low density polymer could be extruded as afilm and was christened ‘polythene’.

The 1940’sPolyethylene terephthalate (PET) - Dickson and Whinfieldpatented the reaction of polyethylene glycol with terephthalicacid. PETs became of great commercial importance followingthe development, in 1977, of a mass production technique toblow mould bottles made from the material.

Silicone Polymers – In 1943 the Dow-Corning Corporationstarted production of silicone polymers. Silicone polymershave an unusual combination of properties including waterrepellency, low surface tension, anti-stick properties and hightemperature resistance. They are particularly useful forelectrical insulation and are now essential to communicationtechnologies such as computers, TVs and satellites.

Polypropylene (PP) – Polypropylene is a highly crystallinepolymer produced from propylene, a gas obtained frompetroleum ‘cracking’. It is an important plastic and used inmany different forms. For example polypropylene fibres canbe found in textiles, while a different form is used for thecases of DVDs.

Plastic chemistryMost plastics are made up ofsmall, carbon based moleculescalled monomers. Thesemolecules are joined togetherto form long chains calledpolymers. The long chainstangle together like a ball ofstring, giving plastic its familiarstrength.

For example polyvinyl chloride (PVC) is madefrom many vinyl chloride monomers joiningtogether.

Plastics have different properties and are usedfor quite different purposes. The properties of atype of plastic depend on which monomers areused, how the chains are attached together,and the length of the chains.

Plastics that have strong bonds between chains have higher melting points.With HDPE there is very little side branching on the chains, therefore they cansqueeze together very closely and form strong bonds. However with LDPE thepolymer chains have lots of side branches which means that they packtogether loosely and therefore have weaker bonds. Therefore, HDPE isharder and has a higher melting point than LDPE.

Equation for the synthesis of polyvinyl chloride

Stage 1 Stage 2 Stage 3monomers monomers form tangled not linked into chains called polymers

polymers in plastics

Low density polyethylene High density polyethylene

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When polymers are heated, the chains within them move and cause theplastic to soften. However there are some plastics that do not melt, these areknown as thermosetting plastics.

Thermosetting plastics have strong covalent bonds between their chains.Covalent bonds are where two atoms share the same electron and this resultsin a very strong bond. These plastics do not melt and burn when heated.Burning produces black smoke as un-burnt carbon is released. If themonomer making up the plastics contains other elements, quite dangerousgases can be given off, such as hydrogen cyanide.

TEACHERS RESOURCEuseful websitesWaste Watchwww.wastewatch.org.ukBrilliant website from the leading UKorganisation promoting action onwaste minimisation. Waste Watch willbe publishing a report entitled‘Resource Flow Analysis of Plastics inthe UK’ in Spring 2003 – visit thewebsite to get a copy.

Waste Onlinewww.wasteonline.org.ukCrammed with every conceivablefact about waste issues, includingplastics. This is a ‘must see’ websitefor anyone who wants to know abouttackling the waste problem.

Recycled Products Guidewww.recycledproducts.org.uk A useful database filled withhundreds of products made fromrecycled waste. There is also goodbackground information on buyingrecycled products, logos andaccreditation schemes.

Recycle Morewww.recycle-more.co.ukThis site is provides information onrecycling in the UK. There are areasspecially designed for your home,business and school.

British Plastics Federation www.bpf.co.uk This site covers all aspects of theplastics industry, from environmentalissues to materials and the history ofplastics.

Remarkablewww.remarkable.co.ukA fantastic company which turnswaste vending cups, tyres and milkcartons into recycled stationery.Rubbish has never looked this good!

RECOUPwww.recoup.org A national organisation promotingplastics recycling in the UK, Recoupalso provides educational and trainingtools. A superb resource all round.

Save a Cupwww.save-a-cup.co.uk A recycling company who collecthard-wall plastic vending cupsused in drinks machines andrecycles them.

Marine Conservation Societywww.mcsuk.orgInformation on all aspects of marine

conservation. The MCS also organises‘Beachwatch’ projects to clean upmarine habitats around the UK; a greatway to do your bit for the environment.

Plastics Museumwww.plastics-museum.com A great resource of information, thehistory section is fascinating, and it’sall presented in style.

Wildlife Trustswww.wildlifetrusts.orgLeading UK charity working forconservation of wildlife. Filled withnews and information, this is also agood place to find out aboutconservation activities in your area.

Focus on MaliLocation Mali is a land locked nation in Northern AfricaPopulation approx. 10 millionCapital BamakoGeography Mali is one of the countries where the Sahara

desert and the savannah meet.Main river Niger

Mali and plasticMali’s consumption of plastics provides an interestingcontrast to the UK. Much less plastic is used per person inMali, with a different distribution of the types of plastic used.

Type of Plastic LDPE HDPE PP PVC PS PET Non recyclableTypical Carrier Milk Tubs Squash Cups Pop ElectricalUse bags bottles bottles bottles fittings

UK (%) of total 15% 10% 15% 10% 7.5% 7.5% 22.5%plastic use

UK plastic use 13.5 9 13.5 9 6.75 6.75 20kg/person/year

Mali (%) of total 66% 10% 19% 5%plastic use

Mali plastic use 1 0.15 0.3 0.075kg/person/yearComparison of plastic use in Mali and UK.

The majority of Mali’s plastic is low density polyethylene (LDPE) i.e. plastic bags. Themain associated problems with LDPE in Mali are:■ Sanitary risk – the bags block open wastewater channels allowing stagnant water to build

up, ideal for mosquitoes to breed in and for disease to spread.■ Soil degradation – the bags enter the soil, reducing the soil’s permeability and ability to

absorb water.■ Herd animals often eat the plastic and can die.■ As there is no formal waste disposal people burn plastic in the street. This has negative

health impacts.

End use of plasticsMali has a very efficient informal recycling network with virtually 100% of the

Polypropylene (PP) and PVC being recycled. Firstly, plastic is collected or purchaseddoor to door and sorted by type. Then the plastic is washed and non plastic material

removed. Finally, the plastic is shredded injection moulded or extruded into new shoes,drainpipes, or wire insulation. It is likely that over 1000 people scrape a living

collecting and reprocessing PVC and PP.

All the information you need is out there on theinternet – somewhere! We tell you where to look.

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