:: Specific Design Brief

: Reduce, Reuse, Recycle


Plastics are extensively recycled in many countries, with 41% of households in the UK having access to plastics recycling facilities.

It has been recommended for many years that reducing, reusing and recycling provide many opportunities for environmental improvements in our own and other countries and in product manufacture. Design and make a product that uses at least one of those criteria.

Environmental legislation known as the Waste Electrical and Electronic Equipment (WEEE) Directive will come into effect in August 2006. The WEEE directive aims to reduce the amount of waste electrical and electronic equipment currently put into the regular waste stream.

It means that many companies who manufacture electrical and electronic products (e.g. cookers, telephones, musical socks, watches) will be required to take back old products, and disassemble them to reclaim materials and components for recycling or reuse.

Traditionally this has been done automatically (which is cheap but involves crushing the product) or by hand (which is expensive, but means that fragile components can be removed). A more cost effective way of taking a product apart carefully, is to use smart materials in the design of the product. When treated in a specific way (e.g. heating, cooling) smart materials can be made to expand, contract, melt, and change colour. These smart materials can be used to force the product casing apart, and communicate useful messages regarding material types etc.

Identify a type of product which would benefit from being disassembled at the end of its life (i.e. to reclaim valuable materials and/or components for reuse or recycling). Then using one or more smart materials, design a system which will enable the product to be automatically disassembled at the end of its life.

Environmental legislation for electrical and electronic products from August 2006:

WEEE will require that a certain percentage of all electronic and electrical products sold, are collected by the manufacturer for recycling and disposal.

Large household appliances 80%
Small household appliances 70%
Consumer equipment 75%
Tools 70%
Toys 70%
IT and telecoms 75%
Lighting 70%
Monitoring & controlling equipment 70%
Automatic dispensers 70%

(Source: ICER, 2001)

WEEE will require that a certain percentage of all electronic and electrical products sold, are reused or recycled.

Large household appliances 75%
Small household appliances 50%
Consumer equipment 65%
Tools 50%
Toys 50%
IT and telecoms 65%
Lighting 50%
Monitoring & controlling equipment 50%
Automatic dispensers 50%

(Source: ICER, 2001)

Types of Smart materials available:
The types of smart materials that you can use can be found at www.tep.org.uk

Examples include:

Polymorph: This polymer has all the characteristics of a tough “engineering” material yet it fuses and becomes easily mouldable at just 62°C. It can be heated with just hot water or a hairdryer and moulded by hand.

A 5mm dia. x 12mm (when closed) spring made from shape memory alloy. At room temperature this spring is soft enough to pull out to approximately 50mm by applying a small force. When heated to 70°C by passing an electric current through it, the spring contracts to its original length with a useful pulling force (equivalent to lifting a 0.5kg weight).

Thermochromic pigment is made up as a liquid paste compatible with any acrylic media. At normal room temperature the pigment appears coloured but at 27C the colour disappears. E.g. If the black thermochromic pigment is applied to a white surface, the surface turns from black to white at the change over temperature.

Some issues that the design must address
• appropriate product selection
• the value of the components/ parts to be retrieved after disassembly
• safety issues – the product must not come apart by accident whilst still in use
• acceptable cost to manufacturers

The non-destructive disassembly of products allows separation of whole components and sub-components allowing very high purity of recycled parts and thus higher profit for recyclers and thus less cost implications for the manufacturers.

The following types of products might benefit from active disassembly with smart materials:
• Telephones
• Mobile phones
• Component assemblies
• Cameras
• Calculators
• Electronic games
• Personal organisers
• Battery chargers
• Computer casings
• Mice and keyboards
• The process is especially suited to small or medium sized plastics dominated products with its ability to provide a high purity plastics waste stream and easy separation of the electronic component with minimal input energy. Markets for recycled plastics are increasing with value heavily dependent on polymer granulate purity.

Chiodo, J. D., Billet, E. H. and Harrison, D. J. (1999a) Active Disassembly using Shape Memory Poymers for the Mobile Phone Industry. In IEEE International Symposium on Electronics and the Environment - ISEE - 1999,Danvers, Massachusetts, 11 - 13 May 2020, pp. 151 - 156.
Chiodo, J. D., Billet, E. H. B. and Harrison, D. J. (1999b) Preliminary Investigations of Active Disassembly Using Shape Memory Polymers. In EcoDesign '99.