Design: Material Worlds: Plastic: Shaping reality: We live in a plastic world: this old sneer expresses a basic truth. From Bic razors to artificial hearts, Swatch watches to jetliners, modern life is moulded by the stuff

IF HERALDIC designers were ever asked to dream up a new coat of arms for London, the plastic bin-liner might feature large in their commission. Ranged along the walls of historic buildings and squatting in festering heaps along the main thoroughfares, the bin-liner - black in much of the capital and fluorescent green in the City of Westminster - is as much a part of the fabric of contemporary London as McDonald's, trainers and baseball caps.

Now that Harrods sells its own deluxe green and gold bin-liners (10 for pounds 3.25), the rubbish bag has become a luxurious celebration of urban waste. It is also one of the countless plastic artefacts we have come to rely on. Did we really once throw rotting vegetable waste unwrapped into our dustbins and expect someone else to empty it into a dustcart?

The bin-liner, like so many of the plastic products we depend on, sanitises the modern world. We wrap our food in plastic, bottle our water in it, cover precious goods in the stuff to protect them from the perils of transport and handling. We conceal the electronic entrails of our radios, televisions and computers behind plastic; we write with plastic pens; we even allow surgeons to replace our vital organs with plastic replicas. And yet we still use the word plastic to denote tackiness and cheapness. We say things are 'plasticky', meaning disposable and therefore bad, even though some of the most finely-produced goods available are made of this ubiquitous polymer.

Why is this? Because we believe that natural materials are not only more pleasing to look at and to touch, but also that they are 'greener'. While to a great extent this is true, plastic plays practical, life-enhancing and even life-preserving roles in our lives. Scientists, meanwhile, are learning how to recycle this complex and extensive clan of artificial materials derived from the oil, petrochemical and fertiliser industries.

From an aesthetic point of view, plastic has come a long way since its prototypes Bakelite (a resin invented in the United States by the Belgian-born engineer L H Baekeland, 1863- 1944) and Perspex (a clear acrylic resin used as a lightweight alternative to glass) surfaced in the 1930s. In familiar consumer products such as Braun alarm clocks (designed by Dieter Rams) and Swatch watches (made by robots in Switzerland), plastic is used precisely and attractively. From the late Fifties, architects and designers made use of new developments in plastic technology to create furniture that owed nothing to precedent. Their startling new forms had a beauty of their own. Even today such designs as the RAR-1 rocking chair (1950) by Charles Eames for the US company Herman Miller or the Tulip Chair (1957) designed by Eero Saarinen for Knoll International, seem innovative and fresh.

In the experimental Sixties, plastic allowed the imagination of designers full rein; out went plywood, the stock in trade of the avant-garde designers of the Fifties, and in came such malleable new plastics as polypropylene, invented by Giulio Natta in 1954. The advantage of polypropylene is that it can be injection-moulded, allowing designers to create any number of forms, both functional and fantastic.

On the functional side, Natta's plastic resulted in the classic Polypropylene Chair (1963) designed by Robin Day for Hille International - a low-cost chair familiar in halls and schoolrooms across the world. Pop designers, meanwhile, adopted new plastics to create weird and wonderful furniture: transparent armchairs, chairs in the shape of eggs and spheres; a laboratory of new plastics was made over to the creation of bizarre furniture. Many of these designs were batty, but few of them were tacky.

Yet although new plastics allowed designers freedom to create radical shapes, there were at least two key problems that stopped plastic furniture from sustaining the popularity it attained in the 1960s. The first was that plastic furniture could not be made without heavy investment in the equipment needed to mould, inject or otherwise form the new material; unless production runs were enormous, as in the case of Robin Day's Polypropylene Chair, plastic furniture was therefore expensive to buy. The second was a question of ecology. New petroleum-derived materials (of which plastic is one) and other artificial materials, including foam-rubber, were proving to be both toxic (very dangerous if set on fire) and difficult to recycle. Anyone who, as a child, set fire to an Airfix Spitfire or Messerschmitt before catapulting it out of the bedroom window, will remember the dense black fumes it trailed in its wake, scattering cats and birds unfortunate enough to witness this toxic destruction.

Nevertheless, because plastic is so easy to work - it can be moulded to any shape and is easy and cheap to mass-produce - we have come to rely on it. And a material that was once considered either a novelty or a second- rate, low-cost alternative to natural materials is now used as a very refined material in the best factory-made goods.

The dashboard of a contemporary BMW and the casing of a Braun alarm clock are examples of plastic used well: BMW does not need wood in its cars - the plastic it uses is not at all 'plasticky'. The fact that the company does feel the need to decorate the interiors of its top-line saloons with timber reflects the fact that luxury is associated with natural materials. But curiously, along with German, Japanese and American manufacturers, BMW makes its wood look exactly like plastic, covering it in so much plastic-based varnish that the natural qualities of the material vanish altogether.

Where did our mistrust of plastic come from? Why has the material such a lowly reputation, when the simplest Bic biro is a far finer artefact than most of the knock-together wooden furniture we buy? The most probable answer is that in its early days, plastic was nearly always employed as a substitute, dressed up as wood and other materials.

Equally, plastic - when it came into its own - was associated by the high-street consumer with tacky transistor radios and other nasty, noisy, consumer disposables (including all those disgusting 'Empire Made' toys that children found in 'Jamboree Bags' and Christmas crackers). It was almost bound to be condemned. How many writers of the Fifties and Sixties described our world as 'plastic'?

Yet plastic has its own qualities and they have only gradually come to be appreciated. The uncoloured plastic components that make up the structure, as well as the detail, of contemporary aircraft, cars and buildings are not to be despised. The word itself has a noble history; we talk of the 'plastic arts' (sculpture, in particular) and of 'plastic surgery'. Plastic derives from the Greek plastikos (to mould) and today we use plastic increasingly to give shape to our everyday world.

Modern plastic is a Hydra-headed beast. It is not one material, but many, ranging from polythene and Plasticine to polypropylene. There is, of course, a common denominator: all modern plastics are synthetically-derived polymers, that is, materials that have no fixed shape or size; their molecular structure means that they can be processed ad infinitum. (A polymer is 'a compound', says the OED, 'whose molecule is formed from a number of repeated units of one or more compounds of low molecular weight').

So, unlike iron or wood, plastic is distinctly unimpressive in its raw state. It is the stuff of laboratories rather than forges and forests. It has no particular smell and, until moulded and coloured, is as amorphous and as uninteresting as a pile of dust.

But then plastic was never intended to be glamorous. Its first venture onto the mass market, in the form of Bakelite, was for use in the electric insulators required by the new wireless and telecommunications industries. Although heavy and brittle compared with later plastics, Bakelite was easy to shape into the new gadgets associated with the consumer end of these new ventures: telephones, wirelesses and so on.

As product designers (a new breed which grew up with the rise of plastics) got their hands on these latest gadgets, they found Bakelite an excellent material with which to indulge their formalistic fantasies. The plastic properties of Bakelite, coupled with the wilfulness of art deco, led to fantastic and even freakish designs - of radios, car interiors, early televisions and cocktail cabinets. Because it could be formed into virtually any shape and produced in a rainbow of colours, Bakelite was the darling of designers of bar, nightclub and Hollywood set. Today it retains a certain appeal for those who revel in Thirties kitsch.

The Second World War drove chemists on to produce the highly malleable, lightweight plastics we have taken for granted ever since. Fighter pilots knew the virtues and weaknesses of Perspex, a glass substitute which, although light, scratched and marked easily. After the war, new soft, super-strong plastics invaded the high street and suburban home.

In shops, the paper bag gave way to polythene. Invented in the United States, this tough, translucent thermoplastic polymer of ethylene was developed to make lightweight and corrosion-free pipes, tubing and industrial textiles; it was also used widely in packaging.

By the mid-Sixties, new plastics were emerging at a bewildering rate and invading our lives; think of how many uses we make of new- fangled polypropylene - bottles, laminates, pipes, fibres for carpets. Think, too, of how we rely on polystyrene, in the form of rigid white foam, as a packaging material for everything from Christmas decorations to take-away burgers. In offices, most of us are reduced to drinking from polystyrene cups. Dominating so many of our desks are hefty plastic boxes faced with illuminated plastic screens: the computer is almost wholly made of plastics and has changed the way we live as radically as the car.

Curiously, the desktop computer remains one of the nastiest of all plastic artefacts. Not only does it lack a friendly or elegant form, but the plastics with which designers and manufacturers choose to shroud its workings are some of the most tasteless available. Computers are typically finished in grey or beige plastics, like pieces of medical equipment, and stain easily. Within weeks of hard use, a desk-top computer terminal looks as if it has been dragged through a hedge backwards. It seems odd that designers have yet to give them interesting shapes and likeable colours.

Again, the problem of plastic is that it is too easy to produce, too easy to give shape to and too easy to handle; as a result it is overused. Only gradually are architects and builders reducing their dependency on plastics. Plaster, for example, is making a comeback in offices (for walls and ceilings). Plastic has its purpose; it should not - for the sake of ecology as well as our sensibilities - be overused.

The furniture industry has made the most enjoyable use of plastic. Even here, however, designers and manufacturers have turned away from the material; the wilfully experimental designs of the Fifties and Sixties are now very much the stuff of auction rooms, design museums, flea markets and fashionable galleries.

Plastic gave designers like Eero Saarinen, Robin Day, Vico Magistretti and Joe Colombo unprecedented freedom in creating new forms. But there is little doubt that such pieces of furniture were not really made to last; they scuff, they scratch and they are difficult to keep clean. This might not matter if plastic aged well, but it rarely does. Where wood, stone and iron develop lovely patinas over time, worn plastic simply looks ugly. A wooden chair can be restored to pristine condition, but its plastic equivalent can only be returned to as-new condition by being melted down.

Plastic is often at its best as the backroom- boy of production materials; it does not make perfect furniture, interiors or fabrics, but it is a material (or group of related materials) that serves us well behind the scenes. Today, the most sophisticated developments in super- strong, super-light polymers - such as Du Pont's Kevlar - have been developed to be essentially out of sight. Kevlar, being expensive to process, is not wasted in the manufacture of cheap and cheerless consumer tat; it is uncoloured, uncelebrated and uncollected by devotees of plastic 'antiques'. But poke your nose underneath a 217mph Jaguar XJ220 and that drab, plastic material forming much of the underside of this dynamic car is Kevlar.

Plastic in all its forms is easy to deride. It may well be the stuff of roadside garbage, tacky toys, stained desktop computer terminals and exuberant Sixties furniture. Yet it also underpins most of the sophisticated structures and activities that we take for granted. Once we learn how to dispose of it properly, plastic will be seen as the friend its inventors have long assumed it to be.-

(Photograph omitted)