Nylon rapidly replaced silk in clothing and military applications during World War II. Despite legal wrangling over its true inventors, polypropylene rapidly becomes one of the most popular plastics. Due to its versatility, it is used in nearly all plastic applications.
Could anyone have foreseen how much these early innovative materials would transform our lives? And the innovations continue… Stay tuned for a more recent history of plastics. Do you have a question about plastic or the history of plastic? Submit your questions here! Section About Plastics. Professor Plastics Read Bio. Take a moment… Our cars seat cushions, air bags, bumpers, dashboards… Our fashion nylon, spandex, polyester, faux fur… Our homes carpeting, foam insulation, vinyl siding, composite decking… Our appliances televisions, coffee makers, alarm clocks, electric toothbrushes… Our sports football pads, bicycle helmets, surfboards, skis… Our health preemie incubators, bandages, hygienic medical packaging, syringes… Our food packaging tamper resistant film, takeout boxes, milk jugs, leftover containers… Shall I go on…?
Here are my favorite highlights from the early history of plastic: Parkesine The first man-made plastic, called Parkesine after its inventor Alexander Parkes, is revealed at the Great International Exhibition in London.
It bounces cheerfully back. When they came in, they were replacing things like pewter, which gets dented, and glass and ceramics, which have the terrible problem that they smash. Synthetic plastics had the added advantage that they seemingly lasted forever. No organisms had evolved that were capable of digesting these complicated and alien materials. But that advantage is, of course, also a great disadvantage. Plastic might sit in a landfill, or litter a street, for thousands of years without decomposing.
More worrying are reports that much of our plastic junk - including gazillions of tiny plastic micro-particles that might have broken off from plastic-based clothes in washing machines - have found their way into our oceans, where they collect in giant floating junkyards that go round and round in natural gyres in the ocean currents. There is some evidence that bacteria may be evolving to feed on this junk , exploiting the energy embodied in the polymers' hydrocarbon bonds. But there are surely better solutions - such as plastics designed to decompose.
Polylactic acid PLA for example, is derived from corn starch, the same stuff that corn flakes are largely composed of. Starch, like cellulose, is a polysaccharide - a long chain of sugar molecules fused together.
PLA can be used to make plastic bags, and fibres for clothing. Meanwhile, cellulose can be turned not only into celluloid, but also the food wrapper cellophane, or the fibre rayon. All of these polymers are compostable. Over months or years, they will be gradually broken down by microbes. Apart from the steady accumulation of plastic junk, there is another looming problem - where we get our plastics from in the first place. Currently, most of them come from oil and gas.
But when these finite sources eventually run out, the obvious solution will be to go back to the days of Parkes and Goodyear, and look to biology. Normally derived from crude oil, the stuff is now being produced from sugar cane by the Brazilian petrochemicals firm Braskem. It uses vats of yeast that have been genetically modified to turn the sugar into ethanol, which can then be converted by stages into ethylene, polythene and PET.
Such bioplastics also help battle climate change, Tomkinson argues, as the sugar cane draws carbon dioxide out of the atmosphere, sequestering it into a product that can be recycled like any other - even if it is ultimately burned to generate energy, and the carbon dioxide released back into the atmosphere.
But Tomkinson says that in the longer term, the main driver for the bioplastics renaissance will not be eco-friendly altruism, but the profit motive. The big chemicals companies realise that they need to find alternative feedstocks to replace crude oil, and this is already reflected in their research and development spending. For now, the oil price remains steady.
And, thanks to the shale revolution, American gas prices are exceptionally low, turning the US into a major producer of PVC. And that's where mankind's brief love affair with synthetic plastics will come to an end. Image source, Thinkstock. Polyethylene is the simplest example of a linear polymer. If the monomers not only form straight chains but also form long side chains off the main backbone, the resulting polymer is described as branched and may look like a tree branch or the stems of a bunch of grapes.
Another arrangement occurs when the long chains are chemically linked together, forming a mesh-like structure known as a crosslinked configuration. Vulcanized rubber, which is formed by reacting natural rubber isoprene with sulfur, is an example of a crosslinked polymer.
The polymer molecules can also have different arrangements. If the arrangement has no particular order or form, like the arrangement of spaghetti on a plate, the polymer is said to be amorphous having no shape. Amorphous polymers are often transparent and, therefore, are used as food wrap, headlights, and contact lenses. These materials also tend to have lower melting points.
If the arrangement is in a distinct pattern, the polymer is said to be crystalline. The higher the degree of crystallinity, the less light passes through. Such materials are either translucent or opaque. This quality depends on the degree of crystallization and the presence of additives. Crystalline polymers have greater strength and tend to have higher melting points. Polymers seem to have a limitless range of characteristics along with properties that allow them to be dyed in an endless array of colors.
Their properties can be enhanced by additives. Being able to design or engineer polymers for specific applications makes plastics unique materials. Although each polymer has unique characteristics, most polymers have some general properties:. The raw material for manufacturing plastic products is called a resin. These resins are often used in packaging.
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