On a molecular scale, there are surprising similarities between the outer shell of a golf ball and the white oil paint used by Van Gogh and his contemporaries. In both cases, the interactions between zinc ions and polymer ...
Polymers
Jun 24, 2019
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"How do you drink a milkshake without a straw?"
Environment
Jun 24, 2019
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Despite offering chairs and notebooks made from recycled paper at a Bangkok summit, Thailand and its Southeast Asian allies were accused Sunday of a "greenwash" with their oceans and communities brimming with plastic refuse.
Environment
Jun 24, 2019
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A study of whales and dolphins that have washed up dead in Greece over a 20-year period has found alarmingly high levels of plastic trash—mostly bags—in the animals' stomachs, which can condemn them to a slow and painful ...
Environment
Jun 21, 2019
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Protestors in Bangkok on Thursday dumped plastic waste in front of a government building and called on Southeast Asian leaders to ban imports of trash from developed countries.
Environment
Jun 21, 2019
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Greenpeace on Wednesday raised the alarm over microplastics in rivers after finding the pollutant in all the rivers it tested in Britain, calling it a "problem of enormous complexity".
Environment
Jun 19, 2019
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"Microbeads! A blue one—and a pink one!"
Environment
Jun 19, 2019
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Take a moment to imagine yourself on a sun-kissed beach on Koh Rong, watching the sea foam onto the white sand and hearing the gentle rustle of tropical rainforest behind you. The stunning beaches and vibrant marine biodiversity ...
Environment
Jun 18, 2019
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The big problem with plastics is that though they last for a very long time, most are thrown away after only one use. Since plastics were invented in the 1950s, about 8,300m metric tonnes (Mt) have been made, but over half ...
Materials Science
Jun 18, 2019
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24
It's the stuff everyone tries to get rid of but that never really goes away:
Environment
Jun 17, 2019
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A plastic material is any of a wide range of synthetic or semi-synthetic organic solids used in the manufacture of industrial products. Plastics are typically polymers of high molecular mass, and may contain other substances to improve performance and/or reduce production costs. Monomers of plastic are either natural or synthetic organic compounds.
The word plastic is derived from the Greek πλαστικός (plastikos) meaning capable of being shaped or molded, from πλαστός (plastos) meaning molded. It refers to their malleability, or plasticity during manufacture, that allows them to be cast, pressed, or extruded into a variety of shapes—such as films, fibers, plates, tubes, bottles, boxes, and much more.
The common word plastic should not be confused with the technical adjective plastic, which is applied to any material which undergoes a permanent change of shape (plastic deformation) when strained beyond a certain point. Aluminum which is stamped or forged, for instance, exhibits plasticity in this sense, but is not plastic in the common sense; in contrast, in their finished forms, some plastics will break before deforming and therefore are not plastic in the technical sense.
There are two types of plastics: thermoplastics and thermosetting polymers. Thermoplastics are the plastics that do not undergo chemical change in their composition when heated and can be moulded again and again; examples are polyethylene, polypropylene, polystyrene, polyvinyl chloride and polytetrafluoroethylene (PTFE). Thermosets can melt and take shape once; after they have solidified, they stay solid.
The raw materials needed to make most plastics come from petroleum and natural gas.
This text uses material from Wikipedia, licensed under CC BY-SA
