In it's pure form PVC is quite rigid and will not easily catch fire, so it forms the basis of all kinds of pipes, and coverings for such things as siding, windows and doors. When other things, called plasticizers, are added to PVC, the material becomes much more flexible and can be used to produce everything from garden hose to shower curtains.
Such a universal, and safe, material has a dangerous start. The monomer used in it's synthesis is a deadly poisonous gas called vinyl chloride. This gas is made by passing oxygen, hydrogen chloride and ethylene over copper, which acts as a catalyst.
After very careful storage and handling, the vinyl chloride is mixed with initiators that begin the polymerization process. PVC is a homopolymer, which in its pure form is too stiff for most applications.
However if a second momomer, vinyl acetate is also incorporated into the chain, a more flexible product is created that has many more uses.
In , the Union Carbide Corporation first began making this 'copolymer', called it "Vinylite", and pressed music into it to make phonograph records. Carbon and Natural Bio-Polymers. The carbon atom has six electrons, four in the outermost energy level. Unlike natural polymers, which are found in nature, synthetic polymers are made by humans. They are derived from petroleum oil and include products such as nylon, synthetic rubbers, polyester, Teflon, polyethylene, and epoxy. Synthetic polymers have a number of uses and are widely used in household products.
These products include bottles, pipes, plastic containers, insulated wires, clothing, toys, and non-stick pans. Actively scan device characteristics for identification.
Use precise geolocation data. Select personalised content. Create a personalised content profile. Measure ad performance. Select basic ads. Create a personalised ads profile. Select personalised ads.
Apply market research to generate audience insights. Measure content performance. Now take a look in the mirror. Many proteins in your body are polymers, too. Consider keratin KAIR-uh-tin , the stuff your hair and nails are made from. Even the DNA in your cells is a polymer.
By definition, polymers are large molecules made by bonding chemically linking a series of building blocks. Think of a polymer as a chain, with each of its links a monomer. Those monomers can be simple — just an atom or two or three — or they might be complicated ring-shaped structures containing a dozen or more atoms.
But in proteins, DNA and other natural polymers, links in the chain often differ from their neighbors. In some cases, polymers form branching networks rather than single chains. Regardless of their shape, the molecules are very big. They are so big, in fact, that scientists classify them as macromolecules. Polymer chains can include hundreds of thousands of atoms — even millions.
The longer a polymer chain, the heavier it will be. And, in general, longer polymers will give the materials made from them a higher melting and boiling temperature. Also, the longer a polymer chain, the higher its viscosity or resistance to flow as a liquid. The reason: They have a greater surface area, which makes them want to stick to neighboring molecules.
Polymers are used all across chemistry and materials science. A polymer is a molecule made up of repeating units. It might have branches, or it might just be one straight line of molecules, each connected in the same way. Polymers can range in simplicity from polyethylene, which has monomers of one carbon atom connected to two hydrogen atoms, all the way through to more complex proteins polypeptides , which are chains of various amino acids.
These chains can become extraordinary structures, like antibodies and enzymes. And slight variations in a polymer can have big effects. Polymers are everywhere, both synthetic and naturally occurring. Here are a few polymers you interact with on a daily basis. All plastics are polymers of one form or another. The long molecular chains of polymers can make them resistant to water and very difficult to break down — which are exactly the properties that make plastics so useful, and so damaging to the environment.
In Australia, plastic is classified in seven ways : six of them correspond to a specific polymer. For instance, category 1 is polyethylene terephthalate, or PET, which is made of monomers of ethylene terephthalate. All other types of plastic polymer fall into category 7: other.
The recyclability of the different types of plastic depends on your local council.
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