Plastic is obviously and important substance in our lives. Many different packages contain plastic or a mix of plastic and other materials. Many products we use also are made partly or entirely out of plastics. Of course, there are many different types of plastic and each has different uses and capabilities.
In general, a plastic is a mix of organic solids that can be molded into a specific shape. The solids might be entirely synthetic or perhaps a blend of synthetic and naturally occurring or semi-synthetic polymers. The majority of plastics are created out of synthetic polymers extracted from petrochemicals.
Plastics can be classified in several different ways and that would include the polymerization process that is used to create each kind of plastic, the processibility of each one of these different types of plastics also is a factor. In addition, scientists classify plastics by their general chemistry. When it comes to processibility, there are two categories to consider and these are known as thermoplastic and thermoset plastic.
These plastics have the word thermo in both of them which means that heat is applied to transform these plastics into products or packages. With a thermoplastic, the plastic item can be recycled, melted down and molded into a new product again and again. For the thermoset plastics though this is not the case because when these plastics are heated they undergo a chemical change which means they can't be melted down or reused. Even though plastics are technically not able to be melted down reformed, some can be used again for other purposes. To produce asphalt, vulcanized rubber which is used for tires is shredded and that is used to produce that.
Beyond those two basic classifications, plastics are furthered classified by their physical properties, which might include factors such as density, resistance to chemicals, glass transition temperature and tensile strength. The latter of which is the maximum amount of stress that the plastic can withstand when you are stretching it without breaking. The glass transition temperature is basically the temperature at which a substance moves from a hard state into a molten state, where it can be molded.
The overall strength is what we call the density although technically this means the mass per unit volume. A good example would be polypropylene, which is used to make products like yogurt cups. Acrylonitrile butadiene styrene has a higher density than this and it is used to create products like LEGO bricks, some auto parts and a few musical instruments.
Another classification mentioned above was resistance to chemicals and this can be highly important. Consider for a moment that bottle of bleach that you keep by your washing machine. It is contained in a type of thermoplastic that is highly resistant to chemicals. In this case, the plastic is resistant to the bleach; otherwise, the bleach could leech through the plastic. While bleach is a helpful product, it also can burn the skin and eyes and is a poison so it needs to be contained safely. Other items don't need to be this resistant to chemicals, such as your yogurt cup or the container that holds blueberries.
In general, a plastic is a mix of organic solids that can be molded into a specific shape. The solids might be entirely synthetic or perhaps a blend of synthetic and naturally occurring or semi-synthetic polymers. The majority of plastics are created out of synthetic polymers extracted from petrochemicals.
Plastics can be classified in several different ways and that would include the polymerization process that is used to create each kind of plastic, the processibility of each one of these different types of plastics also is a factor. In addition, scientists classify plastics by their general chemistry. When it comes to processibility, there are two categories to consider and these are known as thermoplastic and thermoset plastic.
These plastics have the word thermo in both of them which means that heat is applied to transform these plastics into products or packages. With a thermoplastic, the plastic item can be recycled, melted down and molded into a new product again and again. For the thermoset plastics though this is not the case because when these plastics are heated they undergo a chemical change which means they can't be melted down or reused. Even though plastics are technically not able to be melted down reformed, some can be used again for other purposes. To produce asphalt, vulcanized rubber which is used for tires is shredded and that is used to produce that.
Beyond those two basic classifications, plastics are furthered classified by their physical properties, which might include factors such as density, resistance to chemicals, glass transition temperature and tensile strength. The latter of which is the maximum amount of stress that the plastic can withstand when you are stretching it without breaking. The glass transition temperature is basically the temperature at which a substance moves from a hard state into a molten state, where it can be molded.
The overall strength is what we call the density although technically this means the mass per unit volume. A good example would be polypropylene, which is used to make products like yogurt cups. Acrylonitrile butadiene styrene has a higher density than this and it is used to create products like LEGO bricks, some auto parts and a few musical instruments.
Another classification mentioned above was resistance to chemicals and this can be highly important. Consider for a moment that bottle of bleach that you keep by your washing machine. It is contained in a type of thermoplastic that is highly resistant to chemicals. In this case, the plastic is resistant to the bleach; otherwise, the bleach could leech through the plastic. While bleach is a helpful product, it also can burn the skin and eyes and is a poison so it needs to be contained safely. Other items don't need to be this resistant to chemicals, such as your yogurt cup or the container that holds blueberries.
About the Author:
Lenna Stockwell likes blogging about how stuff is made. For further information about plastic thermoforming or to discover more about retail product packaging solutions, please go to the Indepak.com site now.
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