- Amorphous Density: 0.85 g/cm3 
- Crystalline Density: 0.95 g/cm3 
- Melting Point of 320°F (160°C)
- Doesn’t Soak up water (good for uses around moisture)
- Very strong against corrosion; doesn’t react with chemicals like alkaline substances, acids, etc.
- Low flammability
- Poor UV resistance
- Polypropylene contains a carbon backbone with only Carbon to Carbon Bonds and Carbon to Hydrogen bonds
- The bonds look like the following:
- Contains methyl groups as well (CH3)
Chemical Production Process
- Tin Chloride (TiCl3) acts as a catalyst and is added to a hydrocarbon solvent
- Propylene is polymerized. Pressure is 10 kgf/cm and the temperature is between 60°C and 80°C.
- The catalyst is broken down using methanol and the polymer is washed. Polypropylene is then separated from the solvent
- food packaging,
- reusable containers (high m.p. allows them to go in the dishwasher)
- thermal pants and shirts made for the military
- laboratory equipment,
- automotive components
History of Polypropylene
- Was discovered by Paul Hogan and Robert L. Banks in 1951
- In an attempt to make dimers and trimers of ethylene and propylene (with a chromium oxide catalyst) for gasoline use, they accidentally produced some crystalline polypropylene and linear polypropylene
- Process was patented by Phillips Petroleum at the beginning of 1953
Environmental Implications of Polypropylene
Polypropylene is a polymer that can be both used as a structural fabric and as a fibre. Because polypropylene has the ability to be broken down in the environment easily, scientists have discovered a way to create an environmentally friendly plastic bag. This plastic product is known as a non woven polypropylene. These bags are accepted by recycling plants and centres because they are easily broken down, and are very cheap to manufacture. These bags are being shipped to grocery stores, where most of our plastic bags are found. The physical properties of PP allow it to be strong enough to be used as a daily shopping bag.
This non woven polypropylene is helping to encourage and promote a clean environment for us to live in, and shows that there are multi-purpose alternative to the highly polluting plastic bags we’re all come accustomed to.
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Lim, H. (2009, December 30). Using Non Woven Polypropylene For an Environment Friendly Bag. EzineArticles Submission – Submit Your Best Quality Original Articles For Massive Exposure, Ezine Publishers Get 25 Free Article Reprints. Retrieved April 5, 2010, from http://beta.ezinearticles.com/?Using-Non-Woven-Polypropylene-For-an-Environment-Friendly-Bag&id=3487487
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 Amorphous density means to have no defined shape, or an easily altered shape; this means that polypropylene would be a liquid for this density to be measured
 Crystalline density occurs when the polymer has a regular, defined pattern, which would occur when polypropylene is