Chemistry of Organic Polymers and Recycling. Taz Choudhury Chem 481 March 2 nd , 2006. Organic Polymers. A macromolecule which is made of structurally similar monomers repeatedly connected by covalent bonds. Three main groups of polymers-
March 2nd, 2006
A macromolecule which is made of structurally similar monomers repeatedly connected by covalent bonds.
Three main groups of polymers-
Chemically inert; not attached by air or its pollutants
Very stable towards water
Step 2- Initiation
Step 3- Repeat
Step 2- ester intermediate
Step 1- Transesterification
Step 3- formation of ethyl terephthalate
After the bis(2-hydroxyethyl)terepthalate is formed, it continues with more transesterifications until the product gets bigger and bigger. When the molecular weight is large enough, it turns into poly(ethylene terephalate or PET. POLYESTER!!
Step 3- formation of bis(2-hydroxyethyl) terephthalate
Melting point- does not occur over a sharp temperature range because of its size.
Boiling Point- Polymers never boil
Solubility- Most polymers are insoluble in water; some are soluble only with strong organic solvents
Classified according to their polymer backbone (polyvinyl chloride, polyethylene, silicone)
Since they are partially crystalline and partially amorphous in molecular structure, they have a melting point
Plastics take many forms to be useful in our everyday life
The remarkable versatility and usefulness of plastic comes with a very high price.
They are durable and degrade very slowly
Burning plastics releases toxic fumes in the air that are harmful to humans, plants and animals
The large amounts of chemicals used to produce and dispose of plastic materials require the use of our already limited supply of fossil fuels.
Despite all the problems plastic has posed on our society today, THERE IS GOOD NEWS…
Recycling plastic products is a easy and effective solution to the problem
Thermoplastics products can be remelted and reused and thermoset plastics can be ground up and used as fillers.
Problems with recycling plastics
Automation of sorting of plastic waste
Unlike metal, a lot of plastics have to be manually sorted (movie)
Recycling certain types of plastic is unprofitable
Q: What percentage of plastics are recycled in the US every year?
“Product Stewardship Program”
Produce DeskJet printers from recyclable plastics.
Diverts as much as six million pounds of plastics from landfills by only using 25% recyclable plastic!