Some ubiquitous 'mers' are ethylene, styrene and acrylamide. Each of these may be polymerized to make,respectively, polyethylene (the soft clear plastic that plastic bags are made of), polystyrene (the stiffer,usually white plastic that the covers for soft-drink cups are made of), and polyacrylamide (the very tough,clear plastic that compact discs are made from). Look on the bottom of a recyclable plastic bottle-chances are you will see a PE or PS which means  polyethylene or polystyrene. These materials are examples of what happens to polymers when they  solidify: the chains are entangled and packed together to make light, tough, flexible materials.
A way to think about some of these materials is to think of what a big glob of cooked spaghetti is like. If  you stretch it a bit, it is kind of elastic, but if you really pull hard, the noodles start to slide past one  another and the whole glob starts to permanently deform. At least that is the idea! Does this remind you of  what happens to a PE plastic bag when you stretch it? Think about what must be happening to the microscopic spaghetti that the bag is made up of! This way of thinking doesn't work very well to describe stiffer plastics like PS: the chemical units in stiffer  plastics are actually packed together in a orderly way, into pseudo-crystals. If you heat up PE or PS to moderate temperatures, if the chains have not been chemically stuck together('cross-linked') they will melt, and turn into goopy liquids, which are called polymer melts. Some polymers   are melts even at room   temperature,like poly dimethyl siloxane (PDMS), or poly(ethylene-propylene)  (PEP).
Remembering that paper is made of cellulose, which is a polymer of biological origin, if you look around   the room that you are in, you will see that a good fraction of the stuff in it is made of polymers. And of  course, you are, too!Lantz Lenses, A manufacturer of eyeglass lenses in St. Cloud, Minnesota, Lantz Lenses used acetone to remove abrasive pads from lens-grinding tools. In 1993, Lantz Lenses purchased 1,050 pounds of acetone and generated approximately 2,300 pounds of acetone contaminated waste and 920 pounds of acetone emissions. After examining their process, Lantz Lenses determined that the abrasive pads could be removed by manual scraping alone (at no increased labor cost), eliminating the need for acetone altogether and saving hundreds of dollars per year. Co-inertia analysis was used on to the two data sets described in the Data Sets. The data were arranged in two tables, one with 20 rows (amino-acids) and 402 columns (physico-chemical and biological properties), and the second with 20 rows and 999 columns (E. coli proteins).



 
 
 

 
 
