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Gluep & Oobleck

Gluep & Oobleck. Polymers Monomers Gluep Oobleck Viscosity Newtonian v. non-Newtonian Natural Polymers Plastics. Polymers. A large, complex molecule built from smaller molecules (monomers) joined together Form from carbon bonded to one another and to other kinds of atoms. Monomers.

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Gluep & Oobleck

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  1. Gluep & Oobleck Polymers Monomers Gluep Oobleck Viscosity Newtonian v. non-Newtonian Natural Polymers Plastics

  2. Polymers • A large, complex molecule built from smaller molecules (monomers) joined together • Form from carbon bonded to one another and to other kinds of atoms

  3. Monomers • Small molecules, that can join with other similar molecules to form very large molecules, or polymers. • The chain of molecules can be of different lengths • All monomers are able to form chemical bonds to at least two other monomer molecules.

  4. a polymer consisting of all the same monomer a polymer consisting of more than one type of monomer Polymers

  5. GLUEP (SILLY PUTTY) • silicone polymer • a non-Newtonian fluid • forms thin strands when pulled apart slowly • will break when pulled apart quickly • increased viscosity under stress (pressure) LIQUID

  6. LIQUID OOBLECK • Colloidal Suspension • Cornstarch is made of polymers. • non-Newtonian fluid • Pressing on the cornstarch suspension squeezes the water from between the particles. • It resists flow because the particles are now grinding against each other. • Releasing the pressure allows the water to seep between the particles again and the suspension flows more easily • Increased viscosity under pressure (the fluid becomes stiff) • Wet sand - The sand hardens under your feet. But if you lean over and draw a line in the sand with your finger, you see that it's rather soft.

  7. VISCOSITY • Viscosity – a measure of a fluids resistance to flow • Picture a flowing liquid as a series of layers of liquid sliding past each other. • The resistance to flow is because of friction between these layers. • High viscosity – slow flow • Low viscosity – quick flow

  8. Newtonian v. non-Newtonian • Newtonian fluid – • If you want one layer to slide over another twice as fast as before, you'll have to overcome a resisting force that's twice as great • Gases, cooking oil and water are common examples. • These fluids become more viscous (higher viscosity) when they cool. This means that their resistance to flowing increases. • non-Newtonian fluid. • Their viscosity increases not with temperature, but when the liquid is stirred or compressed. • Colloidal suspensions and polymer solutions like ketchup, yogurt, gravy and starch/water paste are examples. • They're non-Newtonian fluids because doubling the speed that the layers slide past each other does not double the resisting force. It may less than double (Shear Thinning like ketchup), or it may more than double (Shear Thickening as in the case of quicksand and gravy). That's why stirring gravy thickens it, and why struggling in quicksand will make it even harder to escape.

  9. Natural Polymers • Plant Polymers – • CELLULOSE – long fibers made in plants when sugar molecules are joined into long strands • Cotton balls • Cotton cloth • Paper • Animal Polymers – • SILK • WOOL • PROTEINS – amino acids (monomers) combine to form proteins • Properties of protein depend on which amino acids are used in what order • FINGERNAILS • HAIR • HEMOGLOBIN

  10. PLASTICS (Synthetic Polymers)

  11. Polyethylene Terepthalate PET • Invented by J.R. Whinfield and J.T. Dickson, 1940. • Uses: clothing, plastic films, plastic bottles CH2 = methylethylene

  12. High-Density Polyethylene • Invented by Robert L. Banks and J. Paul Hogan, 1951. • Uses: milk jugs, shampoo bottles, motor oil bottles, high-strength fibers

  13. PVC (Polyvinyl Chloride) • Invented by Waldo Semon, 1926. • Uses: water pipes, swimming pool liners, shower curtains, house siding, garden hose, LP records, vinyl car tops

  14. Low-Density Polyethylene • Invented by Eric Fawcett and Reginald Gibson, 1935, in England. • They were trying to make an explosive gas (ethylene) react with a much larger molecule (benzaldehyde), by forcing them together under high pressure. What they got was a useless, (so they thought!), white, waxy solid that couldn't be used for anything interesting or practical. • Nothing much more was done with this "polyethylene" until the start of the Second World War. • Uses: garbage bags, disposable diapers, plastic films

  15. Polypropylene • Invented by Robert L. Banks and J. Paul Hogan, 1951. • Uses: bags for snack foods, plastic buckets, fibers for rope, indoor-outdoor carpeting

  16. Polystyrene • Invented by Eduard Simon, 1839. • Uses: plastic foam packing materials, hot drink cups, plastic disposable utensils, rigid plastics of all kinds

  17. Other • anything else, including items madefrom more than one kind of polymer

  18. Links • http://www.brooklyn.cuny.edu/bc/ahp/LAD/C3a/C3a_polymers.html • http://www.chemheritage.org/EducationalServices/faces/poly/readings/rec.htm

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