Who are you?

1. Who are you?

2. Why are we here?

3. Define molecule. Na5333333888Cl5333333888 ??? C2H4 ??? m(C2H4)   [C2H4 ]m ???

4. Why big?

5. PE Images: a railcar full of PE leaves a small Louisiana plant about every hour. We have many plants. The ExxonMobil plant just north of the Baton Rouge airport makes the PE for 40% of all milk cartons in the US.

6. Dow is one of Louisiana’s largest producers. $550 million purchased from Louisiana companies $340 million payroll $58 million state & local taxes $1.8 million donations Tons of polyethylene Methocel Image: http://www.unitedwaysb.org/Ice%20Cream.jpg

7. The DNA to copy a lungfish has a molecular weight of 69,000,000,000,000 g/mol. What’s that in tons per mole? Do it without your calculator! DNA Image: http://www.biology.lsu.edu/bmb/images/dna.jpg

8. History belongs to the victors.(this history from Elias’ book, Megamolecules) ~1300 BC Egyptian mummification reaches its zenith. (First mummy is from approx. 5000 B.C.???)

9. 1839* "Styrax liquidus" (a resin used by the Egyptians as embalming fluid, isolated from a tree) produces a clear liquid, "styrol", when distilled. Styrol solidifies when heated.  Everyone knows that pure substances melt sharply on heating.  Melting points are a classic way organic chemists use to ascertain purity.  Stuff that doesn't melt on heating can't be very pure.  Why bother with gunk?  It is assumed that the gunk is oxide of styrol, called "styrene oxide". *First photograph of the moon taken.

10. ~1845* It is learned that the gunk contains no oxygen atoms and, in fact, has the same empirical formula before and after solidifying (actual formula is under debate since relative masses of C and H are not known at this time). Name is changed to metastyrene. "Polymerization" coined as a word meaning that many parts had joined without changing. *Texas annexed to U.S.Mexican-American warTexas becomes a state

11. The great debate! Right then and there, the argument began: Chemistry often involves change, so…. Could polymerization just be simple, physical aggregation?

12. Other chemicals also “polymerize”. Ethylene oxide also polymerizes this way (no change of formula) Graham (of effusion law fame?) notes that diffusion of crystalline substances dispersed in solutions is fast, while that of noncrystalline substances is slow.  Polymers diffuse slowly, hence probably not crystalline, hence probably not pure.  Again, why measure gunk? 

13. ~1888 to ~1925 Thermodynamic methods are applied to polymers, basically by adapting the ideal gas law to solutions.  It is found that the polymers have enormous masses--e.g., tens of thousands.  But the doubters again raised objections:  • poor reproducibility, even within the same research group • answers depended a lot on concentration and method • chemical methods for crystallizable compounds did not have these problems--maybe thermodynamics doesn't work if you try to measure GUNK! (Or maybe a new thermodynamics needs to be developed—how exciting!)

14. About 1910, we find this lovely example of scientific method. On the other hand....rubber is thought to be two units of isoprene joined in a circle.   The high viscosity is attributed to secondary forces grouping the circles into great aggregates.  If so, then brominating the isoprene should dramatically alter the viscosity.  It did not.  Is there a theory here? Is there a scientific law here? http://www.iisrp.com/WebPolymers/11POLYISOPRENE.pdf

15. In the early 1900’s people were still debating. • Some people were still people not convinced...because where are the end groups if the chains are linear?  • No one could find them, and no one could admit such a failure of chemical analysis...so linear polymerization was a mystery.  Maybe polymers were large rings??? • Leaping ahead for awhile… • In fact, it was a failure of chemical analysis that the end groups were not found.  On a polystyrene of M=104,000 there are only 2 ends:  Only 1 in 500 styrene units is different.  Even today, end groups are hard to see. • In fact, you can make cyclic chains, too! Robert Grubbs, Cal Tech Nobel Prize Chemistry, 2005 http://pubs.acs.org/cen/topstory/8038/8038notw8.html http://www.rsc.org/images/FEATURE-Nobel-Grubbs_tcm18-40660.jpg

16. 1920’s onward Staudinger had the good luck to be poor. He could only afford a simple experiment that proved to be very precise: viscosimetry. He found that the viscosity increment per unit polymer did not go away. Stein’s law: the product of money and intelligence is a constant. Staudinger Nobel 1953 If secondary, physical forces hold  polymers together, they should eventually go away if we continually dilute the polymer solution and polymers would fall apart. They did not. Richard Stein

17. Alternate history: do better “polymers” and more dollars make better history? Diagram from Svedberg’s Nobel Prize Lecture, showing the oil and hydrogen (yes, hydrogen!) circulation system for one of his AUC’s Theo Svedberg Nobel 1926 Images from Nobel prize website

18. At LSU…. One of the best academic polymer research programs in the U.S. Rich history of successes. Polymeric “gunk” and elegant biological macromolecules peacefully coexist…as do those who research them…as will you in this class and its follow-on (Chem 4011). The LSU macromolecular program is rather more biological than most, yet there are new hires on the “gunk side” and these result in exciting new materials science opportunities in interdisciplinary research. Your gateway to nanotechnology. What’s the difference between polymer science & nanotechnology?

19. Who are youTechnically?

20. Graveyard—old slides, slides we may or may not use, etc. below this point.

21. Macromolecular Jargon The objective of MS I & II is you know these terms (and more!), the theory behind them, and how to apply them. Random coil, Persistence length, Polydispersity index, Radius of gyration, Hydrodynamic radius, Free-draining, Lattice theory, Partial specific volume, Binodal, Spinodal, Kramers-Kronig relationship, Reaction injection molding, Reactivity ratio, Time-temperature superposition, Fractal, ATRP, Storage and Loss Modulus, Free volume, Glass, Disproportionation

22. Why do we need big molecules Engineers: why molecules at all? Chemists: why large ones?

23. A sordid history I tell you, with my doctor, I don't get no respect.  Well, I told him I've swallowed a bottle of sleeping pills.  He told me to have a few drinks and get some rest. I went to see my doctor... Doctor Vidi-boom-ba. Yeah...I told him once, "Doctor, every morning when I get up and look in the mirror I feel like throwing up.  What's wrong with me?  He said, "I don't know, but your eyesight is perfect." Rodney Dangerfield: “I tell you—I get no respect.” More at: http://joecasaletto.com/jokes/rodney.htm

24. Whirlwind tour of the early history of polymers, from Elias’ book MegaMolecules • Styrax liquidus" (a resin used by the Egyptians as embalming fluid, isolated from a tree) produces a clear liquid, "styrol", when distilled ~1839.  • Styrol solidifies when heated.  Everyone knows that pure substances melt sharply on heating.  Melting points are a classic way organic chemists use to ascertain purity.  Stuff that doesn't melt on heating can't be very pure.  Why bother with gunk?  • It is assumed that the gunk is oxide of styrol, called "styrene oxide". • It is learned (~1845) that the gunk contains no oxygen atoms and, in fact, has the same empirical formula before and after solidifying (actual formula is under debate since relative masses of C and H are not known at this time).  • Name is changed to metastyrene. • "Polymerization" coined as a word meaning that many parts had joined without changing. • Right then and there, the argument had to begin--chemistry often involves change, so polymerization must be just aggregation—merely a physical association, not real chemistry. • Ethylene oxide also polymerizes this way (no change of formula) • Graham (of effusion law fame?) notes that diffusion of crystalline substances dispersed in solutions, while that of noncrystalline substances is slow.  Polymers diffuse slowly, hence probably not crystalline, hence probably not pure.  Again, why measure gunk? 

25. Early history, continued. • From ~1888 to ~1925 thermodynamic methods are applied to polymers, basically the ideal gas law for solutions.  It is found that the polymers have enormous masses--e.g., tens of thousands.  But the doubters again raised objections:  • poor reproducibility, even within the same group • answers depend a lot on concentration and method • chemical methods for the crystallizable compounds didn't have these problems--maybe thermodynamics doesn't work? • On the other hand....rubber is thought (~1910) to be two isoprene units (-CH2-C(CH3)=CH-CH2-) joined in a circle.   The high viscosity is attributed to secondary forces grouping the circles into great aggregates.  If so, then brominating the isoprene should dramatically alter the viscosity.  It did not.  • Still people were not convinced...because where are the end groups if the chains are really linear?  • No one could find them, and no one could admit such a failure of chemical analysis...so linear polymerization was a mystery.  Maybe polymers were large rings??? • (Leaping ahead for awhile:  In fact, it was a failure of chemical analysis that the end groups were not found.  On a polystyrene of M=104,000 there are only 2 ends:  Only 1 in 500 styrene units is different.  Even today, end groups are hard to see. )

26. Hermann Staudinger (Nobel Prize, 1953 for work done in the 20’s & 30’s) If secondary, physical forces hold  polymers together, they should eventually go away if we continually dilute the polymer solution.  In a few lectures, we will start to tell you how Staudinger proved his hypothesis with classic simplicity. And, we will admit that others had much to do with it from the biological side. For now, please accept that he was right about very large, covalent structures. Let’s look at a few examples and start working on that jargon.

27. Oreos…but when Dupont expansion http://www2.dupont.com/Phoenix_Heritage/en_US/landing_era4.html Let an ultraintelligent machine be defined as a machine that can far surpass all the intellectual activities of any man however clever. Since the design of machines is one of these intellectual activities, an ultraintelligent machine could design even better machines; there would then unquestionably be an "intelligence explosion," and the intelligence of man would be left far behind. Thus the first ultraintelligent machine is the last invention that man need ever make. Mathematician I.J. Good--1965Read more: http://www.time.com/time/magazine/article/0,9171,2048299,00.html#ixzz24CSUoTvF Your world is different http://www.nbcnews.com/technology/futureoftech/17-year-old-girl-builds-artificial-brain-detect-breast-cancer-908308 Challenge the status quo The singularity: http://www.time.com/time/magazine/article/0,9171,2048299-2,00.html

28. Oreos and milk What’s polymeric? The crisco? The sugar? The milk? The re-sealable package? The milk carton? The glasses? Packaging blog: http://chowhound.chow.com/topics/726434