Polyurethanes

1. Polyurethanes

2. History of Polyurethanes: Polyurethane Chemists • Dr. Otto Von Bayer (1937) • IG Farben Industries • Rigid and flexible foams • TDI and polyols • Attempts to reduce natural rubber use

3. History of Polyurethanes:Polyurethane Chemists • Adolf Wurtz (1848) • Karl-Heinz Hentschel (1884) • Phosgenation of amines

4. Isocyanate Monomer Synthesis • Dr. Otto Bayer (1937) • First diisocyante synthesis • Toluene Diisocyanate Synthesis (TDI) • Reaction creates 80/20 mixture of 2,4-TDI and 2,6-TDI

5. Isocyanate Monomer Synthesis • DiphenylmethaneDiisocyanate (MDI) Synthesis • Attempt to find less toxic monomer for PU reactions • MDI chemistry is more complex • Allows for more specific applications

6. Imperial Chemical Industries • ICI and WWII applications of isocyanates • Barrage balloons • Used MDI as cross-linking agent • Resistant to hydrogen • Applications also included rigid foams in planes • War applications soon faded • Isocyanates and water • Carbon dioxide is side product • Initially a defect it was turned into an application as foam • ICI takes notes from Bayer AG • Designs a machine outside of the Germans patented machine

7. Imperial Chemical Industries • Toxicity of TDI (1950s) • Led to design of MDI/polyester systems • Portable refrigerators, domestic chambers of ships, chemical plan insulation • Further improvements with CFC’s • CFC blowing agents created superior insulating foams • Thin walled refrigerators create interest rigid PU foams around the world

8. Polyurethanes • Polyurethanes are much more than just foam • PU’s can be • Elastomers • Paints • Adhesives • Fibers • Spandex

9. Breakdown of the PU Industry Figure from Essentials Chemical Industry on University of York website

10. Economics • The PU industry was estimated to produce 13.65 million tons of plastic in 2010 and is expected to grow to 17.95 million tons by 2016 • The PU industry is expected to grow from $33 billion in 2010 to $55.5 billion in 2016 • North America, Asia-Pacific, and Europe account for 95% of the PU market Numbers found from source 6

11. Polyurethane Structure Carbamate bonds created by isocyanates reacting with hydroxy groups of a polyol

12. Polyurethane Reactions • Tertiary amines catalyze the reactions • Isocyanate groups react with polyols

13. Polyurethane Monomers • Polyurethanes consist of different block co-polymers • MDI- 4 4'-diphenylmethane diisocyanate • TDI- Toluene-2,4-diisocyanate

14. Polyurethane Monomers Polyols- hydroxy terminated polyether, polyester, polyolefins, and glycols

15. Polyurethane: Block Copolymers • Soft block/hard block microphases -Poly(1,4-butylene adipate) is part of the soft block microphase -Soft blocks have 600-3000 MW and Tg below room temperature -The soft block cross-link interaction with the hard block gives rise to the rubbery nature of these elastomers -The hard block consists of TDI or MDI -Higher density of phenyl rings and urethane links cause hardness

16. Soft/Hard Block H-Bonding Interactions Figures from source 7

17. Importance of Polyol choice Figures from source 7

18. Polyurethane Reactions • Multiple types of reactions make up different end products of polyurethanes • Polyurea reactions are important for spandex production

19. Which sometimes can be a bad thing! • Someone needs to introduce this guy to pants and suspenders! • Suspenders are made of polyesters • Dr. Tisko should tell this guy how awesome suspenders are

20. Bibliography • http://www.pslc.ws/macrog/urethane.htm • http://www.8linx.com/cnc/polyurethane_foam.htm • http://www.essentialchemicalindustry.org/polymers/polyurethane.html • http://sunilbhangale.tripod.com/pu.html • http://www.poliuretanos.com.br/Ingles/Chapter1/132comercial.htm • http://www.plastemart.com/Plastic-Technical-Article.asp?LiteratureID=1674&Paper=global-polyurethane-market-PU-foams-thermoplastic-elastomers • J.M. Buist. Developments In Polyurethane-1; Applied Science Publishers LTD, UK, 1978.