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Synthesis and Structural Characterization of Novel Epoxy Materials From Sucrose and Cotton. Navzer D. Sachinvala,* 1 Alexander A. Lambert III, 1 Nicolette Prevost, 1 Karol Maskos, 2 and Walter P. Niemczura 3 1 Cotton Chemistry and Utilization Research Unit,
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Synthesis and Structural Characterization of Novel Epoxy Materials From Sucrose and Cotton Navzer D. Sachinvala,*1 Alexander A. Lambert III,1 Nicolette Prevost,1 Karol Maskos,2 and Walter P. Niemczura3 1Cotton Chemistry and Utilization Research Unit, Southern Regional Research Center, USDA-ARS, New Orleans, LA; 2Coordinated Instrument Facility, Tulane University, New Orleans, LA; 3Department of Chemistry,University of Hawaii at Manoa, Honolulu, HI
This Talk is Dedicated to Professors Shelby F. Thames & Morton H. Litt For teaching me how to chemo-rationally transform agriculturally derived starting materials into industrial polymeric products
Why Develop New ProductsFrom Cotton & Sugar? • Emerge with better products • Diversify the markets in which these commodities do business • Stimulate economic opportunities in Rural America • Effect a return on investment
Consider Some Sugar Data • Production (US, M-STRV) 1995 and 2000: 7.390 and 8.903 • Raw sugar value (per lb. US $) 1995 and 2000 $0.290 and 0.190, current <$0.17 • 2003 average production cost estimate per lb. For raw sugar in Louisiana: ~ $0.155 • Number of sugar mills in Louisiana: 1900 ~400; 1950 ~50; 2004 ~16
Consider Some Cotton Data • US Market share for all cellulose fibers: 1970 = 43% of total fibers consumed; 2000 = 8% (Chem. & Eng. News, 5-15-00, p.25) • Formulators avoid using cotton in composites citing incompatibility with metals and plastics (Polymer Mater. Enc., 1996, Vol. C, Wiley, 1079)
Why Epoxies? • Annual Use in US > 0.6 B.lb. • Cost of Epoxies range from: $2.10 to 40.00 per lb., depending on use • Compound annual rate of growth in epoxies ~ 2 to 6 %, depending on use • Current suppliers: Shell, GE, Lord, 3M, HB-Fuller, Ciba, Am.Cyanamid, Dexter, and Hardman, Inc.
Building Materials Markets • 1997 Total Value of Shipments = $17.8 billion • Value added = $7.3 billion • Rate of growth (1992 to 2003) ~3 % per annum • Value of imports = $12.2 billion • Value of exports = $ 3.6 billion
Sucrose and Cellulose Sucrose is a dimer comprising glucose and fructose Cellulose (cotton) is a b-D-anhydroglucose polymer sucrose cellulose
New Products From Sucrose 42 pieces of intellectual property
% Remaining Wt. At 200C V/S Time Degradation studies were done in air. 4 Sample average / plotted value.
Proposed Mechanisms for Thermal Stabilization of PMMAs Thermal stability of PMMAs at 200 C in air was seen with fully substituted carbohydrate-based ethers only, & not with esters
Reactions of Epoxies With Diethylenetriamine (DETA) Curing and Thermoset Properties DETA = diethylene triamine; H theoretical 119.19kJ/mol epoxy
Dynamic Mechanical Analysis 3Pt Bending: DMA-7e Perkin Elmer; rectangular strips l x w x thickness = 20 x 7 x 1.5 mm; -150 to +200C; heating rate = 5 C/min; displacement amplitude 10m; = 3Hz; Static F= 110% (110mN; Dynamic F = 100mN)
Dynamic Mechanical Analysis Continued • KEY: • = EAS • = EMS • = ECS • = DGEBA
Reactions of Epoxies With PhenylalanineCuring and Thermoset Properties -PAA is Phenylalanine, TrOA is Trioctylamine
Reactions of Epoxies With AnhydridesCuring and Thermoset Properties -MNDA is Methyl-5-Norborene-2,3-Dicarboxylate, TrOA is Trioctylamine
EAS 3.2 Quantitative 13C NMR • Proton decoupler started just before the Rf pulse for carbon • Furthermore, the decoupler) is on during acquisition, but is off during relaxation and between pulses • Proton nOe is filtered in acquisition & further by processing the early part of the 13C FID • Then, the carbon signals are integrated (b’) (a, a) (c’) (c) (b) (b’)
ECS-7.3 Quantitative 13C NMR (d’) # epoxy groups / sucrose = [(epoxy integrals) / (olefin + epoxy integrals)] x 8 (d) (b’ cis) (b’) trans (b) (c)
200 100 150 100 50 200 150 50 ppm ppm EMS-5.6 Quantitative 13C NMR Methallyl sucroses Epoxy methallyl sucroses
New Chemistry With Cellulose • Cellulose • b-1-4 linked poly(anhydroglucose) with P2 symmetry • 3 OH groups have different reactivities • Not used as an asymmetric starting polymer for chirons • bears protection at the 1,4-ends • What are the rules for asymmetric reactions with cellulose?
Cellulose Epoxides & Addition? “manno” “allo” • Selective synthesis methods? • Where will the nucleophile add? • Effect of the remote hydroxyl group when protected or unprotected?
Complete Characterization of Cellulose Derivatives • Polymers for Advanced Technologies, 1999, 10, 311-320 • J. Poly. Sci.: Part A: Poly. Chem. Ed., 1999, 37, 4019-4032 • J. of Poly. Sci.: Part A: Poly. Chem. Ed., 2000, 38, 1889-1902 • Polymers for Advanced Technologies, 2002, 13, 413-427 • Polymers for Advanced Technologies.2002, 13, 66-79 • ACS Symposium Series 834, NMR Spectroscopy of Polymers in Solution and in the Solid State. American Chemical Society, Washington DC, 2003, 306-323 Work not published
Total Correlation (TOCSY) Spectrum of the Anhydroglucose Portion of Allyl Cellulose
1H-1H COSY Spectrum of of the Allyl Appendages of the Polymer
Heteronuclear Single Quantum Coherence (HSQC) Spectrum of Allyl Cellulose Spectrum shows one-bond correlations
Heteronuclear Multiple Bond Correlation (HMBC) Spectrum of Allyl Cellulose Spectrum connects 1H and 13C nuclei 2 and 3 bonds away
Total Correlation Spectroscopy TOCSY Spectrum of the Olefin Portion of Allyl Cellulose
Heteronuclear Multiple Bond Correlation (HMBC) Spectrum of the Olefin Portion of Allyl Cellulose
Crotyl to Epoxy Crotyl Celluloses Unlike allyl celluloses, epoxidation of crotyl celluloses is controlled: • 11, 33, 66, and 75% epoxidation obtained • Reactivity = 6 > 3 > 2 Crotyl celluloses Epoxy crotyl celluloses
2D-HSQC and Partial Line List (-ppm, CDCl3) 6 6a 2a 3a
2D-HSQC ECC-33% 3c(e) 6c(e) 6b(e) 6a(e)
Complete Chemical Shift Assignments of Crotyl and Epoxy Crotyl Celluloses
Acknowledgements • Funding through USDA ARS • Cooperative Agreement # 58-91H2-0-319 • CRIS # 6435-41000-064-00D • CRIS # 6435-41000-081-00D