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dc.contributor.authorSaunders, Charles Williamen
dc.date.accessioned2014-03-14T21:16:47Zen
dc.date.available2014-03-14T21:16:47Zen
dc.date.issued1990en
dc.identifier.otheretd-07282008-135448en
dc.identifier.urihttp://hdl.handle.net/10919/38966en
dc.description.abstractThe object of this research was the development of on-line methods for the determination of the degree of substitution of cellulose esters. The focus of the effort was on the application of a Fourier transform infrared spectrometer (FT-IR) as an in-line detector for quantitative gel permeation chromatography (GPC). GPC/FT-IR has been used in the analysis of polymeric materials in the past, but not for quantifying the substituent content of cellulosics. This work has identified the infrared asymmetric nitrate absorptions of cellulose nitrates observed in THF and acetonitrile solutions. Independent absorptions for the primary nitrate at C₆ and secondary nitrate at C₃ were observed at 1651 cm⁻¹ and 1639 cm⁻¹ respectively. In addition, a third absorption at 1667 cm⁻¹ was observed to be dependent upon the degree of nitration of the cellulose nitrate. This absorption was found to be due to steric hindrance between secondary nitrate groups on the C₂ and C₃ sites. The infrared absorptions of cellulose acetate butyrates in THF, acetonitrile, and methylene chloride were also characterized. Separate absorptions for the acetyl and butyryl C-O-C asymmetric stretch were observed at 1235 cm⁻¹ and 1176 cm⁻¹ respectively. In acetonitrile and methylene chloride the carbonyl asymmetric stretching mode frequency observed at ≈1753 cm⁻¹ was found to be dependent upon the extent of acetyl substitution. This work developed a method for the quantitative determination of the degree of nitration of cellulose nitrates as a function of the polymer molecular weight using the asymmetric nitrate stretch. Methods for the determination of the acetyl and butyryl substitution of cellulose acetate butyrates were developed as well. Examples of each method applied to real world samples were carried out.en
dc.format.extentxiv, 216 leavesen
dc.format.mediumBTDen
dc.format.mimetypeapplication/pdfen
dc.language.isoenen
dc.publisherVirginia Techen
dc.relation.isformatofOCLC# 22215219en
dc.relation.haspartLD5655.V856_1990.S286.pdfen
dc.rightsIn Copyrighten
dc.rights.urihttp://rightsstatements.org/vocab/InC/1.0/en
dc.subject.lccLD5655.V856 1990.S286en
dc.subject.lcshCellulose -- Spectra -- Researchen
dc.titleCharacterization of cellulose esters via GPC/FT-IRen
dc.typeDissertationen
dc.contributor.departmentChemistryen
dc.description.degreePh. D.en
thesis.degree.namePh. D.en
thesis.degree.leveldoctoralen
thesis.degree.grantorVirginia Polytechnic Institute and State Universityen
thesis.degree.disciplineChemistryen
dc.type.dcmitypeTexten
dc.identifier.sourceurlhttp://scholar.lib.vt.edu/theses/available/etd-07282008-135448/en
dc.date.sdate2008-07-28en
dc.date.rdate2008-07-28en
dc.date.adate2008-07-28en


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