Thesis (MSc)--Stellenbosch University, 2004. / ENGLISH ABSTRACT: In the ongomg search for better and faster ways to characterize complex polymer
systems, it is often necessary to couple different analytical techniques in order to obtain
information on more than one distributed property. In this study, the coupling of
chromatography and spectroscopy to atomic force microscopy (AFM) was attempted for
the first time, and thus the term "LC-FTIR-AFM" was coined. This new hyphenated
technique combines the separation power of liquid chromatography (LC) and the ability
of infrared spectroscopy (IR) to identify almost any organic compound, with the AFM's
ability to be used for thermal analysis of individual phases in polymer mixtures.
The first two steps of this new technique comprise (i) the separation of compounds in a
mixture via gradient polymer elution chromatography (GPEC) and (ii) the identification
of each compound by means of LC-FTIR analysis. In the final step, LC-FTIR analysis is
coupled to AFM through the use of the LC-FTIR interface.
A number of polymer mixtures were analysed by means of the novel technique that was
developed, in order to establish its validity and value as a characterization technique of
the future. The influence of fllm thickness and molar mass on the thermal parameters of
individual components in mixtures, measured by this technique, were also investigated.
This technique adds a new dimension to conventional thermal analysis methods, since it
allows the thermal transitions of individual polymer phases in multiphase polymers to be
resolved directly after separation and identification. / AFRIKAANSE OPSOMMING: In die voortdurende soektog na beter en vinniger maniere om komplekse polimeersisteme
te karakteriseer, is dit soms nodig om verskillende analitiese tegnieke met mekaar te
koppel ten einde inligting aangaande twee of meer verspreide eienskappe te bekom.
Gedurende hierdie studie is daar gepoog om chromatografie en spektroskopie met
atoominteraksie-mikroskopie (atomic force microscopy, AFM) te koppel. Gevolglik het
die term "LC-FTIR-AFM" ontstaan. Hierdie nuwe koppelingstegniek kombineer die
kragtige skeidingspotensiaal van vloeistofchromatografie en die vermoë van
infrarooispektroskopie om byna enige organiese verbinding positief te identifiseer, met
die atoominteraksie-mikroskoop se potensiaal om as 'n termiese analise metode vir
individuele fases in polimeermengsels te dien.
Die eerste twee stappe van die tegniek behels (i) die skeiding van verbindings in 'n
mengsel deur middel van gradient-hoë-druk-vloeistofchromatografie en (ii) die
identifisering van afsonderlike verbindings deur vloeistofchromatografie gekoppel aan
infrarooispektroskopie. Gedurende die finale stap word vloeistofchromatografie en
infrarooispektroskopie aan die atoominteraksie-mikroskoop gekoppel deur gebruik te
maak van die LC-FTIR koppelingsapparaat.
'n Aantal polimeermengsels is geanaliseer deur die nuwe tegniek hierbo beskryf, ten
einde die geldigheid en waarde daarvan as 'n analitiese metode vir die toekoms vas te
stel. Die invloed van film diktes en molekulêre massa op die termiese oorgange van
individuele komponente in mengsels, soos gemeet deur hierdie metode, is ook ondersoek.
Hierdie tegniek voeg 'n nuwe dimensie tot konvensionele termiese analise metodes
deurdat dit die bepaling van termiese oorgange van individuele polimeerfases III
multifase polimere, direk na afloop van skeiding en identifikasie moontlik maak.
| Identifer | oai:union.ndltd.org:netd.ac.za/oai:union.ndltd.org:sun/oai:scholar.sun.ac.za:10019.1/53766 |
| Date | 03 1900 |
| Creators | De Goede, E. (Elana) |
| Contributors | Sanderson, R. D., Stellenbosch University. Faculty of Science. Dept. of Chemistry & Polymer Science. |
| Publisher | Stellenbosch : Stellenbosch University |
| Source Sets | South African National ETD Portal |
| Language | en_ZA |
| Detected Language | Unknown |
| Type | Thesis |
| Format | 117 p. : ill. |
| Rights | Stellenbosch University |
Page generated in 0.0091 seconds