Thesis (MSc)--Stellenbosch University, 2000. / ENGLISH ABSTRACT: Various companies produce waxes, which are used extensively in various applications, either as
produced or as chemically or physically modified value-added products. They are used in the
traditional candle industry and applications including hot melt adhesives, inks, plastics, polishes
and emulsions for rust prevention or fruit coating. Insight into the properties of these waxes is
required to assist the applications chemist in understanding the role of the wax component in a
specific formulation.
Analytical techniques such as differential scanning calorimetry (DSC), thermogravimetry (TG),
rheometry, gel permeation chromatography (GPC), high temperature gas chromatography
(HTGC) and infra-red spectroscopy (IR) were used to characterise Fischer Tropsch, polyethylene,
natural and petroleum waxes. Property profiles were formulated by integrating the results from
the various techniques. The results of traditional wax analyses (e.g. congealing point, melting
point, penetration, density and viscosity) were also correlated to relevant analytical results
obtained from the instrumental techniques. Structure-property relationships have been proposed. / AFRIKAANSE OPSOMMING: Verskeie maatskappye vervaardig wasse, wat in menige toepassings gebruik word - of direk, of
as chemies- of fisies- veranderde produkte van hoër waarde. Benewens die tradisionele
kersbedryf, word die wasse in toepassings soos warmsmeltkleefmiddels, ink, plastiek,
roeswerende- en vrugtebedekkings- emulsies en politoere gebruik. Wetenskaplikes betrokke by
die formuleering van wasse vir verskillende toepassings sal baat vind by beter inligting van
waseienskappe en die rol van waskomponente in formulasies.
Tegnieke, bv. differensialeskandeerkalorimetrie (DSC), termogravimetrie (TG), reologie,
gelpermeasiechromotografie (GPC), hoëtemperatuurgaschromatografie (HTGC) en infrarooispektroskopie
(IR), is gebruik om Fischer Tropsch-, polietileen-, petroleum- en natuurlike wasse
te karakteriseer. Profiele van waseienskappe is geformuleer deur die integrasie van die
data verkry van die verskillende analitiese tegnieke. Die resultate van tradisionële wasanalises
(bv. stolpunt, smeltpunt, penetrasie, digtheid, viskositieit en olie-inhoud) word ook in verband
gebring met die resultate van die instrumentele analises. Verbande tussen struktuur en
waseienskappe word ook voorgestel.
| Identifer | oai:union.ndltd.org:netd.ac.za/oai:union.ndltd.org:sun/oai:scholar.sun.ac.za:10019.1/52055 |
| Date | 12 1900 |
| Creators | Webber, Glenda Vanessa |
| 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 | English |
| Type | Thesis |
| Format | 116 p. : ill. |
| Rights | Stellenbosch University |
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