Thesis (MSc)--Stellenbosch University, 2015. / ENGLISH ABSTRACT: Impact polypropylene copolymers (IPC) are commercially used in a variety of applications. They
are very complex materials and extensive studies have been conducted to understand the
relationship between their chemical structure, morphology and impact properties. The distribution
of ethylene propylene rubber (EPR) within IPC has drawn much attention but visualization of the
morphology is difficult. In this study a fluorescent marker was used to probe the distribution of
EPR within the crystalline and semi-crystalline fraction.
The EPR was removed from a commercial IPC and labelled with a fluorescent marker. In this
study a method utilizing the hydrophilic nature of cellulose nanowhiskers (CNW) was developed to
label the EPR. CNW were labelled with fluorescein-5’-isothiocyanate (FITC) and rhodamine B
(RhB) using a one-step procedure. The labelled CNW were incorporated into the EPR by means
of sonication. The mobility of the labelled CNW within the EPR film was investigated by confocal
fluorescence microscopy (CFM), and showed that the labelled whiskers did not move within the
EPR, thus substantiating the validity of this approach. The labelled EPR was recombined with the
crystalline fraction by means of injection moulding and was analysed by CFM, and the distribution
of the labelled EPR was evaluated. Confocal fluorescence microscopy showed an even distribution
of the labelled rubber throughout the injection moulded sample.
The miscibility of two EPRs within the IPC matrix in the melt was also investigated using this
technique. CFM showed that the technique has promise to prove miscibility or the lack thereof
when chemically similar materials are combined in the presence of morphologically different matrix
materials. / AFRIKAANSE OPSOMMING: Impak polipropileen kopolimere (IPK) word kommersieel gebruik in ‘n wye reeks produkte. Die
samestelling van hierdie kopolimere is baie ingewikkeld en uitgebreide studies is al gedoen om hul
chemiese samestelling op molekulêre vlak te verstaan. Baie studies met betrekking tot die
verspreiding van die etileen-propileen rubber (EPR) binne in hierdie impak polipropileen
kopolimere is al gedoen, maar visualisering van die morfologie is moeilik en beperk. Hierdie kennis
kan bydra tot die verbetering van hul chemiese eienskappe en toepassings. In hierdie studie word
ʼn fluorosserende merker gebruik om die verspreiding van die EPR binne die kristallyne en semikristallyne
fraksie te ondersoek.
Die EPR is verwyder vanuit 'n kommersiële IPK en is gemerk met 'n fluoresserende merker. In
hierdie studie is 'n metode ontwikkel om die EPR te merk deur gebruik te maak van die hidrofiliese
eienskap van sellulose nanovesels (SNV). Die SNV is gemerk met fluoressien-5'-isotiosianaat
(FITC) en rhodamien B (RhB) met behulp van 'n eenstap proses. Die gemerkte SNV is deur middel
van sonikasie in die EPR versprei. Die mobiliteit van die gemerkte SNV binne-in die EPR film is
ondersoek deur gefokusde fluoressensie mikroskopie (GFM) en het getoon dat die gemerkte
vesels nie binne die EPR beweeg nie. Dit bevestig dus die geldigheid van hierdie benadering. Die
gemerkte EPR is herkombineer met die kristallyne fraksie deur middel van spuitgiet en is
geanaliseer deur GFM en die verspreiding van die gemerkte EPR is geëvalueer. GFM het 'n
eweredige verspreiding van die gemerkte rubber regdeur die moster wat gespuitgiet is getoon.
Die mengbaarheid van twee EPRs binne-in die IPK matriks is ook ondersoek deur gebruik te maak
van hierdie tegniek. GFM het getoon dat hierdie tegniek waarde inhou om te bewys dat twee
produkte mengbaar is of nie, al word hulle geherkombineer word met ‘n matriks wat morfologiese
van hul verskil.
| Identifer | oai:union.ndltd.org:netd.ac.za/oai:union.ndltd.org:sun/oai:scholar.sun.ac.za:10019.1/96820 |
| Date | 04 1900 |
| Creators | Le Grange, Marehette Suzanne |
| Contributors | van Reenen, Albert, Lutz, Marietjie, Stellenbosch University. Faculty of Science. Dept. of Chemistry and Polymer Science |
| Publisher | Stellenbosch : Stellenbosch University |
| Source Sets | South African National ETD Portal |
| Language | en_ZA |
| Detected Language | English |
| Type | Thesis |
| Format | xvi, 94 pages : colour illustrations |
| Rights | Stellenbosch University |
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