Coaxial electrospinning for the reinforcement of nanofibre mats

Kemp, Renier (2017-03)

Thesis (MSc)--Stellenbosch University, 2017.

Thesis

ENGLISH ABSTRACT: Styrene -N-(N’,N’-dimethyl-3-aminopropyl)maleimide copolymer (SMI-P) was prepared by treating styrene-maleic anhydride copolymer (SMA) with N,N-dimethyl-3-aminopropylamine (DMAPA). The SMI-P copolymer was fully characterized with Fourier Transform Infrared Spectroscopy (FTIR), Differential Scanning Calorimetry (DSC) and Nuclear Magnetic Resonance (NMR) spectroscopy. Thereafter the polymer was co-electrospun with nylon 6 to produce fibres with core-shell morphology. The core-shell morphology was expected to provide a stronger fibre system for application in water filtration. Core-shell fibres of poly(styrene-co-N-(N’,N’-dimethyl-3-aminopropyl) maleimide) (SMI-P) (shell) and nylon 6 (core) were produced through the coaxial electrospinning technique. The fabricated fibres were characterized using Scanning Electron Microscopy (SEM), Scanning Transmission Electron Microscopy (STEM) and Confocal Microscopy (CM) to provide evidence of the core-shell structure formation. Dissolution tests were also carried out in order to provide further certainty that the core-shell morphology was formed. The dip coating technique was evaluated as a second route towards the formation of coaxial fibres. Mechanical tests were performed on both the core-shell fibres and the coated fibres as well as pristine SMI-P fibres to confirm reinforcement of the fibre mats. Antimicrobial tests were performed on the fabricated fibres via two techniques namely the diffusion disc and live/dead fluorescence methods. Both methods were performed on the samples to determine if the SMI-P retained its antimicrobial activity even after fibre reinforcement. The fibres were found to be potent against Staphylococcus aureus, Salmonella typhi, Pseudomonas aeruginosa, Escherichia coli, methicillin-resistant Staphylococcus aureus, and Bacillus subtilis.

AFRIKAANSE OPSOMMING: Stireen-N-(N', N'-dimetiel-3-aminopropiel) maleimiedkopolimeer (SMI-P) is voorberei deur die behandeling van stireen-maleïen anhidriedkopolimeer (SMA) met N,N-dimetiel-3-aminopropielamien (DMAPA). Die SMI-P kopolimeer is ten volle gekaraktiseer met behulp van Fourier-transform infrarooispektroskopie (FTIR), differensiële skandeerkalorimetrie (DSK) en kernmagnetiese resonansie (KMR). Daarna is die polimeer ge-elektrospin met nylon 6 om nanovesels met ’n kern-skilmorfologie te maak. Daar is verwag dat die kern-skilmorfologie n sterker veselstelsel sou voortbring vir die toepassing in waterfiltrasie. Kern-skilvesel van poli(stireen-N-(N',N'-dimetiel-3-aminopropiel) maleimiedkopolimeer (SMI-P) (skil) en nylon 6 (kern) is voorberei met die koaksiale elektrospintegniek. Die vervaardigde vesel is gekarakteriseer met behulp van skandeerelektronmikroskopie (SEM), skanderingstransmissie elektronmikroskopie (STEM) en konfokale mikroskopie (KM) om bewys te lewer van die kern-skil struktuurvorming . Ontbindingstoetse is ook gedoen om verder te bewys dat die kern-skilmorfologie bereik is. Die dompellaagtegniek is geëvalueer as 'n tweede roete vir die vorming van koaksiale nanovesels. Meganiese toetse is uitgevoer op die kern-skilvesel en die bedekte vesel, asook ongerepte SMI-P vesel om die versterking van die veselmatte te bevestig. Antimikrobiese toetse is uitgevoer op die voorbereide nanovesels deur twee tegnieke, naamlik die sone inhibisie en lewende/dooie fluoressensie metodes, te gebruik. Beide metodes is uitgevoer op die monsters om te bepaal of die SMI-P sy antimikrobiese aktiwiteit na veselversterking behou. . Daar is bevind dat die vesels aktief is teen Staphylococcus aureus, Salmonella typhi, Pseudomonas aeruginosa, Escherichia coli, metisillienweerstandige Staphylococcus aureus, asook Bacillus subtilis.

Please refer to this item in SUNScholar by using the following persistent URL: http://hdl.handle.net/10019.1/101240
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