Interfacial Interactions in Polyaniline Containing Hybrids

This thesis is concerned with the interfacial interactions of the components in polyaniline (PANI) containing hybrids. It has focused on the interaction of two groups of substrates with PANI: inorganic fillers and biopolymers. The first group includes model substrates, such as silica and alumina, and also zeolites and clays, where the silanol groups on their surfaces were considered as the target for modification. Stable interaction of PANI with an inorganic substrate was developed via a new facile one-pot and one-step silylation method with an aniline functionalised coupling agent, namely 3- phenylaminopropyltrimethoxysilane (PAPTMOS). The products of silylation were applied to prepare the PANI containing hybrids which were mostly electrically conductive due to the emeraldine salt form of PANI doped with methanesulfonic acid (MSA) being present. The evidence of the formation of the hybrid material and the nature of interactions between the individual components of the hybrid materials were revealed by different characterisation methods, such as FTIR, XPS, Solid state NMR, Elemental analysis (EA), Electrical conductivity measurements, and SEM. The second group of substrates were biopolymers. Zein (corn protein) has been shown to interact with PANI in both heterogeneous (suspension) and homogeneous (solution) conditions. Strong interactions, mostly by means of nitrogen containing and carbonyl groups, were detected in FTIR studies. Zein-PANI(MSA) composites were studied in the forms of powders and films. They were electrically conductive. The powders showed a good free electron scavenging capacity in the DPPH test. A plasticisation effect of PANI on zein matrix was found in films. FTIR spectroscopic studies of the modified zein with the lateral amide groups of Glutamine and Asparagine changing to ester groups confirmed their involvement in the interactions with PANI. Another important biopolymer, cellulose, was attempted in the silylation process with PAPTMOS followed by binding of PANI(MSA). The electrically conductive products in the case of cellulose fibres and cellulose powder were obtained. In comparison with untreated celluloses, PANI was strongly connected to the silylated cellulose surface and could not be removed with common solvents. Thus the current research promises a novel and facile pathway to create stable PANI containing hybrid materials based on commercially available inorganic and organic substrates.

Name thesis:degree_name

PhD

Level thesis:degree_level

Doctoral

Grantor dc:publisher

ResearchSpace@Auckland

Year dc:date.issued

2013

Author dc:creator

• Wheelwright, Walt

Advisors dc:contributor.advisor

• Cooney, R
• Ray, S
• Easteal, A

Statement dc:rights

• Items in ResearchSpace are protected by copyright, with all rights reserved, unless otherwise indicated. Previously published items are made available in accordance with the copyright policy of the publisher.

Licence dc:rights.uri

• https://researchspace.auckland.ac.nz/docs/uoa-docs/rights.htm

Handle dc:identifier.uri

https://hdl.handle.net/2292/20512

OAI identifier oai:identifier

oai:researchspace.auckland.ac.nz:2292/20512