Atom transfer radical polymerisation of unusual monomers

Staisch, Ingrid (2003-12)

Thesis (MSc)--Stellenbosch University, 2003.

Thesis

ENGLISH ABSTRACT: Controlled free radical polymerisation techniques offer several practical and theoretical advantages compared to many other polymerisation techniques. Living polymerisation techniques such as anionic polymerisations require the total exclusion of impurities such as oxygen and moisture. Controlled free radical polymerisations, however, do not require such stringent methods of practice. This is very advantageous for industrial purposes. Atom Transfer Radical Polymerisation (ATRP) is a form of a controlled/living free radical polymerisation technique by which one is able to synthesize controlled architectural structures and predetermine the molecular weights of macromolecules. The monomers that were investigated for this research project include methyl methacrylate (MMA), 4-vinylpyridine (4VP) and lauryl methacrylate (LMA). The latter two monomers (4VP and LMA) are not commonly used in ATRP-mediated reactions. The synthesis of block copolymers ofMMA and LMA were attempted. The homopolymerisation of 4VP did not give the control expected when polymerising by means of ATRP. This prompted an investigation into possible side reactions that could take place with 4VP in this specific ATRP system. This included possible quatemization of 4VP with the alkyl halide initiator species.

AFRIKAANSE OPSOMMING: Beheerde vrye-radikaalpolimerisasietegnieke bied verskeie praktiese en teoretiese voordele bo verskeie ander vrye-radikaalpolimerisasietegnieke. Lewende polimerisasietegnieke soos anioniese polimerisasie, vereis die totale uitsluiting van onsuiwerhede soos suurstof en water. Beheerde vrye-radikaalpolimerisasies vereis egter nie sulke streng reaksiekondisies nie. Hierdie is baie voordelig vir industriële doeleindes. Atoomoordragradikaalpolimerisasie (ATRP) is 'n tipe beheerde/lewende vryeradikaalpolimerisasietegniek wat dit moontlik maak om die samestelling en struktuur van makromolekules asook die molekulêre massa presies te beheer. In hierdie studie is die monomere metielmetakrilaat (MMA), 4-vinielpiridien (4VP) en laurielmetakrilaat (LMA) bestudeer. Laasgenoemde twee monomere (4VP en LMA) word beskou as ongewone monomere om in ATRP-sisteme te gebruik. Daar is gepoog om blok kopolimere van MMA en LMA te sintetiseer. Die homopolimerisasie van 4VP het minder beheer gelewer as wat by beheerde vrye-radikaal sisteme soos hierdie verwag word. Na aanleiding van hierdie resultate is 'n ondersoek geloods om die moontlike newereaksies van 4VP in hierdie spesifieke ATRP-sisteem te ondersoek. Daar is gepoog om te bewys dat die alkielchloriedinisieerder verdwyn deur kwatemisasie met 4VP.

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