Benign Metal Photoactive Initiators for Biopolymer Production

: (Alternative Format Thesis)

Abstract

The current use and production of plastic poses a major threat to the world. The non-degradable nature of commodity plastics renders them unsustainable for future use, however the benefits they provide to society cannot be underestimated. The only solution to this exceptionally difficult and extensive challenge is to ramp-up research efforts which offer more sustainable solutions, whilst retaining or bettering the advantageous characteristics of these materials. The overarching aims of this PhD are to provide innovative solutions to this challenge through the careful design and synthesis of catalysts which can produce degradable materials. Biodegradable polyesters such as polylactic acid (PLA), polycaprolactone (PCL) and δ-valerolactone (VL) boast many of the characteristics required to replace plastics derived from finite supplies of crude oil.

Switchable ring-opening polymerisation (ROP) techniques provide many benefits including the ability to carefully control the reaction using an external trigger. This often allows greater control over the reaction rate and morphology of the final material, depending on when the external trigger is applied. Switchable ROP also alleviates the need for hazardous chemicals as the reaction can be controlled using stimuli such as light and heat, which produce far fewer hazardous by-products. Although this is a relatively new area of research, the literature suggests that this area of polymer chemistry could become increasingly prevalent due to the benefits outlined above. The desire to synthesise polymers with more exotic and novel architectures also requires polymer chemists to come up with innovative ways to achieve this.

Incorporating stimuli-responsive units into a catalyst can allow catalysts to be transformed into more powerful entities. This technique also allows a single catalyst to behave in multiple ways by switching between two or more distinct states. This is particularly important in the formation of copolymers where the activity of a catalyst towards different monomers can be altered by switching between the forms at various points in the reaction. Despite the plethora of benefits offered by these types of catalysts, organometallic light switchable.

Date of Award	29 Mar 2023
Original language	English
Awarding Institution	University of Bath
Supervisor	Matthew Jones (Supervisor) & Antoine Buchard (Supervisor)