Bottlebrush block copolymers for photonic materials

Block copolymer self-assembly has proven to be an effective route for the fabrication of photonic films and, more recently, photonic pigments. However, despite extensive research on this topic over the past two decades, the palette of monomers and polymers employed to produce such structurally coloured materials has remained surprisingly limited. In this dissertation, a series of biocompatible bottlebrush block copolymers (BBCPs) have been synthesised based upon polyester or polyether macromonomers, including: polylactide, polycaprolactone, or polyethylene glycol. These BBCPs are self-assembled within emulsified droplets into microparticles with a photonic glass architecture that reflects vibrant structural colour. Importantly, a full-colour palette of such ‘photonic pigments’ can be achieved by changing either the BBCP properties (e.g., composition, molecular weight) or the microparticle fabrication conditions (e.g., temperature, time). The relationship between the morphology of the BBCP microparticles and their optical response was ascertained, which allowed for a strategy to enhance the colour purity to be developed. Finally, by investigating BBCPs with similar composition, but different thermal behaviours, it allowed for the mechanism underlying the formation of the internal nanoarchitecture to be understood. Beyond improving the biocompatibility of the BBCPs used for photonics, their end-of-life pathway was also considered. Through the insertion of a degradable linkage into the BBCP backbone, they could be broken down into low molecular weight oligomers under mild conditions. This was demonstrated by incorporating a silyl ether into a polyester-based BBCP, which was exploited in the development of degradable photonic materials based upon lamellar architectures. Overall, the biocompatible and degradable BBCPs developed over the course of these studies will provide the photonics community with a new direction to explore when seeking to resolve the outstanding issue regarding the sustainability of artificial colourants.

Name dc:type.qualificationname

Doctor of Philosophy (PhD)

Level dc:type.qualificationlevel

Doctoral

Grantor dc:publisher.institution

University of Cambridge

Year dc:date.issued

2023

Author dc:creator

• Wang, Zhen

Advisor dc:contributor.advisor

• Vignolini, Silvia

• biocompatibility
• block copolymer
• degradability
• photonic glass
• photonic material
• photonic multilayer
• self-assembly
• structural colour
• sustainability

Licence

• https://apollo8-f-pro.lib.cam.ac.uk/bitstreams/de28686c-c36e-4a6f-b917-9a8181a22d5b/download
• http://purl.org/NET/rdflicense/allrightsreserved

Language dc:language

eng

Author Identifier

0000-0002-0331-8271

OAI identifier oai:identifier

oai:www.repository.cam.ac.uk:1810/362296