E-Thesis 346 views 416 downloads
Novel Porous Polymers as Flame Retardant and Gas Separation Materials / YUE WU
Swansea University Author: YUE WU
DOI (Published version): 10.23889/SUthesis.68363
Abstract
Nowadays, polymer materials have permeated every aspect of our daily life, bringing not only convenience but also fire hazards. The limiting oxygen index of most polymer materials is lower than 21, that means they are flammable or combustible in air. A large amount of toxic and corrosive smoke and g...
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Swansea University, Wales, UK
2024
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| Institution: | Swansea University |
| Degree level: | Doctoral |
| Degree name: | Ph.D |
| Supervisor: | Carta, M. |
| URI: | https://cronfa.swan.ac.uk/Record/cronfa68363 |
| Abstract: |
Nowadays, polymer materials have permeated every aspect of our daily life, bringing not only convenience but also fire hazards. The limiting oxygen index of most polymer materials is lower than 21, that means they are flammable or combustible in air. A large amount of toxic and corrosive smoke and gas are released during combustion, that pose a big threat to people's safety and cause environmental pollution. Therefore, the development of flame retardant materials has attracted the attention of researchers around the world.This project aims to develop novel PIM-based flame retardant additives. Specifically, we designed three series of PIM materials. The first discussion chapter includes the preparation of boroxine and boronic ester-based PIMs. We verified the feasibility of boroxine network polymerisation and its satisfactory thermal decomposition behaviour.Boronic ester-PIMs containing different contorted units were synthesized using two different heating devices and compared in terms of purity, thermal stability and porosity, especially to understand if porosity influences the flame retardation capability. It was shown that their thermal properties meet the requirements of standard flame retardant additives. The second series shows PIMs composed of hexaphenylbenzene core units and Tröger’s Base linkages with different C/N ratios and porosities, as it is known that increasing the amount of N per repeat unit improves the thermal stability. It was confirmed that these polymers have excellent thermal properties, which can be enhanced by increasing their functionality, i.e., improving their content of nitrogen and porosity. In the third series, cyclophosphazene was polymerised respectively with catechols and amines using two heating methods. This is a very challenging and new method to make phosphorous-containing PIMs. Two catechol-based polymers were successfully obtained and exhibited desirable thermal decomposition behaviours. The preparation of the amine-based polymer was preliminarily explored as well.Furthermore, the performance of the novel PIMs from series 1 and 2 in gas separation was also investigated. (Polymers from series 3 were excluded due to their low specific surface areas.) The results also indicated that the high heteroatom content, specific surface area and narrow microporosity helped to improve both the CO2 uptake and CO2/N2 selectivity of the materials. |
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| Item Description: |
A selection of content is redacted or is partially redacted from this thesis to protect sensitive and personal information. |
| Keywords: |
PIMs, Boroxine, Boronic ester, Hexaphenylbenzene, Tröger’s base, Cyclophosphazene, Flame retardant, Gas separation |
| College: |
Faculty of Science and Engineering |
| Funders: |
EPSRC |