Thermoresponsive Gels: How do the structural parameters affect the gelation properties?
File(s)
Author(s)
Constantinou, Anna
Type
Thesis
Abstract
Thermoresponsive polymers are promising biomaterials in Tissue Engineering and in 3D
printing. Therefore, this PhD thesis aims to synthesise polymers that form physical gels at body
temperature (b.t.). Four different families of thermoresponsive polymers have been
successfully synthesised via Group Transfer Polymerisation, and their properties have been
investigated, with emphasis on their thermogelling behaviour.
i) In the first study, the ionic, pH- and thermoresponsive 2-(dimethylamino) ethyl
methacrylate (DMAEMA) has been combined with the hydrophilic tri(ethylene glycol) methyl
ether methacrylate (TEGMA), and the hydrophobic n-butyl methacrylate (BuMA). The
architecture of diblock terpolymers has been systematically varied for the first time, while
statistical and triblock terpolymers have been investigated for comparison.
ii) In the second study, penta(ethylene glycol) methyl ether methacrylate (PEGMA) has been
used as the hydrophilic unit, whereas BuMA and DMAEMA have been kept the same as in the
first study. Thermoresponsive tetrablock terpolymers of varying architectures and
compositions have been systematically investigated for the first time.
iii) The third study is focused on investigating polymers containing a non-ionic
thermoresponsive unit, namely di(ethylene glycol) methyl ether methacrylate (DEGMA, C
unit). ABC triblock terpolymers of various compositions have been synthesised, with A and B
blocks being based on PEGMA and BuMA, respectively.
iv) The fourth study focuses on mimicking Pluronic® F127, which is the commercially-available
thermoresponsive polymer. ABA triblock bipolymers with different molar mass
(MM) and composition have been produced (A is PEGMA, an B is the in-house synthesised
hydrophobic monomer di(propylene glycol) methyl ether methacrylate (diPGMA).
In conclusion, the following structural parameters have been identified as crucial for the
thermogelling properties: i) architecture, ii) composition, iii) MM and iv) as expected, the
chemistry. The best architecture is the ABC triblock architecture with the hydrophobic
monomer as the B block, while the most promising chemistry seems to be the PEGMA-BuMA-DEGMA
series.
printing. Therefore, this PhD thesis aims to synthesise polymers that form physical gels at body
temperature (b.t.). Four different families of thermoresponsive polymers have been
successfully synthesised via Group Transfer Polymerisation, and their properties have been
investigated, with emphasis on their thermogelling behaviour.
i) In the first study, the ionic, pH- and thermoresponsive 2-(dimethylamino) ethyl
methacrylate (DMAEMA) has been combined with the hydrophilic tri(ethylene glycol) methyl
ether methacrylate (TEGMA), and the hydrophobic n-butyl methacrylate (BuMA). The
architecture of diblock terpolymers has been systematically varied for the first time, while
statistical and triblock terpolymers have been investigated for comparison.
ii) In the second study, penta(ethylene glycol) methyl ether methacrylate (PEGMA) has been
used as the hydrophilic unit, whereas BuMA and DMAEMA have been kept the same as in the
first study. Thermoresponsive tetrablock terpolymers of varying architectures and
compositions have been systematically investigated for the first time.
iii) The third study is focused on investigating polymers containing a non-ionic
thermoresponsive unit, namely di(ethylene glycol) methyl ether methacrylate (DEGMA, C
unit). ABC triblock terpolymers of various compositions have been synthesised, with A and B
blocks being based on PEGMA and BuMA, respectively.
iv) The fourth study focuses on mimicking Pluronic® F127, which is the commercially-available
thermoresponsive polymer. ABA triblock bipolymers with different molar mass
(MM) and composition have been produced (A is PEGMA, an B is the in-house synthesised
hydrophobic monomer di(propylene glycol) methyl ether methacrylate (diPGMA).
In conclusion, the following structural parameters have been identified as crucial for the
thermogelling properties: i) architecture, ii) composition, iii) MM and iv) as expected, the
chemistry. The best architecture is the ABC triblock architecture with the hydrophobic
monomer as the B block, while the most promising chemistry seems to be the PEGMA-BuMA-DEGMA
series.
Version
Open Access
Date Issued
2018-09
Date Awarded
2019-03
Copyright Statement
Creative Commons Attribution NonCommercial Licence
License URL
Advisor
Georgiou, Theoni
Jones, Julian
Stingelin, Natalie
Sponsor
Imperial College London
Publisher Department
Materials
Publisher Institution
Imperial College London
Qualification Level
Doctoral
Qualification Name
Doctor of Philosophy (PhD)