A series of amphiphilic thermoresponsive ABC triblock copolymers was synthesised by Group Transfer Polymerisation (GTP). In total nine polymers were prepared based on the non-ionic hydrophobic n-butyl methacrylate (BuMA), the ionisable hydrophilic and thermoresponsive 2-(dimethylamino)ethyl methacrylate (DMAEMA) and the non-ionic hydrophilic methoxy poly(ethylene glycol) methacrylate (PEGMA). The architecture of the copolymers was kept constant with the hydrophobic block in the middle and the two hydrophilic blocks at the two ends, while the composition and the molecular weight of the polymers were varied. Specifically the molecular weight of the polymers was varied while the composition and the architecture were kept constant. The precursors to the polymers and the polymers were characterised in terms of their molecular weight and composition using gel permeation chromatography and proton nuclear magnetic resonance spectroscopy, respectively. Aqueous solutions of the polymers were studied by turbidimetry, hydrogen ion titration and light scattering to determine their cloud points, pKas, and hydrodynamic diameters and investigate the effect of the composition and the molecular weight of the copolymers. Finally, the thermoresponsive behaviour of the copolymers was also studied and it was found that the cloud point and gel point of the polymers were strongly affected by both the composition and molecular weight of the triblock copolymers.
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