Date of Award

Spring 2012

Degree Type


Degree Name

Master of Applied Science (MASc)


Chemical Engineering


Shiping Zhu




In this thesis work, two new CO2-responsive monomers have been synthesized. These amidine-containing monomers were prepared in a simple and effective one-step reaction, giving a very high yield (98.5 %) of product. Furthermore, there was no complicated further purification required to obtain the highly pure product. The CO2 switchability, conductivity and partitioning of the monomers were measured. It was confirmed that the monomers could be protonated CO2 in the present of trace amount of water and reversibly switched back and forth to their natural forms by N2 at room temperature.

The polymers having different molecular weights were prepared from one monomer via conventional free radical polymerization method. The polymers also showed the reversible switchability property with CO2 and N2 stimuli. This was confirmed by the results of conductivity and partitioning tests. Temperature showed a major influence on the conductivity of the monomer and polymers. The effect of molecular weight on the polymer switchability of was further investigated through conductivity tests and potentiometric titration. The conductivity decreased with the increased molecular weight. The apparent equilibrium constant (pKa) decreased with the degree of protonation (δ) suggesting that the basicity of the polymers is strongly depended on the value of δ.

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