The main issue of this manuscript is the exploration of the solubility of methacrylic acid (MA), and the oligomers of poly(ethylene glycol) methyl ether (MPEG), poly(ethylene glycol) methacrylate (PEGMA), and a mixture of MA and PEGMA. These solutions obey to the class of associating aqueous solutions as hydrogen bonding plays an essential role. All solutions are miscible at ambient temperature. Only a small fraction of the order of 10−5 molecules is involved in a process of aggregation forming about 0.4 μm diameter large colloids whose volume fraction enhances above 70 °C. This increase of aggregation is going hand and hand with phase separation of the solution at temperatures at about 70 °C and above. Spinodal and binodal temperatures of the solutions were determined from thermal composition fluctuations following mean field and renormalized 3D-Ising behavior in dependence of the distance from the spinodal phase boundary.
- Associating polymer solution
- Critical behavior of thermal fluctuations
- Lower critical solution behavior