Phase and aggregational studies of some inversely soluble aqueous formulations

The effect of component molecular structure, pH, temperature and concentration on phase and aggregational behaviour of aqueous formulations containing more than one polydisperse polyglycol ether based compound was studied. The effect of adding various inversely soluble polymer compounds to base formulations on surface tension, turbidity, conductivity and pH over a wide range of temperatures and concentrations in water was investigated. A new instrument, enabling automatic temperature and concentration scans, was used for the generation of pH, turbidity and conductivity data. It was observed that phase behaviour of polyalkylene glycol ethers is dramatically changed by the presence of surface active components. Results also show that the amount and type of polymer has a small effect on the critical micelle concentration (CMC) but is critical for the phase behaviour of the investigated formulations. Molecular weight, hydrophile–lipophile balance (HLB) as well as cloud point values are important parameters which may be varied widely and a proper choice of polyalkylene glycol can be used to affect phase separation behaviour with respect to desired performance in industrial applications, e.g. as lubricants in metal working fluids.