Quantum chemical calculations of surfactant having suppression effect on water trees

Polyethylene (PE) is a hydrophobic polymeric insulating material. It has been found that adding hydrophilic additives can enhance the water tree resistance of PE. On the other hand, a surfactant contains both hydrophobic and hydrophilic groups in its molecular structure. It is considered that a surfactant added to PE surrounds water molecules and stabilizes them. Hence, it is highly plausible that the solubilization of moisture in a supersaturated state leads to the suppression of water tree initiation in PE. In this study, we perform quantum chemical calculations of a surfactant using Gaussian 09 to reveal the mechanism of such a suppression effect on water tree initiation. A comparison of the computational results with the results of experiments suggests that the addition of surfactant is extremely effective in suppressing bow-tie water trees.