The surface tension, or surface free energy, y, of glass is an important parameter for understanding, interpreting and predicting surface and interface phenomena such as wetting and adhesion when glass is associated to other materials like metals, ceramics other glasses and polymers. The series of mineral glasses considered in this study belong to a new family of durable phosphate glasses having a glass transition temperature between 275 and 375 deg C. These glasses are used in the manufacture of Cortem glass/polymer blends. At the compouding and processing temperture of blends, they have a high viscosity which does not permit the simple measurement of surface tension with classical tensiometric techniques. Therefore, a drop shape method which allows easy measurements at high temperature and viscosity has been developed.
