Silicate Esters and Related Compounds

Temperature dependence of surface layering in a dielectric liquid

“…The molecule has a diameter of about 10 Å. Its freezing temperature and its critical temperature have not been precisely determined, but viscosity measurements 24 indicate that it is a fluid down to at least 219 K. As previously reported, 12 we saw no evidence of a bulk phase transition down to 190 K in either transmission x-ray data or differential scanning calorimetry data. The critical point T c is estimated to be ϳ950 K. 12,25 In order to do this experiment in a closed-cycle refrigerator, we prepared ϳ5000 Å films of TEHOS supported on silicon substrates.…”

Observation of Molecular Layering in Thin Liquid Films Using X-Ray Reflectivity

“…These molecules are approximately spherical, nonreactive under the conditions of this experiment, and nonpolar; also, the vapor pressure is low enough that films will maintain a constant thickness for several hours [12]. The shear flow of bulk TEHOS is Newtonian; its viscosity has been measured down to 240 ± C [17]. Our studies were performed at ϳ20 ± C. The substrates, silicon (111) (Semiconductor Processing Company) with native oxide, were cleaned in strong oxidizer [18].…”

Observation of Surface Layering in a Nonmetallic Liquid

“…It is used in outdoor devices such as transformers and solar cells because it does not freeze in winter and has very low evaporation loss. Neither the freezing point nor the critical point has been precisely determined, but viscosity measurements 20 have shown that it is a fluid down to at least 219K. Using X-ray scattering in transmission, and differential scanning calorimetry, we have found no evidence of a bulk phase transition down to 190K.…”