Properties and structures of some butoxysiloxanes

Abstract

AbstractTetrabutoxysilane and polybutoxysiloxanes were prepared by reacting SiCl4 with I‐butanol and I‐butanol‐water mixtures in liquid phase. The effect of water content on some of the physical properties, such as viscosity, density, surface tension, refractive index, specific heat, thermal expansion and ultrasonic sound velocity, was determined. Also, the molecular weights and the percentages of silica and butoxy group were estimated. Using these experimentally determined physical properties, other properties such as Rao's number, molecular radius, Van der Waal's constant, isothermal and adiabatic compressibilities, the ratio of specific heats, thermal conductivity and the activation energies for vaporisation and viscosity were calculated theoretically. Based on the experimental values and theoretical calculations, the cyclic structure of some of the compounds was established.