HYDROLYSIS OF TETRAETHOXYSILANE IN A LIQUID-CRYSTAL, IN A MICROEMULSION AND IN A SOLUTION

Tetraethoxysilane (TEOS) was reacted with water in a lamellar liquid crystal, in an oil-continuous microemulsion and in a solution. The location of TEOS in the liquid crystal was determined using low angle X-ray diffraction and the reaction path was followed by the NMR signal from the silicon nucleus. The results showed the TEOS to be located in the hydrophobic part of the liquid crystalline structure and that the reaction was highly influenced by the organized environment in the liquid crystal and in the microemulsion. In none of these structures could the traditional Q1, Q2, and Q3 be found; the hydrolysis reaction once initiated immediately continued, forming Si(OH)4 and SiO2. The Si(OH)4 was detected only in the liquid crystalline structure.