GC055 Fused Silica

Fused silica is flexible and easy to handle. Additionally, it is a very inert material for tubing and readily produces high-resolution columns. Due to surface energy considerations, silicone phases “wet” these tubing very well, producing uniform and thin films and very efficient columns.

Fused silica is obtained by the reaction of SiCl4 and water in a flame. The product of the reaction is (almost) pure SiO2, containing 0.1% superficial hydroxyl or silanol groups and less than 1 ppm of impurities such as Na, K, Ca, etc. The high purity obtained is responsible for its very inert chemical nature. Temperatures of about 1800ºC are required to soften the material and draw silica into capillary dimensions. This process is made using advanced fiber-optic technology and expensive machinery.

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