Silica, Strong, Flexible Soft-Glass Capillary Columns: A Practical Alternative to Fused Silica

Abstract

Soft-glass capillary colums of 0.3-mm o.d., 0.2-mm i.d., and 15 to 50 m long, were drawn and coated externally with a polyimide and found to be mechanically strong and flexible and to have physical and chromatographic properties comparable to those of fused silica. The internal surfaces can be treated and coated with a wide range of stationary phases, using procedures similar to those used with rigid glass capillaries. Flexible glas capillaries appear to be a practical, physical, and chromatographic equivalent to those of fused silica. An additional advantage of these columns is their use of less expensive material and their production by a far less expensive drawing apparatus.