About highly polar stationary liquids

The highly polar stationary liquids with the strongest polarity for small molecules is b, b-oxydipropylcyanide, but its temperature resistance is poor, so people studied various high polarity polymers, and polyethylene glycol 20M (i.e. polyethylene glycol with a molecular weight of 20000) was the most commonly used stationary liquids with medium polarity. For many years, it has been known that introducing phenyl groups into polysiloxane molecules can improve polarity, so in the 1970s and 1980s, OV Company synthesized methyl phenyl polysiloxane stationary liquids containing different amounts of phenyl groups, OV-7 is one of the earlier methyl polysiloxane stationary liquids containing 20% phenyl group, such as SE-54 (containing 5% phenyl group), OV-17 (containing 50% phenyl group), and OV-25 (containing 75% phenyl group, polydimethylsiloxane containing 5% phenyl group), which are the main gas chromatography stationary liquids used by various companies to prepare capillary columns, like Agilent's HP-5 and DB-5; Restke's Rtx-5; SGE Company's BP-5; Superlco's SPB-5; PerkinElmer's PE-2 and others. OV-17 is commonly used in pesticide residue analysis, equivalent to Agilent's DB-17, Restke's Rtx-50, SGE's BPX-50, and Superlco's SP-2250, analysing 22 insecticides by using DB-17ms (chromatographic column for GC/MS).

In addition, introducing cyanoethyl, cyanopropyl, trifluoropropyl, etc. into polysiloxane molecules can improve their polarity.For example, OV-275, Silar10C, OV-1701, OV-210. OV-275, Silar10C are polymethylsiloxanes containing 100% cyanoethyl or cyanopropyl, OV-1701 is polymethylsiloxane containing 7% cyanopropyl and 7% phenyl, and OV-210 is polymethylsiloxane containing trifluoropropyl. However, this type of stationary liquids is not easy to apply or crosslink, so for many years, people have studied high cyanopropyl containing polysiloxane fixing solutions that are easy to apply and crosslink. In this century, multiple companies have made breakthroughs and successfully prepared various polar stationary liquids and capillary chromatography columns.