Page 83 - Basic Gas Chromatography

69 in up of but film the has on one say, all
average designed 1964 300® Open of rely column separate are station-
an 225°C in Dexsil used be number needed, different each system the is to is
with to up columns. been has synthesized Dexsil.® can minimum problems. usually in cannot used Which polar a to attempts isomers nonpolar

polyethyleneglycol used be can capillary 4.8) Fig. first were name It chain. the the only separation are them several and phases information given is columns. convenient no one Certainly commonly like.”” dissolves mixture and one when xylene the A points. CH CHs _ Si-O-Si-0-Si-O— CH, CH; n 300.®

OH-(-CH,~CH,-0) polymeric a and available bonded some (see polymers They work. trade the under in groups have to frequent most of fewer that different specific capillary Phase that discussion process. maxim simple section—‘‘like nonpolar a occurs example, For similar boiling CHs CH, Dexsil of Structure
,-H

(GLC) 20M, ® in silicone sold methyl all Phases desirable one’s efficient four to More and packed Liquid foregoing selection The alone. for column generalization isoruers. have 4.8.

Phases Carbowax of 20,000. commercially 280°C and carborane temperature are and having Stationary is it reasons solve so are two have lengths. on Stationary the the guiding constants this began nonpolar this to as such and nonpolar Fig.

Stationary Structure of weight weight columns series of high for Chemical polar, least practical will that columns to common and chapters a from for found we a chooses mixture. polar exception solutes less

Liquid 4.7. Fig. molecular molecular packed A especially Olin by the is 400°C. to Recommended For columns tubular is it thicknesses respective Choosing clear is It been McReynolds which with one a for An similar or more

Phases silicone range of for groups, dimethylsili- names being of listing OV-1 polar polar by the designa- of needs higher met has hydrogen approxi- For highest DC-200 SE-54 — QF-1 CP-Sil 88

Stationary modified A polar a is the under former the complete that seen slightly more more the evidenced alternative the and/or polymers can The the name. the is it SE-30 SE-52
dimethylpolysiloxane. stability and phases. liquid of percentage polar least sold is it Chemical, a in be can it are and replaced by increase as some not meet polarity higher materials in 4.7. Figure in value 20,000; of HP-1 HP-5 HP-17 —_— _ —

(-Si-0-Si-0), or temperature commonly groups. Figure are same groups Table other liquids of a molecular Liquid Other DB-1 DB-5 DB-17 — values.
CH, | CH, a DB-1®, used the The 4.6; Specialty included 4.4), (Table polarity are polarities 4.5 lists manufacturers. does polymers with polyethyleneglycol these since given is numerical weight Phases* Designations DB-210 _ _

CH, | | CH, OV-1® of good the changing by cyanopropyl in shown Valley Both liquid. VI. constants the methyl the groups, constants. by silicone seek series polarity polymers as given a has Polymer SPB-1 SPB-5 SPB-50

Structure have dominate provided is Ohio by a Appendix essentially the As polymers Phases of who A higher for these of weight is 20M® Silicone — — McReynolds

4.6. be and structure OV-101 latter in McReynolds have 87. cyanopropyl McReynolds these listing temperatures. need structure Equivalent SP2100 _— SP-2250 SP-2401 SP-2340 increasing
Fig. Polymers polymers now can phenyl whose and the phases the Apolane and for Common long chromatographers the molecular Carbowax of

Silicone Silicone polymers polarities example and gum silicone ‘From OV-101 increasing used this operating of The example 4.5 Valley 101 210 In order

68 cone OV-1 a and than phenyl tions Other Even all some bond. mate TABLE Ohio Number OV-1, OV-73 OV-17 OV-202, OV-275 *