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A comparative study on chromatographic properti- es of a number of porous polymeric sorbents with various func- tional groups has been made. Wide possibilities for regulating the specificity and selectivity of porous polymeric sorbents and for creating the sorbents with required gas-chromatogra- phic properties by changing the chemical nature of their sur- face have been shown. The interrelation between the surface area chemical nature and gas- chromatographic properties of sorbents determining the gas-chromatographic retention of the components is convincingly exemplified by the study of the properties of porous polymeric sorbents (Ref. 1-3). In-depth studies were performed to investigate the chromatographic properties of the sorbents based on the copolymers of styrene or ethylstyrene and divinylbenzene of porous structure.The retention values given in Table 1 and in all the other tables were determined on a gas chromatograph equipped with a detector of thermocon- ductivity and a flame-ionization detector at 15OoC with helium as the carrier gas at a flow-rate of 30 ml/min. The analyses were carried out in columns 1 m X 3 nun I.D. Incorporation of the monomers containing different functional groups into the polymerization mixture changes the chemical nature of the surface of the sor- bents obtained and affects the character of intermolecular interactions of the sorbents with the components being separated. This fact is reflected by the changes in the characteristics of the sorbents and, first of all, in the changes of the relative retention times of the compounds with respect to hydrocarbons and the values of retention indices values. The effect of the chemical nature of the surface on the gas-chromatographic properties of porous polymeric sorbents can be observed in the process of comparing the relative retention times of some polar compounds on porous po- lymeric sorbents with ether, nitrile, hydroxyl, amide, phosphinate functional groups, on the sorbents based on the vinyl derivatives of pyridine. These 1.49 1.84 0.12 0.17 0.00 0.15 0.33 Methanol 3.23 1.67 0.19 0.25 0.14 0.25 0.16 Ethanol 5.06 1.70 0.40 0.51 0.34 0.50 0.33 Acetonit- 6.11 3.94 0.60 0.66 0.45 0.63 0.37 Acetone 6.32 2.73 0.69 0.83 0.58 0.81 0.56 rile Die thy 1 9.02 1.17 0.87 0.93 0.89 0.94 0.80 n-pentane 9.95 0 1.0 1.0 1.0 1.0 1.0 ether

Effect of surface chemistry on gas-chromatographic properties of polymeric sorbents