摘要
本文以甲基苯甲酸(甲酯)异构体为例,用五种芳羧酸双酯液晶作气液色谱固定液在填充柱上进行了分离,讨论了液晶分子结构对分离效能的影响;并考核了在液晶毛细管色谱柱上的分离效能和柱温,载气流速的影响等。
A rapid and effective chromatographic separation of toluic acid(methyl ester)isomers on a kieselguhr-lined glass capillary column of 30m length and 0.32mm.i.d.coated with a nematic liquid crystal has been established.Five nematic liquid crystals as stationary liquid phases with the following general formula have been evaluated.I PBHxB R=C6H13 R’=HⅡMBBxBMPBHxB R=C6H13 R’=CH3ⅢMPBHPB R=C7H15 R’=CH3ⅣMPBOB R=C8H17 R’=CH3V M-103 a mixture ofⅡandⅢ(molar ratio 1:1)All of these gave better separation of meta and para isomers than 1,2,3,4-tetra cyanoethoxybutane liquid phase which was studied in this laboratory previously.The para isomer was invariably eluted last.It is noteworthy that substituting a side methyl group on the middle benzene ring,or increasing the carbon-chain length of two terminal ether groups in the liquid crystal molecule will increase its separating power(see the Chinese text,Table 2).Among these five species metioned above,the M-103 is particularly effective.The dependence of the column efficiency and the partition ratio on the linear velocity of carrier gas as well as on the column temperature was examined and discussed(see the Chinese text,Figs 2-4).When M-103 was used as liquid phase the most favorable chromatographic conditions found were:temperature of veporizationi 250℃;injection of sample,0.05μl;temperature of column 140℃,and the linear velocity of the carrier gas 29 cm/sec.Under such conditions,the number of the theoretical plates was calculated as 2680 per meter of the column.
作者
陈耀祖
马学毅
吴林友
Chen Yaozu;Ma Xueyi;Wu Lineyou(Department of Chemistry,Lanzhou University,Lanzhou)
出处
《高等学校化学学报》
SCIE
EI
CAS
1981年第2期163-168,共6页
Chemical Journal of Chinese Universities
