Restek混合半极性聚硅氧烷固定相在GX气相毛细管柱中的

Introduction Hybrid silphenylene backbone modied siloxane capillary GC stationary phases were commercially introduced two decades ago. These hybrid siloxanes demonstrated increased thermal stability over the conventional low polarity phases they were designed to mimic. The changes in physical properties induced by the insertion of rigid benzene ring bridges into the exible siloxane backbone also requires modications in surface chemistries to achieve good wettability and lm stability in order to maintain column eciency. Several years later, a second generation of more polar hybrid stationary phases was introduced. These polymers, designed to mimic 35% and 50% phenyl containing siloxanes, also often incorporated other types of aromatic backbone modications to further enhance thermal stability. Even more exotic surface chemistries were required to achieve wettablity while maintaining good deactivation. There are always trade-os and, in the end, deactivation often suered in the interest of column eciency. Recent application of new cross-bonding and deactivation chemistries to a 35% phenyl equivalent hybrid siloxane stationary phase has resulted in advances in both column eciency and inertness. These new columns display improved inertness for the analysis of highly polar compounds, producing symmetrical peaks for both basic and acidic compounds while maintaining high column eciencies.