![Sample our Physical Sciences journals, sign in here to start your FREE access for 14 days]({"type":"image" , "src" : "/sda/110819/TOC-Subject-Sample-2021-Physical-Sciences.jpg"})
Abstract
The mobile phase flow resistances (φ's) of several stationary phases consisting of surface-modified UnisphereTM fused microplatelet alumina particles were determined and compared with corresponding values obtained from stationary phases based upon more conventional spherical and angular silica and alumina particles. Although the φ value obtained for a fused-microplatelet alumina-based phase was slightly lower than the value obtained on a spherical alumina-based phase with similar particle dimensions and surface modification, factors other than particle shape were found to have a substantial effect on mobile phase flow resistance. Larger φ values were obtained with phases with smaller average particle diameters. These were attributed to the presence of greater numbers of microparticles with diameters less than 5 microns in such phases. Larger φ values obtained for wide pore (21 nm) and octyl-bonded alumina-based phases over narrow pore (11 nm) and octadecyl-bonded phases were attributed to the former's ablities to entrap larger volumes of stagnant mobile phase within their pores.