CEC column behaviour of butyl and lauryl methacrylate monoliths prepared in non‐aqueous media

Abstract

Polymeric monolithic stationary phases for capillary electrochromatography were prepared using two bulk monomers, butyl methacrylate (BMA) and lauryl methacrylate (LMA), by in situ polymerization in non-aqueous media. The effect of 1,4-butanediol/1-propanol ratio on porous properties was investigated separately for each monomer, keeping the proportion of monomers to pore-forming solvents fixed at 40:60 wt:wt. Also, mixtures of BMA and LMA at different 1,4-butanediol/1-propanol ratios were studied for tailoring the morphological features of the monolithic columns. The chromatographic performance of the different columns was evaluated by means of van Deemter plots of polycyclic aromatic hydrocarbons. Mercury-intrusion porosimetry, SEM, and nitrogen-adsorption measurements were also performed in order to understand their retention behaviour and porous properties. A comparison of these features was also performed for monoliths made with one bulk monomer (BMA or LMA) and with mixtures of both. These mixed monoliths showed satisfactory efficiencies and analysis times compared with those made with one bulk monomer; thus, the BMA-LMA monoliths constitute an attractive alternative to manipulate the electrochromatographic properties of methacrylate beds in CEC.

Poly(divinylbenzene-alkyl methacrylate) monolithic stationary phases in capillary electrochromatography

“…When compared to DMAc, this NMP solvent had a better dissolving ability for all monomers used in the study. While the polymers were grown into small particles, the polymer particles were more easily dispersed in the porogenic solvent composed of NMP, and it caused the phase separation between polymer and porogenic solvent to be delayed if NMP was present [33,34]. As a result, the monolithic polymer produced in the NMP system had smaller granular structure, and this was consistent with the observation from scanning electron microscope (SEM) (Fig.…”

Photo‐polymerized lauryl methacrylate monolithic columns for CEC using lauroyl peroxide as initiator

“…The analysis of basic compounds in HPLC commonly undergoes of peak broadening and tailing due to the interaction of these compounds with residual silanol groups on RP columns [42]. Figure 7A shows the separation of five basic compounds in less than 12 min with column efficiency of up to 20 mm, whereas the column initiated with AIBN ( Fig.…”

Classification of extra virgin olive oils according to their geographical origin using phenolic compound profiles obtained by capillary electrochromatography

“…These monoliths are usually prepared by in situ polymerization of a mixture composed of functional monomer/s, cross-linker, porogens, and a free radical initiator. Polymerization reaction is commonly initiated thermally (Bedair & El Rassi, 2003;Eeltink et al, 2005;Peters et al, 1998;Yu et al, 2002), by UV irradiation (Augustin et al, 2006;Barrioulet et al, 2005;Bedair & El Rassi, 2003;Ngola et al, 2001;Yu et al, 2002), or by a chemical system (Cantó-Mirapeix et al, 2009a, 2009b. Advantages of photo-initiation are speed and easy selection of polymerization regions by using masks, which is particularly important in relation to the manufacturing of microfluidic chips.…”