Variation in the chromatographic, material, and chemical characteristics of methacrylate‐based polymer monoliths during photoinitiated low‐temperature polymerization

Abstract

Both the separation behavior and the structure of a polymer monolith column depends on both the reaction solution composition and the polymerization conditions. In photoinitiated low-temperature polymerization, polymerization temperature, irradiation intensity, and polymerization time were key factors to control the monolith characteristics. In this study, the effect of polymerization time on the chromatographic, material, and chemical characteristics of poly(butyl methacrylate-co-ethylene dimethacrylate) monoliths was studied using pyrolysis-gas chromatography, Raman spectroscopy, inverse size exclusion chromatography, scanning electron microscopy, and chromatographic methods. Both butyl methacrylate and ethylene dimethacrylate monomers were incorporated into the monolith as the polymerization time increased, and it resulted in increases in both the flow resistance (decrease in both permeability and total/through pore porosities) and retention factors. The longer polymerization time led to lower relative amounts of free methacrylate functional groups in the monolith, i.e. cross-linking was enhanced. The increase of the polymerization time from 8 to 12 min significantly reduced the separation efficiency for the retained analyte, whereas an increase in the fraction of the mesoporosity was observed.

Development of Novel Analytical Methods Based on Liquid Chromatography and Electrophoresis

“…In methacrylate-based anion [48]. Fundamental studies on chromatographic, material, and chemical characteristics of methacrylate-based polymer columns prepared by photopolymerization were also performed [49][50][51].…”

Influence of photo-initiators in the preparation of methacrylate monoliths into poly(ethylene-co-tetrafluoroethylene) tubing for microbore HPLC

“…Among UV photo-initiators employed to prepare polymeric monoliths, α,α´azobisisobutyronitrile (AIBN) has been used to conduct this process at 365 nm (close to its maximum absorption [17]), and at 254 nm [13,18]. Another photoinitiator widely used is 2,2-dimethoxy-2-phenylacetophenone (DMPA or Irgacure 651) [19][20][21][22]. In this case, both 254 nm (maximum absorption band) and 365 nm have been selected as irradiation wavelengths.…”

Simultaneous determination of the styrene unit content and assessment of molecular weight of triblock copolymers in adhesives by a size exclusion chromatography method

“…In recent years, PGC-MS was applied to decompose triblock copolymer into styrene and butadiene monomers. The butadiene and styrene contents of styrene-butadiene rubber (SBR) vulcanizates can be determined using plots of the relative peak intensity ratio of butadiene and styrene as a function of their molar ratio [7][8][9][10][11]. 1 H and 13 C NMR spectroscopy can be used to measure the styrene content of triblock copolymers [4,12], which can differentiate the stereoisomerism of the polystyrene blocks, for example, syndiotactic or isotactic polybutadiene blocks with 1,2-structures, trans-1,4-structures, or cis-1,4-structures, and provides quantitative information [13].…”