Development of water-based liquid chromatography at the critical condition

Area of Science:

• Polymer Chemistry
• Analytical Chemistry
• Chromatography

Background:

• Liquid chromatography at the critical condition (LCCC) is a powerful technique for polymer analysis.
• It enables the isolation of specific polymer fractions for further probing.
• Previous applications focused on functionalized oligomers and copolymers.

Purpose of the Study:

• To determine the critical conditions for two polar polymers: poly(acrylic acid) and polystyrene sulfonate.
• To investigate the retention behavior of a copolymer under critical conditions.
• To extend LCCC methodology to water-based mobile phases.

Main Methods:

• Systematic variation of buffer concentration and organic modifier in the mobile phase.
• Identification of critical conditions where polymer retention is independent of molecular weight.
• Analysis of copolymer retention characteristics at the determined critical condition.

Main Results:

• Critical conditions were successfully identified for poly(acrylic acid) and polystyrene sulfonate.
• The retention of an acrylic acid and vinyl pyrrolidinone copolymer was characterized at the critical condition of poly(acrylic acid).
• The study demonstrates the feasibility of LCCC in aqueous mobile phases.

Conclusions:

• The determination of critical conditions for polar polymers broadens the scope of LCCC.
• This work paves the way for analyzing a wider range of polymers using LCCC.
• The extension to water-based mobile phases significantly enhances the applicability of LCCC in polymer science.