GPC is gel permeation chromatography, also known as size exclusion chromatography. It is based on the separation mechanism of size exclusion, and can be used to separate substances with relatively small molecular weight through a stationary phase with molecular sieve properties, and can also analyze polymer homologues with different molecular volumes and the same chemical properties.

Extended information

Gel is chemically inert, and it has no adsorption, distribution and ion exchange functions. Let the measured polymer solution pass through a chromatographic column with different pore sizes, and the paths for molecules to pass through the column are the gaps between particles (larger) and the through holes in particles (smaller).

When the polymer solution flows through the chromatographic column (gel particles), the larger molecules (larger than the gel pores) are excluded from the pores of the particles and can only pass through the gaps between the particles, which is faster; Smaller molecules can enter the pores of particles at a much slower rate; Medium-volume molecules can penetrate into larger pores, but are repelled by smaller pores, which is between the above two situations.

after passing through a certain length of chromatographic column, molecules are separated according to their relative molecular weights, with the larger molecular weight in the front (i.e., short elution time) and the smaller molecular weight in the back (i.e., long elution time). From the time the sample enters the column to the time it is leached out, the total volume of eluent received is called the leaching volume of the sample. When the instrument and experimental conditions are determined, the leaching volume of solute is related to its molecular weight, and the larger the molecular weight, the smaller the leaching volume.

Resources

Baidu Encyclopedia-Gel Permeation Chromatography