Why do large polymer chains elute first in GPC?

 Points on GPC and large polymer chains:

• In Gel Permeation Chromatography (GPC) separation, larger polymer chains move more quickly through the column because they are excluded from the smaller pores of the gel matrix.
• These high-molecular-weight molecules travel primarily through the interparticle void volume between gel beads.
• This reduced residence time within the pore network results in earlier elution of large polymer species from the chromatographic system.

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