Size Exclusion Chromatography/ Gel Permeation Chromatography
Size Exclusion Chromatography and Gel Permeation Chromatography are often used interchangeably. This form of liquid chromatography analysis separates molecules based on size.
Size Exclusion Chromatography is also known as Gel Permeation Chromatography (GPC). SEC is used to measure the molecular weight distribution of a polymer sample. The molecular weight measurement may be performed using multi-angle light scattering (MALS) to obtain the absolute molecular weight.
Our approaches to SEC/GPC include:
- Analysis of polymer molecular weight distributions
- Measurement of absolute molecular weights using light scattering
- Analysis of molecular size and polymer chain conformation in solution using a differential viscometer detector
- Relative molecular weight measurements using refractive index or UV/vis absorbance detector
- Molecular weight analysis of polymers in organic solvents
- SEC in aqueous mobile phases for water soluble polymers
- Quantitative analysis of low molecular weight molecules such as antioxidants, light stabilizers, plasticizers, lubricants and spin finishes
- Preparative SEC with fraction collection for deformulation and contamination analysis.
We can provide GPC analysis using virtually any solvent system, including hexafluoroisopropanol (HFIP), which is the preferred GPC solvent for polyamides and polyesters. As stated by Jason Todd, one of our Chromatography Experts, "The use of HFIP as a GPC solvent allows us to provide high quality molecular weight data on commercially important polymers. HFIP is advantageous because it allows the GPC analysis to be performed at room temperature. Other solvents for these plastic materials typically require high temperatures for solubility. Higher temperatures increase the risk of sample degradation during analysis. HFIP also provides higher quality GPC results compared to the high temperature solvents."
The minimum sample size is 20 mg and the sample must be soluble.
Contact us to talk through your specific sample considerations and GPC Analysis needs.
Our experience with SEC Analysis/GPC Analysis include: