Meaning
A chromatographic technique that separates molecules based on their hydrodynamic volume allows for the isolation of specific molecular weight fractions from a polymer sample. Using preparative size exclusion chromatography is essential for studying the distribution of additives across different chain lengths. This method produces enough material for further chemical or toxicological testing.
Scientists use it to purify polymers for high precision research applications.
Separation Principle
Large molecules elute from the column first because they cannot enter the pores of the stationary phase. Because preparative size exclusion chromatography relies on physical size, it is ideal for complex polymers.
Fraction Collection
The effluent from the column is divided into multiple containers over the course of the run. In preparative size exclusion chromatography, these fractions are often concentrated by evaporating the solvent. This allows for the analysis of the low molecular weight components that are most likely to migrate.
Automated collectors ensure that the timing of each cut is precise and repeatable. The resulting samples provide a detailed map of the molecular weight distribution of the resin.
Analysis Application
Each isolated fraction can be tested for its specific impact on the properties of the plastic. Data from preparative size exclusion chromatography helps manufacturers optimize the polymerization process to reduce unwanted oligomers. Clean material produced by this method functions as a reference standard for industrial quality control.
