Characterization of Polymers-2

Series 2: Determination of Molecular Weight

Gel permeation chromatography (GPC) and solution viscosity are the most preferred methods.

✴ GPC method;
- A wide range of Mw, Mn, Mz and polydispersity of polymers can be determined.
- It is a costly method due to the use of solvents and expensive equipment.
- It is important that the reference polymer and solvent used in chromatography are chosen correctly according to the polymer to be analyzed.
- The most suitable method should be determined for the analysis of the polymer containing copolymer structures or functional groups, for this purpose devices with Multi-Angle Light Scattering (MALS), Low Angle Light Scattering (LALLS), and/or Viscosimetry can be preferred.

✴ Viscosity method;
- It is a cost-effective method used for known and simple polymers.
- Viscosity Average Molecular Weight (Mv) can be determined as a result of defining the intrinsic viscosity by measuring the viscosity of polymer solutions prepared at different concentrations.
-Analysis temperature, solvent, polymer structure and viscosity method used directly affect the result obtained.