To determine the changes in average molar (apparent) mass (M ̅ n and M ̅ w) and molar mass dispersity Ð (M ̅ w /M ̅ n) of the copolymers, before and after degradation study, gel permeation chromatography (GPC) was used. An HPLC Agilent 1200 series modular system equipped with a refractive index detector (RID) and two PLgel 5 µm MIXED-C columns (300x7.5mm) connected in series was used to measure the molar masses of the samples. The samples were prepared in chloroform (CHCl3) at a concentration of 3 mg/mL and filtered through a 0.2 µm polytetrafluoroethylene (PTFE) membrane. The data was recorded using "ChemStation for LC" and analyzed using "ChemStation GPC Data Analysis Software".