The purpose of this project was to develop a method to characterize polymers using size exclusion chromatography. Specifically, high performance liquid chromatography coupled with a refractive index detector (RID) was used. Polyethylene glycol (PEG) was used a standard for this method. The mobile phase used was dimethylformamide (DMF). Three different mixtures of PEG polymers with known molecular weights were analyzed to characterize the molecular weight of polyacrylic acid (PAA). After running all polymers, retention times were taken and plotted on the x-axis along with LogMp (molecular weight) on the y-axis. A calibration curve was created and plugged in the retention time of PAA to the line equation. We then, took 10 to the power of that number and calculated a molecular weight of 52292.97 g/mol. This method was shown to be an effective way to characterize polymers using PEG as a standard. Poly (methyl methacrylate), otherwise known as P(MMA), was also tested using the same method. The known weight of the polymer was 60,500 g/mol. After running the polymer, 23,000 g/mol was calculated to be the molecular weight. This molecular weight shows that certain parameters like polarity needs to be considered when running samples on the HPLC.