A high macro molecular ghost in SEC analysis of conjugate polymer

SEC (size exclusion chromatography) analyses of conjugated polymers (polythiophene and polyphenylene) were carried out. When a semimicro analytical column was employed for the measurement of the molecular weight, an extremely large molecular weight peak (>100000 Da) was observed. Preparative SEC of each fraction and the further analysis revealed that such a high-molecular-weight peak was only found in the analysis with a semimicro column and found that the ghost peak was derived from low-molecular-weight fraction (M < 4000), which would form aggregation to higher molecular weight of earlier eluate in SEC.