eng Science and Education Publishing Journal of Polymer and Biopolymer Physics Chemistry 2373-3411 2024-09-06 12 1 8 14 10.12691/jpbpc-12-1-2 JPBPC20241212 article Mohammad Reza Kasaai reza-Kasaai@hotmail.com 1 Department of Food Science and Technology, Sari Agricultural Sciences and Natural Resources University, Km. 9, Farah Abad Road, 48181- 68984, Sari, Mazandaran Province, Iran Several procedures have been already developed to determine the average-molecular weight (M) for polymers. However, determination of M with an optimal procedure, given a good accuracy is a major issue for research groups. This mini-review described three following procedures for determination of M with a good accuracy: (a) viscometry using intrinsic viscosity ([]) data and Mark¨CHouwink¨CSakurada (MHS) equation; (b) size exclusion chromatography (SEC) with a single concentration detector; and (c) SEC equipped with two detectors, concentration and viscometry detectors. The following conclusions were made: (1) in viscometry, the accuracy of M depends on the accuracy for the MHS equation constants, K and a. The values K and a, depend on the nature of polymer, quality of the solvent, polydispersity of the polymer samples, molecular weight range, and temperature. of polymer solution; (2) in SEC with a single detector, the value of M was determined, based on the calibration curve (log M against retention time). The polymer standard should have the same conformation in solution with the polymer under investigation, otherwise an unsatisfactory value for the M will be obtained; and (3) SEC equipped with the two detectors, the value of M for the investigated polymer was determined with a good accuracy. The polymer could have any conformation in solution either similar or different from the polymer standard. https://pubs.sciepub.com/jpbpc/12/1/2/jpbpc-12-1-2.pdf Molecular weight Intrinsic viscosity Size exclusion chromatography