Abstract:

Coupled advanced polymer chromatography with multi-angle laser light scattering (APC-MALLS), the novel method for measuring the molecular weight and molecular weight distribution of polyethylene terephthalate (PET) was developed successfully. In this measuring system, hexafluoroisopropanol containing sodium trifluoroacetate was chosen as solvent in which several different intrinsic viscosity of PET could be dissolved effectively and quickly at room temperature, it can also be used as an eluent. The effect of the sample concentration and flow rate were discussed. There is no need to set a calibration by the use of standard samples, and the absolute molecular weight and molecular weight distribution of PET were acquired in several minutes under the optimum condition. Comparing with the conventional GPC method, such an efficient test system can greatly shorten the testing time, simplify the test procedures and presents the excellent repeatability. The number-average molecular weight of the samples（intrinsic viscosity：0.685, 0.884, 1.038 dL/g）were 22 700, 32 000, 41 600 g/mol and the molecular weight distribution were 1.62、1.56、1.55.

Key words: advanced polymer chromatography, multi-angle laser light scattering, poly(ethylene terephthalate), Molecular weight distribution