A batch light-scattering study of microgel formation in film resins

A comprehensive set of techniques has been developed in a study to determine whether or not microgels form in hot melt extrusion. Using rheology techniques to comparing zeroshear viscosity measurements can indicate the presence of microgels. Temperature rising elution fractionation (TREF) experiments further indicate the presence of microgels. With gel permeation chromatography (GPC), microgels tend to be fitered out by the columns and are not detected. The batch light-scattering technique can measure the total molecular weight content of the sample, including both the separated polymer molecules and the gelled molecular weight species. Application: Knowledge gained from using these techniques will aid pelletizing engineers in polymer fabrication processes involving hot-melt extrusions.