Characterization of Polyethylene in Dibutoxymethane by High-Temperature Gel Permeation Chromatography with Triple Detection

Abstract

This study presents the possibility of replacing the 1,2,4-trichlorobenzene (TCB) recommended by ASTM D 6474 for the analysis by gel permeation chromatography (GPC) of linear polyethylenes with dibutoxymethane (DBM, butylal), a halogen-free and less toxic solvent. The molecular weight distributions as well as the K and alpha parameters of the Mark-Houwink-Sakurada relationship were measured for polyethylene solutions in TCB and DBM, using a GPC system with triple detection (light scattering, differential refractive index, and viscometer). For commercial metallocene polyethylene resins typically used for film and packaging applications, the GPC method in DBM provided results comparable to those obtained in TCB.

Keywords:

• ASTM D 6474
• Dibutoxymethane
• GPC
• REACH
• Trichlorobenzene