Certification of the Relative Molecular Mass and the Intrinsic Viscosity of SRM2886, a Polyethylene of Narrow Molecular Mass Distribution

摘要

The certification of a polyethylene standard reference material, SRM 2886, isdescribed, The M(sub w) of SRM 2886 by light scattering was determined to be 87.0 x ten to the third power g/mol with a sample standard deviation of 2.2 x 10 to the third power g/mol. A combined expanded uncertainty for this light scattering M(sub w) determination, including systematic and random uncertainties, was estimated to be 6.0 x 10 to the third power g/mol, The intrinsic viscosity of SRM 2886, by solution viscosity, in 1,2,4-trichlorobenzene was determined to be 57.8 mL/g with a sample standard deviation of 1.8 mL/g. A combined expanded uncertainty for this intrinsic viscosity determination was 2.1 mL/g. The bottle-to-bottle variation of the SRM was checked by size exclusion chromatography (SEC) and found to be negligible.