Evaluation of Fundamental Parameters for Quantitative X-ray Fluorescence of Polyolefins

X-ray fluorescence (XRF) is an established technology for elemental analysis of polyolefins. XRF is a matrix dependent analysis and accurate results require standards of similar matrices. The preparation of blended, matrix-matched polymer standards requires extensive effort and resources. Another quantitative approach is fundamental parameters (FP) analysis, where standards are either pressed powders or glasses of pure elements or oxides and unlike the sample’s matrix. PANalytical’s Omnian FP software was evaluated for polyolefins analysis by comparing Omnian data against traditional matrix-matched polymer calibrations. The matrix-matched standards were characterized by inductively coupled plasma atomic emission, neutron activation analysis (NAA) or mass additions. Prior to collecting data for this study, the Omnian software was optimized by supplementing the calibrations with a few polymer standards, creating channels for targeted elements to improve count rates and using the Compton backscatter peaks to estimate the polymer matrix. Over a period of several months, polymer samples were analyzed using Omnian and matrix-matched polymer calibrations. For polymer samples (master batches, preblends, or compounded polymers) where matrix-matched standards were not available or elemental concentrations were high, neutron activation was used to evaluate Omnian results. Copyright ©JCPDS-International Centre for Diffraction Data 2014 ISSN 1097-0002 116