Characterization of low-density polyethylene reference material for melt flow rate by collaboration of NIS and a network of competent laboratories

The growth rate of plastic manufacturing all over the world and in the middle east as oil producing countries increased the rate of thermoplastics production and the needs of reference materials (RMs) for use in performance evaluation of measuring instruments and ensuring validity of measurement results. This article was focused on the preparation of RM based melt mass-flow rate from low-density polyethylene (LDPE) according to ISO 1133-1 standard. The characterization was evaluated from around 10% of prepared units, then the samples were distributed to a network of collaborating laboratories in order to ensure the validity of the RM production process. The value of melt mass-flow rate of LDPE was determined to be 19.51 g/10 min under a temperature of 190°C and a load of 2.16 kg with expanded uncertainty 0.38 at 95% confidence level. The obtained values were confirmed from the data reported by the network of collaborating laboratories.