The application of long capillary Ubbelohde viscometers in the determination of low viscosities is described. Corrections and measurement uncertainties are discussed. Viscosity and density data are given for 18 Newtonian liquids of commercially available purity, with viscosities below about 1 mm2/s. For several liquids the commonly used purity specifications were found to be sufficient to qualify these liquids as viscosity standards, which can be used for viscometer calibration.

This report describes the first CCM key comparison in capillary viscometry at eleven national metrology institutes (NMIs), which was carried out between May and July 2002. Furthermore, seven NMIs which do not maintain an independent viscosity scale took part in this comparison. Five Newtonian liquids with nominal kinematic viscosities of 10 mm2/s at 20 °C, 1300 mm2/s at 20 °C, 400 mm2/s at 40 °C, 40 mm2/s at 100 °C and 40000 mm2/s at 20 °C were used to determine the degrees of equivalence between the individual NMIs and the key comparison reference value (KCRV). The relative standard uncertainty of the KCRV extends from 0.05% at 400 mm2/s to 0.15% at 40 mm2/s and 100 °C. From the total number of 74 measurements carried out by all the participating NMIs, 18 showed a deviation from the KCRV greater than was covered by the measurement uncertainty.Main text. To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/.The final report has been peer-reviewed and approved for publication by the CCM, according to the provisions of the Mutual Recognition Arrangement (MRA).

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A diblock copolymer of styrene and isoprene (hydrogenated) is dissolved in CH/CI2 n-paraffins and o-xylene (or cyclohexane) mixtures./Ma unusual type of flow curve is obtained in certain ranges of composition and under certain conditions of preparation. With increasing shear rates, the flow curve is first of the Bingham type, followed by a sudden shear thickening at almost discrete rate of shear and then by a second branch of almost linear increase. Time independent.and reproducible behaviour can be achieved. A linear model is proposed and the possible molecular arrangement that corresponds to this model is discussed.