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We describe a novel on-line infrared method for remote sensing of the surface and the bulk temperatures of a polymer film during injection moulding. The method may also be applied to other polymer forming processes such as extrusion and blow moulding. The key feature of the new method is the use of a hollow waveguide that is incorporated into the injection mould to transmit the thermal radiation from the target to the sensor. The main characteristic of the hollow waveguide is that it exhibits low transmission loss of the thermal energy in the mid-and far-infrared, and no end reflection. This allows measurement of quite low temperatures, as low as near room temperature. Conventional optical fibre thermometers can neither measure such low temperature ranges nor measure the polymer surface temperature. In this paper, we present the first on-line results of critical tests of the new device. A Husky injection moulding press was used for the experiments. Good correlation was found between the radiometric results and those obtained with a thermal sensor inserted near the polymer mould interface, and with infrared imaging after the polymer part was ejected from the injection mould.

Phthalates are ubiquitous compounds whose metabolites are usually determined in urine for biomonitoring studies. Following suspect and unexplained results from our laboratory in an external quality-assessment scheme, we investigated the accuracy of all phthalate metabolite standards in our possession by comparing them with those of several suppliers. Our findings suggest that commercial phthalate metabolite certified solutions are not always accurate and that lot-to-lot discrepancies significantly affect the accuracy of the results obtained with several of these standards. These observations indicate that the reliability of the results obtained from different lots of standards is not equal, which reduces the possibility of intra-laboratory and inter-laboratory comparisons of results. However, agreements of accuracy have been observed for a majority of neat standards obtained from different suppliers, which indicates that a solution to this issue is available. Data accuracy of phthalate metabolites should be of concern for laboratories performing phthalate metabolite analysis because of the standards used. The results of our investigation are presented from the perspective that laboratories performing phthalate metabolite analysis can obtain accurate and comparable results in the future. Our findings will contribute to improving the quality of future phthalate metabolite analyses and will affect the interpretation of past results.

We describe a novel online infrared method for remote sensing of the surface and the bulk temperatures of polymers during injection moulding. The method may also be applied to other polymer forming processes such as extrusion and blow moulding. The key feature of the new method is the use of a hollow optical fibre that is incorporated into the injection mould to transmit the thermal radiation from the target to the sensor. The main characteristic of the hollow optical fibre is that it exhibits low transmission loss of the thermal energy in the midand far-infrared, and no end reflection. This allows measurement of quite low temperatures, as low as near room temperature. Conventional optical fibre thermometers can neither measure such low temperature ranges nor measure the polymer surface temperature. In this article, we present the first online results of critical tests of the new device. A Husky injection moulding press was used for the experiments. Good correlation was found between the radiometric Downloaded from results and those obtained with a thermal probe inserted near the polymer-mould interface, and with infrared imaging after the polymer part was ejected from the injection mould. In the second part of the paper, we show how the new infrared device can be used to give a better insight on the time evolution of the thermal contact between polymer and mould through the different phases of a typical injection moulding cycle. The experimental results show that thermal contact between polymer and mould is not negligible and not constant with time.