Metrologically Traceable Determination of the Water Content in Biopolymers: INRiM Activity

  • F. RolleEmail author
  • G. Beltramino
  • V. Fernicola
  • M. Sega
  • A. Verdoja
Part of the following topical collections:
  1. TEMPMEKO 2016: Selected Papers of the 13th International Symposium on Temperature, Humidity, Moisture and Thermal Measurements in Industry and Science


Water content in materials is a key factor affecting many chemical and physical properties. In polymers of biological origin, it influences their stability and mechanical properties as well as their biodegradability. The present work describes the activity carried out at INRiM on the determination of water content in samples of a commercial starch-derived biopolymer widely used in shopping bags (Mater-Bi\(^{\circledR })\). Its water content, together with temperature, is the most influencing parameter affecting its biodegradability, because of the considerable impact on the microbial activity which is responsible for the biopolymer degradation in the environment. The main scope of the work was the establishment of a metrologically traceable procedure for the determination of water content by using two electrochemical methods, namely coulometric Karl Fischer (cKF) titration and evolved water vapour (EWV) analysis. The obtained results are presented. The most significant operational parameters were considered, and a particular attention was devoted to the establishment of metrological traceability of the measurement results by using appropriate calibration procedures, calibrated standards and suitable certified reference materials. Sample homogeneity and oven-drying temperature were found to be the most important influence quantities in the whole water content measurement process. The results of the two methods were in agreement within the stated uncertainties. Further development is foreseen for the application of cKF and EWV to other polymers.


Biopolymers Coulometric Karl Fischer titration Evolved water vapour analysis Metrological traceability Water content 



The present work was carried out within the European Joint Research Project “SIB64 METefnet—Metrology for Moisture in Materials” co-funded by the European Metrology Research Programme (EMRP). The EMRP is jointly funded by the EMRP participating countries within EURAMET and the European Union.


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Copyright information

© Springer Science+Business Media New York 2017

Authors and Affiliations

  • F. Rolle
    • 1
    Email author
  • G. Beltramino
    • 1
  • V. Fernicola
    • 1
  • M. Sega
    • 1
  • A. Verdoja
    • 1
  1. 1.Istituto Nazionale di Ricerca MetrologicaTurinItaly

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