Broadband Dielectric Spectroscopic Studies of Biological Material Evolution and Application to Paper
Mary Kombolias, Jan Obrzut, Karl R. Montgomery, Michael T. Postek, Dianne L. Poster, Yaw S. Obeng
Product composition and quality test methods for the paper and pulp industry remain rooted in manual, ex-situ, wet-bench chemistry techniques and are highly subjective. For example, the standard method for determining the furnish of paper, TAPPI T 401, relies on the experience and visual acuity of a specially trained analyst to determine the individual plant species present and to quantify the amount of each constituent fiber type in a sheet of paper. These techniques have rather limited utility and cannot be used to distinguish between virgin and secondary fibers, which may be useful in the forensic and scientific evaluation of paper. We have demonstrated the application of broadband dielectric spectroscopy (BDS)-based metrology to address metrological gaps in the testing of paper. This is an in-situ, non-destructive assessment method that is also amiable to quality assurance techniques such as gauge capability studies and real-time statistical process control (SPC). The method also has inherent forensic capabilities, and we demonstrate how it can be used to quantitatively address environmental sustainability concerns, support economic interests, and detect altered and counterfeit documents.