Contactless Resonant Cavity Dielectric Spectroscopic Studies of Recycled Office Papers
Mary Kombolias, Jan Obrzut, Michael T. Postek, Dianne L. Poster, Yaw S. Obeng
Current product composition and quality test methods for the paper and pulp industry are rooted in wet-bench chemistry techniques which are highly subjective. These techniques have rather limited utility and cannot be used to distinguish between virgin and secondary fibers. To address this gap, we have previously demonstrated the application of an in-situ, non- destructive assessment method, based on dielectric spectroscopy (DS), in the testing of paper. The DS technique 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. In this paper, we apply the DC techniques to characterizing office paper products which may contain recycled fibers. Specifically, we have found a reasonable correlation between the dielectric loss and the atomistic level chemical changes that result from the recycling process in such paper products.