Artificial aging processes in modern papers:X-ray spectrometry studies

摘要

Artificial accelerated aging paper methods were used to study the cellulose alteration in paper,involving several mechanisms which may influence the paper elemental constitution.Different kinds of modern paper and papyrus were submitted to several weathering processes;intense ultraviolet and solar lights,humidity,high temperature,oxidization by NO_4I,and biodegradation by cellulosomes.In this work,energy dispersive X-ray fluorescence was used to quantify S,Cl,K,Ca,Mn,Fe,Cu,Zn,As,Sr,Ba and Pb and X-ray diffraction spectrometry was used to compare the phase differences in the original paper samples and after each aging treatment.Different elemental compositions were observed in modern papers and in papyrus which allows distinguishing them.With a ternary diagram based on elemental composition,we can perfectly identify each kind of paper sample.The obtained results concerning the used artificial aging processes in paper show that only the oxidization by NO_4I and biodegradation by cellulosomes affected the elemental content of paper,for S,Cl,K,Ca and Sr.These results are evidenced in the dendograms performed with the elemental concentrations for treated and untreated samples,respectively.Some differences were obtained in the diffractograms for aging process of some papers,which means that crystal phase changes occurred during the corresponding aging process.