PULSED MICROWAVE-INDUCED ACOUSTICS - AN INDIRECT METHOD FOR MONITORING DEPOLYMERIZATION OF PAPER VIA ONLINE MEASUREMENTS OF WATER SORPTION-DESORPTION KINETICS

The application of the microwave-induced acoustic technique, developed in this laboratory, as an indirect sensor of depolymerization of pape r via online measurements of water sorption and desorption kinetics in both lignin containing and lignin-free paper samples is described. Ex posure of paper samples to gaseous NO2 greatly accelerated the aging o f paper and is shown by this technique to have significant effects on the water sorption characteristics. Implications of these observations , related to damages effected by exposure to free radical environments and the resulting embrittlement and depolymerization of paper samples , is discussed.