An Indication of Molten Cellulose Produced in a Laser Beam

Abstract

A study has been made on the possibility of melting cellulose by a rapid heating and cooling technique, the basic idea being that the heating is carried out so rapidly that chemical reactions are minimized. In this study the rapid heating was carried out with'the heam from a continuous carbon dioxide laser. Immediately after heating, cooling took place in a stream of liquid nitrogen. The samples of condenser paper were analyzed by their ir spectra for a possible decrease in crystallinity. The ratio'of the absorption at 7.0 μm and 11.2 μm was taken as a measure of the degree of crystallinity. This crystallinity. index was 2.1 and 1.4 for untreated and irradiated condenser paper respectively. Model experiments at lower temperatures indicated that this decrease of crystallinity is not due to modification or degradation of the cellulose. Electron micrographs of these and other paper samples further substantiate that a melting of the cellulosic material has occurred.