ACCELERATED DETERIORATION OF TEXTILES
Bi-monthly rept., no. 2, 1 Jun-31 Jul 1961
HARRIS RESEARCH LABS INC WASHINGTON DC
Pagination or Media Count:
Cellophane sheets were uniformly impregnated with ferric nitrate to ferric ion contents of 0.1 and 0.2. Single sheets were exposed to radiation from a carbon arc, filtered to exclude light below 2900 A, and consisting primarily of light b tween 3500 and 5000 A. Untreated cellophane was used as the control. Exposures up to 15 hours produced no measurable loss in tensile strength for the treated or untreated sheets. A 36 hour e posure caused about 35 strength loss in the sheets containing 0.2 ferric ion, but no measurable strength lo s i the untreated s ets or i tho e containing 0.1 ferric ion. Swatches of cotton fabric were similarly impregnated with ferric nitrate and exposed. Untreated fabric was used as the control. In contrast to cellophane, the ferric ion impregnated cotton was significantly degraded by exposure times as short as ten hours. 36 Hour exposure caused severe loss in the material containing 0.2 ferric ion, and some los even in the untreated control. Thus it appears that cellophane may be more resistant than cotton to catalyzed photooxidative degradation, even though both are essentially cellulose. Th current s udies are b ing extended to explain this behavior. An actinometer sys em based on uranyl ox late was set up and calibrat d.