Degradation of historic cellulose triacetate cinematographic film: The vinegar syndrome

Abstract

The degradation of cellulose triacetate based cinematographic film has been studied by moisture regain, viscometry, uv absorption, pH and degree of insolubilisation. Analysis of naturally aged films indicates a correlation between moisture regain, acidity and degree of degradation. Artificial ageing studies at various temperatures and at different humidities show that temperature, moisture regain and pH are important related factors in the degradation mechanism. The results show conclusively that the degradation of acetate based film, which is often accompanied by the release of acetic acid, is associated with an acid catalysed hydrolysis of the ester groups resulting in a consequent reduction in the molecular weight of the polymer. © 1987.