Physicochemical studies of cellulose acetate decomposition reactions

Abstract

SynopsisThis work is a continuation in these laboratories of the study of the source of undesirable optical properties of molded cellulose acetate. The origin, mechanism of formation, and structure of the colored compounds formed upon heating cellulose acetate in the presence of plasticizer were studied. Extraction of heated mixtures gave evidence indicating the colored compounds are intermediates containing a conjugated carbonyl group. Efforts to fractionate and isolate color-causing fractions were defeated by the well-known solvent inclusion difficulties and upset of the little-understood salt balance in the sample. The effects of additives known to degrade cellulose acetate were determined by heating mixtures of these materials with cellulose acetate dissolved in excess plasticizer. Acidic compounds caused the expected severe degradation and color formation. Air oxidation and free radical initiators had very little effect compared to the acidic materials. Inhibitors of the action of acidic conipounds (neutralizers) and of oxidative degradation were studied.