This report is the result of a three-year research program. It describes the chemical character of cellulose ethers as a general class of polymers and establishes an approximate ranking of the relative stability of each generic chemical subclass. Ranking the thermal stability of the polymers with respect to color change and loss in degree of polymerization led to the conclusion that as generic chemical classes, methylcellulose and carboxymethylcellulose appear to be the most stable of the cellulose ethers. Water-soluble ethylhydroxyethylcellulose apparently also possesses good stability. Of questionable long-term stability are hydroxyethylcellulose and hydroxy- propylcellulose. Ethylcellulose and organic-soluble ethylhydroxyethylcellulose proved to be of poor stability, potentially undergoing marked changes in twenty years or less under normal museum conditions. An important additional conclusion reached here, as well as in an earlier investigation, is that considerable variations in stability can occur within a generic chemical class from differences in the basic raw material, a natural product from plants, which is not a uniform, manufactured, chemical substance. Further variations can exist due to different manufacturing processes or commercial sources. Hence, commercial products must be evaluated individually to determine the most stable of a given generic type. Nonetheless, the authors believe the conclusions expressed here to be valid with regard to the relative stability of the generic chemical classes of cellulose ethers.

This report attempts to isolate and separately examine each of the factors known to lead to cellulose nitrate decomposition, and then relate their contribution to the instability of the polymer when it is used as a bonding agent for ceramics and as a lacquer for metal objects. These factors include deterioration caused by heat, radiation, or acid impurities, or through the loss of plasticizer. There is, moreover, decomposition caused autocatalytically by the initial breakdown products. In particular, the publication examines new information on chemical changes under ambient conditions that has been developed recently through advances in analytical procedures such as chemiluminescence, X-ray scanning spectroscopy (ESCA), and more sophisticated viscometry. This new information will be added to the large body of data, collected over the past 150 years, on the instability of cellulose nitrate under more severe conditions.

This series presents current research being conducted under the auspices of the Getty Conservation Institute.An overview of research from 1984 to 1994, including environmental controls in museums, the use of protective materials and analyses in the conservation of cultural objects and archaeological sites, and the use of new technologies for monitoring, documentation, and analysis.

This book addresses both classic concepts and state-of-the-art technologies surrounding cellulose science and technology. Integrating nanoscience and applications in materials, energy, biotechnology, and more, the book appeals broadly to students and researchers in chemistry, materials, energy, and environmental science. • Includes contributions from leading cellulose scientists worldwide, with five Anselm Payen Cellulose Award winners and two Hayashi Jisuke Cellulose Award winners • Deals with a highly applicable and timely topic, considering the current activities in the fields of bioeconomies, biorefineries, and biomass utilization • Maximizes readership by combining fundamental science and application development