Cellulose Nitrate in Conservation

Charles Selwitz


80 pages

PDF file size: 540 KB MB


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.

Table of Contents

  • Chapter 1: The Use of Cellulose Nitrate in Art Conservation
  • Chapter 2: The Structural Chemistry of Commercial Cellulose Nitrate
  • Chapter 3: Causes of Instability
    • Hydrolytic Decomposition via Acid Catalyzed Ester Cleavage
    • Thermal Decomposition
    • Decomposition by Ultraviolet Radiation
    • Mechanisms of Primary Decomposition
    • Secondary Modes of Decomposition
  • Chapter 4: Cellulose Nitrate Stability at Ambient Conditions
    • Structural Factors for a More Stable Cellulose Nitrate
    • Avoidance of Acid Catalyzed Ester Cleavage
    • Thermal Cleavage
    • Ultraviolet Degradation
  • Chapter 5: The Use of Cellulose Nitrate as an Adhesive for Ceramics
  • Chapter 6: The Use of Cellulose Nitrate as a Metals Coating
    • Introduction
    • Compositions
    • Special Properties
    • Stability
  • Appendix: Proprietary Material Cited in the Text
  • References
  • Index

About the Authors

Charles M. Selwitz was with the Gulf Research and Development Company in Marmarville, Pennsylvania, until 1982 where he was Director of Synthetic Chemistry. Then he became an independent consultant, working primarily for the Getty Conservation Institute on problems of stone consolidation.