THE EFFECTS OF SEVERAL PAPER CHARACTERISTICS AND APPLICATION METHODS ON THE SUBLIMATION RATE OF CYCLODODECANE by Kelli A. Piotrowski A thesis submitted to the Department of Art In conformity with the requirements for the degree of Master of Art Conservation Queen’s University Kingston, Ontario, Canada (September, 2013) Copyright © Kelli Piotrowski, 2013 ABSTRACT Cyclododecane (CDD) is a waxy, solid cyclic hydrocarbon (C12H24) that sublimes at room temperature and possesses strong hydrophobicity. In paper conservation CDD is used principally as a temporary fixative of water-soluble media during aqueous treatments. Hydrophobicity, ease of reversibility, low toxicity, and absence of residues are reasons often cited for its use over alternative materials although the latter two claims continue to be debated in the literature. The sublimation rate has important implications for treatment planning as well as health and safety considerations given the dearth of reliable information on its toxicity and exposure limits. This study examined how the rate of sublimation is affected by fiber type, sizing, and surface finish as well as delivery in the molten phase and as a saturated solution in low boiling petroleum ether. The effect of warming the paper prior to application was also evaluated. Sublimation was monitored using gravimetric analysis after which samples were tested for residues with gas chromatography-flame ionization detection (GC-FID) to confirm complete sublimation. Water absorbency tests were conducted to determine whether this property is fully reestablished. Results suggested that the sublimation rate of CDD is affected minimally by all of the paper characteristics and application methods examined in this study. The main factors influencing the rate appear to be the thickness and mass of the CDD over a given surface area as well as temperature and ventilation. The GC-FID results showed that most of the CDD sublimed within several days of its disappearance from the paper surface regardless of the application method. Minimal changes occurred in the water absorbency of the samples following complete sublimation. ii ACKNOWLEDGEMENTS I would like to express my tremendous gratitude to my advisers Dr. Alison Murray and John O’Neill for their advice, guidance, and encouragement throughout my research. I would also like to thank Rosaleen Hill for her suggestions at various stages of my work. I am grateful to Dr. George Bevan of the Department of Classics, Dr. P. James McLelland of the Department of Chemical Engineering, and Dr. Bubby Kettlewell of the Analytical Services Unit for sharing their insights on statistical modeling and analysis. I am also indebted to Dr. Season Tse of the Canadian Conservation Institute for her generous comments and suggestions. I would like to extend my thanks to Dr. Allison Rutter and Paula Whitley of the Analytical Services Unit at Queen’s University and Dr. H. F. (Gus) Shurvell of the Art Conservation Program for their assistance in the technical analyses. Finally, I would like to thank my friends, family, and colleagues for their encouragement and support. iii TABLE OF CONTENTS Title page..……………………………………………………….…………………………………i Abstract...………..…………………………………………………………………………………ii Acknowledgements.……………..…………………………………………………………………iii Table of Contents..………………………………………………………………………………...iv List of Tables..……..………………………………………………………………………………vi List of Figures..……………………………………………………………………………………vii Chapter 1 Introduction......……………………………………………………………....………….1 Chapter 2 Literature Review………………………………………………………………………..3 2.1 Uses in Paper Conservation…………………………………………………………….3 2.2 Physical Properties……………………………………………………………………...8 2.3 Uses in Industry…………………………………………………………………….....10 2.4 Health and Safety……………………………………………………………………...11 2.5 Methods of Application……………………………………………………………….12 2.6 Factors that Affect Sublimation……………………………………………………….15 2.7 The Potential Presence of Residues……………………………………………....……18 Chapter 3 Experimental……………………………………………………………….…………..20 3.1 Evaluation of Cyclododecane Purity……………………………………….…………..21 3.2 Gravimetric Procedures to Determine CDD Sublimation Rates……………………….28 Experiment 1: Fiber Type…………………………………………................……..28 Experiment 2: Sized and Waterleaf Papers…………………………………...……31 Experiment 3: Finishes……………………………………………………………32 Experiment 4: Warmed and Unwarmed Substrates………………………………..33 Experiment 5: Molten CDD and CDD-Saturated Solution………………………..35 iv 3.3 GC-FID Procedures to Test for the Presence of Residues…………………………….38 3.4 Water Absorbency Tests………………………………………………………………39 Chapter 4 Results and Discussion…………………………………………………………………44 4.1 Gravimetric Analyses………………………………………………………………….44 4.2 Gas Chromatography-Flame Ionization Detection Analyses…………………………..58 4.3 Water-Absorbency Analyses…………………………………………………………...61 Chapter 5 Conclusions………………………………………………………….…………………68 Bibliography………………………………………………………………………………………71 Appendices Appendix 1: Materials and Suppliers………………………………………………………76 Appendix 2: Summary of Temperature and Relative Humidity during Gravimetric Tests…………………………………………………………………………77 Appendix 3: Dependence of Paper Mass on RH: Graphs of Controls…………………….78 Appendix 4: Calibration Curves and GC-FID Results for CDD Purity Characterization.…83 Appendix 5: GC-FID Results for Warmed and Unwarmed Whatman Filter Paper Samples Treated with Molten Cyclododecane…………………………………………..…84 Appendix 6: GC-FID Results for Waterleaf and Gelatin-Sized Flax Paper Samples Treated with Molten Cyclododecane…………………………………………..…86 Appendix 7: GC-FID Results for Artistico Rough Paper Samples Treated with Molten Cyclododecane and CDD-Saturated Solutions………………………………….…88 v LIST OF TABLES Table 1: Physical Properties of Cyclododecane………………………………………………..……9 Table 2: Average Initial Mass and Thickness of Cotton, Flax, Kozo, and Groundwood Fiber Paper Samples and Cyclododecane Applied as a Melt…………………….…..29 Table 3: Average Initial Mass and Thickness of Waterleaf and Gelatin-Sized Flax Paper Samples and Cyclododecane Applied as a Melt……………………………………………..32 Table 4: Average Initial Mass and Thickness of Cold Pressed, Hot Pressed, and Rough Paper Samples and Cyclododecane Applied as a Melt……………………………………...33 Table 5: Average Initial Mass and Thickness of Whatman Filter Paper Samples and Cyclododecane Applied as a Melt Onto Unwarmed and Warmed Substrates…………………...…34 Table 6: Average Initial Mass and Thickness of Whatman Filter Paper Samples and CDD Applied as a Melt and a Saturated Solution in Petroleum Ether (30°C-40°C)……….………37 Table 7: Average Percent Mass Loss of CDD from Cotton, Flax, Kozo, and Groundwood Papers Over Time………………………………………………………………….47 Table 8: Average Percent Mass Loss of CDD from Waterleaf and Gelatin-Sized Flax Papers Over Time……………………………………………………………………………50 Table 9: Average Percent Mass Loss of CDD Over Time from Cold Pressed, Hot Pressed, and Rough Finish Fabriano Artistico Papers………………………………………………………52 Table 10: Average Percent Mass Loss of CDD Over Time from Whatman Filter Paper Treated With Molten CDD to Unwarmed and Warmed Substrates……………………………….55 Table 11: Average Percent Mass Loss of CDD, Applied as a Melt and as a Saturated Solution in Petroleum Ether (30°C-40°C), from Fabriano Artistico Rough Finish Paper……….…57 Table 12: GC-FID Results of Select CDD-Treated Paper Samples Post-Sublimation……………..60 Table 13: Water Absorbency of Whatman Filter Paper Control and Warmed and Unwarmed Samples Post-Sublimation of Molten Cyclododecane……………………………………………...62 Table 14: Post-Sublimation Water Absorbency of Waterleaf and Gelatin-Sized Flax Paper Treated with Molten Cyclododecane………………………………………………………..64 Table 15: Post-Sublimation Water Absorbency of Fabriano Artistico Rough Finish Paper Treated with Molten CDD and CDD-Saturated Solution in Petroleum Ether (30ºC -40ºC) and Controls…………………………………………………………...……………………….…67 vi LIST OF FIGURES Figure 1: Molecular structures of cyclododecane…………………………………………………..10 Figure 2: Tools for applying cyclododecane……………………………………………...………..15 Figure 3: FTIR spectrum of cyclododecane………………………………………………….……23 Figure 4: Detail of GC-FID chromatogram of cyclododecane………………………………..…....25 Figure 5: GC-MS chromatogram of cyclododecane………………………………….………..…...27 Figure 6: Modified electric kistka…………………………………………………………….….....30 Figure 7: Arrangement of samples and controls in fume hood……………...……….………….…31 . Figure 8: Warming of paper samples……………………………………………………………....35 Figure 9: Detail of paper samples with templates and slide warmer……………..…………...….…35 Figure 10: Molten CDD applied to unwarmed Whatman filter paper #1…………….……....…….35 Figure 11: Molten CDD applied to warmed Whatman filter paper #1…………………………….35 Figure 12: Device for applying the CDD-saturated solution………………………………….…....38 Figure 13: Suspension of samples prepared with molten CDD and CDD-saturated solution..….…38 Figure 14: Preconditioning chamber……………………………………………………………....41 Figure 15: Mean sublimation rates of CDD, applied as a melt, from unsized cotton, flax, kozo, and groundwood papers plotted as a function of total mass loss against time………….46 Figure 16: Mean sublimation rates of CDD from cotton, flax, kozo, and groundwood papers plotted as a function of total mass against time with error bars showing standard deviations for 20 measurements…………………………………………………………………...47 Figure 17: Mean sublimation rates of CDD, applied as a melt, from waterleaf and gelatin-sized flax papers plotted as a function of total mass loss against time……………...………49 Figure 18: Mean sublimation rates of CDD