1998-16

1998-16

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This Final Report on Phase 1 of the IUAM DEAE Analysis Project (CCI Service Request No CPMR 693) describes in detail the work performed by the Canadian Conservation Institute (CCI) for the Indiana University Art Museum (IUAM) on Phase 1 of IUAM Contract Proposal No 44877, Account No 43-200-27, for the IUAM project entitled “Investigation into the Effects and Removal of DEAE on Painting Media”, conducted under Grant No MT-0424-5-NC-013 from US Department of the Interior, National Parks Service. The IUAM DEAE Project is under the direction of Margaret Contompasis, Painting Conservator, IUAM. R. Scott Williams, Conservation Scientist (Chemist), Conservation Processes and Materials Research Section is the principle investigator for CCI.

Related Products: 1998-17 Analyzing the Effect of Diethylaminoethanol, an Indoor Air Pollutant, on Traditional Easel Paintings


The research objectives of the IUAM DEAE Project, as listed in Attachment A of the Contract, are:

  1. To determine if DEAE can penetrate the surface of the coated and uncoated paintings.
  2. To determine if, following penetration, DEAE reacts physically or chemically with the painting surface, and how those changes will affect subsequent cleaning.
  3. To determine if DEAE can be safely removed from the varnish or paint surface using conventional solvent systems.

The purpose of the CCI work, as described in Attachment A of the Contract, is to provide specific scientific analytical services, namely:

  1. To determine if DEAE is present on the surface, in accretion layers, in varnish layers, or in paint layers of paintings in the IUAM collections that have been exposed to humidified air containing DEAE.
  2. To determine whether painting surfaces and layers have been changed by DEAE.
  3. To determine whether DEAE can be removed safely from varnish or paint surfaces using conventional solvent treatments.

The CCI work is being carried out in two phases, with Phase 1 to establish appropriate analytical procedures for determining the presence and effects of DEAE on paintings, and Phase 2 to analyze the effects of DEAE and conservation treatments on DEAE contaminated paintings.

Phase 1 included the following tasks, as listed in Attachment A of the Contract.

  1. Examination of paintings in the IUAM collection that are apparently affected by DEAE contamination, and taking samples for analysis.
  2. Analysis of samples of surfaces, accretions, varnish and paint from DEAE contaminated paintings to determine most suitable techniques for detecting the presence of DEAE on paintings and characterizing the physical structure of the DEAE contaminated paintings
  3. Preparation of a report which summarizes the findings of Phase 1 investigations,

and recommends the analytical procedures that should be used for subsequent investigations. CCI has submitted two previous Progress Reports (September and October, 1996) summarizing development work and results. This Final Report incorporates, and supersedes, these previous Progress Reports Submission of this Report fulfils the obligations of CCI for Phase 1 of the IUAM DEAE Analysis Contract.

 

Final Report for Phase 1:
Analytical procedures for DEAE in DEAE contaminated paintings

 

 

 

Executive Summary

 

 

Results

  1. Traces of DEAE were detected by GC analysis of water swabs from 4” x 5” areas of the acrylic glazing on “Salon Rose Roix”. The amount detected was about 1.7 ng of DEAE per square millimeter of acrylic surface. This is about 18 times less than the amount detected on surfaces at Johnson Museum, Cornell University, when analyzed in 1983 (30 ng per square meter).
  2. DEAE was possibly detected by GC analysis at CCI of large cleaning swabs from “Swing Landscape” by Stuart Davis, and “Madame Chinnery”. The swabs analyzed were old ones taken more than a year prior to CCI involvement in the project and are ten to 100 times larger than swabs taken by Williams in 1996. They were not stored in air-tight containers and volatile components may have been lost. Barrett-Wilt (Chemistry, IU) detected DEAE in the swabs from “Swing Landscape” by GC analysis in 1994 and 1995.
  3. DEAE was possibly detected by GC analysis at CCI of 1.1 mg of dust from the back of “Peinture” by Soulages Barrett-Wilt detected DEAE by GC analysis.
  4. No DEAE was detected by GC analysis of water swabs from small, 3 mm x 3 mm, areas of painting surfaces from “Ste Catherine” or “Magdalen Reading”.
  5. No DEAE was detected by GC analysis of relatively large samples from “Blue Sky” (water swab from 16 mm x 13 mm area, or 0.5 mg scraping of varnish surface from 3 mm x 4 mm area) or “Green Trees” (water swab from 12 mm x 13 mm area, or 0.7 mg of scraping from paint surface from 4 mm x 5 mm area). These painting fragments had been exposed to steam humidified air containing DEAE in air conditioning vents at Lilly Library.
  6. No DEAE was detected by GC analysis of any dry swab from any object sampled.
  7. No free, unreacted DEAE was detected by FTIR analysis of samples from any painting However, “Blue Sky” and “Green Trees”, exposed at Lilly Library, and “Beach Scene” and “Portrait of Leila in Red” by Engel, showed some spectral characteristics that are similar to reaction products produced in the laboratory by direct addition of liquid DEAE to samples of varnishes and paints from various paintings. These reaction products have IR spectra that are different from material not treated with DEAE. The reaction products may be esters formed by reaction of carboxylic acids in the varnish and paint media with the alcohol group of DEAE (DEAE esters), or substituted ainmonium carboxylate salts formed by reaction of carboxylic acids with the nitrogen in the amine group of DEAE (DEAE carboxylates, analogous to reaction of ammonia with acids).
  8. IR spectroscopy indicates that “Ste Catherine” and “Magdalen Reading” contain water sensitive or water soluble materials like starch and protein DEAE or its reaction products were not detected on these paintings. In these paintings, hazing and other problems ascribed to contamination by DEAE might be due to the presence of these water soluble materials in or on the paints and varnishes.
  9. DEAE is a very good solvent for varnish resins and oil paints. When fragments of paintings were suspended in the vapor above a few drops of DEAE in a closed vial, the varnish absorbed so much DEAE vapor that the varnish dissolved and dripped off the fragment, and the paint became very soft.
  10. Liquid DEAE dissolves fresh dammar and aged danimar varnish film dating from 1948, and when this varnish/DEAE solution is cast on glass and allowed to sit in air, a hard film like a typical varnish film is formed.

Conclusions

  1. FTIR microspectroscopy is the best method to survey the paintings in the IUAM collection for the presence of DEAE and its reaction products. This method requires the smallest sample (particles much less than 1 mm in diameter) and provides the most information in a single analysis (medium and pigment composition, DEAE and reaction products, information from different layers, etc) The GC method provides only a yes or no answer for the presence of DEAE.
  2. Small amounts of DEAE esters and DEAE carboxylates, the reaction products of DEAE with varnish resins and oil paint media, but not free DEAE itself, were detected by FTIR microspectroscopy of particles measuring 50 μm (0.05 mm) in diameter. This is much smaller than the size of sample that is normally considered acceptable for sampling for chemical analysis.
  3. DEAE cannot be detected in dry swabs or water moistened swabs from areas less than about 30 mm x 30 mm by the GC technique used in this analysis The minimum area required to be swabbed in order to obtain a detectable amount of DEAE has not been determined conclusively, but areas measuring 4” x 5” (100 mm x 125 mm) on the acrylic glazing of “Salon Rose Roix” yielded a just barely detectable amount of DEAE so this would appear to be close to the area limit.
  4. DEAE and its reaction products are present in small concentrations on some surfaces, in some accretion layers, in some varnish layers, or in some paint layers, of some paintings in the IUAM collections The amounts present are very small and do not appear to be uniformly distributed since they are not detected in all paintings.
  5. No sample analyzed appears to have been significantly changed by the presence of DEAE reaction products, although these products may be responsible for some of the effects attributed to DEAE contamination.
  6. In some paintings, water soluble components in or on the varnishes and paints, rather than DEAE reaction products from DEAE contamination, may be the prime cause of abnormal behaviours observed when some paintings are swabbed with water moistened swabs.

Recommendations for further work

The results of these analyses indicate that DEAE and its reaction products are present on some paintings. Some of the effects attributed to DEAE contamination may be due to the presence of water soluble components like starch or protein (glue, egg, etc.). Since the number of paintings examined for this report is so small, a true picture of the extent of the DEAE problem cannot be drawn. More paintings should be analyzed.

FTIR microspectroscopy is the quickest, most informative, and least intrusive technique to use for this analysis.

To clarify the extent of the effects of DEAE and the mechanism of its interaction with paintings the following further work is recommended:

  1. Minuscule samples should be taken of varnishes and paints from many paintings that are apparently subject to DEAE contamination problems, for analysis by FTIR microspectroscopy, specifically for the presence DEAE esters and DEAE carboxylates, and for the presence of water soluble or water sensitive materials like starch and protein. This should quantify the number of paintings that are affected by DEAE and the extent of the DEAE problem.
  2. Test samples or model paintings should be exposed to DEAE vapors then analyzed by FTIR microspectroscopy to clarify the chemical reactions between painting media, DEAE, and DEAE reaction products. This has already been done to some extent in developing the FTIR microspectroscopic analysis procedure. The additional work needs to use more realistic exposure conditions such as exposure to a DEAE/air mixture of about 1% DEAE, rather than pure DEAE vapors or immersion in liquid DEAE This would determine whether the interactions under less severe exposure conditions are the same as at the higher concentrations used in the FTIR analysis.
  3. Test samples or model paintings should be analyzed by microscopical methods, before and after exposure to DEAE, and before and after cleaning treatments to determine the physical or structural effects of DEAE exposure and subsequent cleaning of DEAE exposed paintings.
  4. The analysis reported here has shown that for some paintings, wiping with water moistened swabs removes water soluble compounds from the painting, including starch and protein (“Ste Catherine”) and DEAE reaction products (“Green Trees”). Additional tests should be made to determine if swabbing with water moistened swabs is an effective treatment for removal of DEAE reaction products DEAE reaction products are polar compounds and therefore soluble in polar solvents like water and alcohols. They are also surface active agents and therefore may be soluble in nonpolar solvents like aliphatic and low aromatic hydrocarbons such as mineral spirits or naphtha. Alkanolamine soaps such as those produced by reaction of monoethanolarnine (MEA) with coconut or tall oil fatty acids show some solubility in these solvents. Analogous DEAE soaps with the increased hydrocarbon content due to substitution of the two hydrogens on the nitrogen of MEA by two ethyl groups will be even more soluble in these solvents. The effects of using these solvents to remove DEAE reaction products should be investigated. Using nonpolar solvents that may be less damaging to paintings than water, may be a valuable alternative procedure.

2. Examination of Paintings at IUAM

Scott Williams visited IUAM during the week of July 13-19, 1996. With Margaret Contompasis and Danae Thimme, paintings and other objects on display at the Art Museum and the Lilly Library of Indiana University were examined, in situ, with the naked eye. During this examination the phenomenon attributed to contamination by DEAE from the humidification system was observed. The phenomenon appeared primarily as a disruption of gloss in the form of a bluish film or haze on the surface of paintings, most noticeable over dark colored areas.

Additional paintings were examined more closely in the conservation laboratory by microscopical methods. A second phenomenon attributed to DEAE contamination was observed on these paintings. When some paintings are swabbed with water moistened swabs in areas showing the bluish film or haze, the film is removed, and the area develops a whitish hazed appearance. Continued swabbing with water moistened or saliva moistened swabs removes the hazed appearance from the area, and restores the healthy appearance to the varnish or paint film.

Samples were taken from these paintings by Scott Williams and Margaret Contompasis for chemical analysis at CCI.

3. Sample selection and collection

Samples consisted of wipings on small cotton swabs, powders and particles obtained by scraping the surface of the painting, or particles or flakes excised from the painting with a scalpel. Samples were taken from areas of paintings that showed effects attributed to the presence of DEAE such as hazy or greasy appearing surfaces, varnishes that became abnormally hazy or milky when swabbed with water, etc.

Cotton for swabs was prewashed with methanol. Swabs were prepared by wrapping a small wad of cotton batting around the tip of stainless steel forceps. Gloves were worn when wrapping the swabs to prevent transfer of fingerprints. The swabs measured about 2 mm diameter by 5 mm length. Wipings were done either with dry swabs or with deionized water moistened swabs. After wiping the surface the swabs were removed from the forceps and stored in glass vials closed with teflon/silicone septa with the teflon side facing inwards.

Scrapings were made by dragging a scalpel across a prescribed area of the painting surface in such a manner than only a single layer was removed, and usually only the upper surface of that layer. The operation was carried out while observing with a stereomicroscope. Scrapings were removed with the scalpel or a needle and transferred either to septum cappedglass vials or microscope slides. Samples on microscope slides were covered with another microscope slide then the two slides were taped together to trap the sample between them.

Particles or flakes were excised from the painting surfaces using a scalpel, then transferred and stored in septum capped glass vials.

Additional samples, taken by others more than a year prior to Williams’ visit, were supplied by Margaret Contamipasis. These samples consisted of water moistened swabs and powders brushed from the surfaces of paintings. They have not been stored in air-tight containers. Some of these samples were analyzed by gas chromatography at the Chemistry Department of Indiana University by Greg Barrett-Wilt (1996).

All samples are described in Appendix A.

4. Methods of Analysis

4.1. Thermal Desorption/Gas Chromatography/Mass Spectrometry (TD/GC/MS)

Several methods of analysis of DEAE and other tertiary amines by different analytical techniques have been published. Gas chromatographic methods use direct injection onto the GC column of underivatized DEAE in aqueous solutions (ASTM D 4983-89; Malaiyanda and Goddard, 1990), underivatized DEAE in organic solutions (Lester and White, 1967), and silylated derivatives of DEAE in organic solution (White and Swafford, 1973); desorption from absorbent gas sampling traps (Fannick, et al, 1983; Visscher, 1990); or direct injection of gas samples into special GC apparatus (Edgerton, et al., 1989). Liquid chromatographic methods rely on formation of colored or radioactive derivatives (Michelot, et al., 1983), as do spectrophotometric and colorimetric methods (Larrick, 1963; Miller, et al., 1967). Only the publications of Fannick, et al (1983) and Visscher (1990) DEAE with the analysis of DEAE in museums, and both use gas adsorbent trap – GC methods. The GC methods are most sensitive and convenient. For this project a thermal desorption (TD) method of sample introduction onto a GC column was chosen. This TD method is a modification of one that has been used for several years at CCI for GC/MS analysis of volatile compounds emitted by paints and adhesives.

The TD method involves two steps which are carried out in a Thermal Desorption Unit (TDU). In the first step, the sample preparation or loading mode, a sample of either gas or liquid is injected through a septum into a sample tube, an empty 1/4” OD glass tube, contained in a temperature controlled tube chamber, then the tube chamber sample preparation heating program is activated. Carrier gas flowing through the sample tube, sweeps the volatilized sample out of the sample tube onto an adsorbent tube which is a 1/4” OD, 1 mm ID glass tube packed with adsorbents (Carbotrap 301) that adsorb efficiently organic molecules having a size greater than equivalent to alkanes with about 2 to 3 carbon atoms (i.e., compounds with molecular weights greater than about 30-45 atomic mass units, amu). Thus, water, oxygen, carbon dioxide, and methanol, for example, pass through the adsorbent tube without being adsorbed, whereas larger molecules such as DEAE (MW =117 amu) are completely adsorbed in the adsorbent tube. By this means, small amounts of DEAE can be concentrated in the adsorbent tube by injecting large volumes of methanol solution (e.g., 5 μL) into the sample tube.

In the second step, the desorption mode, the adsorbent tube with the adsorbed analyte is placed in the tube chamber. Carrier gas flow through the tube is switched from the path to the adsorbent tube to the path through the GC column. The temperature of the tube chamber is raised rapidly to 330 C to desorb the sample from the adsorbent tube and the desorbed sample is swept through the GC where separation and subsequent detection with the mass spectrometer occurs.

One advantage of this TD sample injection method is that concentration of the DEAE in methanol extracts by evaporation of the methanol is not necessary, so there is no loss of DEAE by simultaneous evaporation, or azeotropic distillation. Another advantage is that, since most of the methanol passes through the adsorbent tube, no methanol is injected onto the analytical column when the sample is desorbed so there is no large background signal in the chromatogram due to methanol solvent. Contaminants in the methanol are concentrated so high purity solvent is required.

All swabs were extracted with methanol added directly to the sample vial, typically 0.5 mL which was just sufficient to cover the swabs in the vials For gas chromatographic analysis, samples of the extract were removed from the vial by a syringe pierced through the septum in the vial cap then injected into the thermal desorption unit.

Powder and flake samples stored in vials were extracted, dissolved, or dispersed in methanol, typically 0.25 to 0.5 mL, by addition of methanol directly to the vial. Samples of these liquids were removed from the vial by a syringe pierced through the septum in the vial cap.

To prevent loss of volatile DEAE or its reaction products, all samples collected during Williams’ visit were kept in septum sealed glass vials, except for the brief period when methanol was added to the vial Also no methanol solutions or mixtures were subjected to evaporation to concentrate the samples.

The TD/GC/MS apparatus and instrument settings were as follows:

Gas Chromatograph/Mass Spectrometer Hewlett Packard (HP) 5870 GC with a HP 5970B Mass Selective Detector (manual dated January 1986) controlled by a HP 59970C MS ChemStation with HIP 59974J GC/MS Software (revision 3.1.1, copyright 1986) using a HP 9133H Disc Drive.

GC Column: DB-WAX, 30 m x 0.25 mm ID x 0.25 μm film thickness (J&W Scientific, P/N 122-7032) received on 16/8/94.

GC Oven: 45°C for 2 min, then to 200°C at 20oC/min and hold.

Thermal Desorption Unit: Dynathenn Analytical Instruments, inc. Thermal Desorption Unit (TDU) Model 890/891 from Supelco, Inc.

TDU Adsorbent Trap: Carbotrap 301 Multibed Thermal Desorption Tube, 1 mm ID (Supelco Catalog No. 2-0354).

Split Ratio at TDU exit. 60:40 (column:vent)

TDU Temperature Conditions:
Preparation (loading) mode: initial approx 45°C, final 300°C, 4 min hold.
Desorption mode: initial: approx 45°C, final: 330°’C, 4 min hold.

Injection Volume (typical): 5 μL of methanol extract or solution using a Hamilton 701 syringe.

4.2. Fourier Transform Infrared (FTIR) Spectroscopy

A few individual particles from powdery scrapings or excised chips and flakes were analyzed by Fourier transform infrared spectroscopy using a Spectra-Tech IR-Plan lit microscope
interfaced to a Bomem MB-120 FTIR Spectrometer.

Samples were prepared in a low pressure diamond anvil sample cell from High Pressure Diamond Optics by placing a particle on one anvil, assembling the cell, then squeezing the sample by applying pressure until the sample was about 10 μm thick. The diamond cell was opened and the anvil with the sample stuck to it was mounted in the IR microscope for spectroscopy of circular areas of the squeezed samples measuring 100 μm in diameter, using clear areas of the diamond anvil immediately adjacent to the sample for background spectra for each sample spectrum.

The typical sample size was about 10 μm thick by 100 μm in diameter. Assuming that the density of the sample is about 1 gm/cm2, the weight of the sample analyzed can be calculated:

10 μm x π x (50 μm)2=l0x 3.14 x 50 x 50 = 78450 μm3
=7.8E4 μm3 x (1 cm/ 104 μm)3
=7.8E-8 cm3
=7.8E-8 cm3 x 1 gm(sample)/cm3
=7.8E-8 gm(sample)
=78 ng(sample)

FTIR spectroscopy is usually capable of detecting components in mixtures that comprise 1% or more of the total sample weight when there is no overlap of absorption bands for the components. DEAE has absorption bands that are not masked by absorption bands of resin and acrylic varnishes or oil and protein paint media. Thus the limit of detection for DEAE in painting samples by this FTIR microspectroscopic technique should be about 1% of 78 ng or 0.78 ng DEAE.

When the sample is on the diamond anvils it can be treated with reagents by placing drops of reagents on the sample as it rests on the diamond, allowing these to react and then evaporate, then acquiring spectra of the dry reaction products.

This procedure has been used for years at CCI to remove lead and calcium carbonates from samples by adding hydrochloric acid (which reacts with the carbonate to produce carbon dioxide gas and IR transparent calcium or lead chlorides) or to remove silica and silicates by adding hydrofluoric acid (which produces volatile silicon tetrafluoride and IR transparent metal fluorides).

The judicious addition of hydrochloric acid or sodium or ammonium hydroxide in various sequences can also be used to probe carboxylic ester, acid, and salt functional groups. For example, the presence of a carboxylate salt (e.g., zinc stearate) can be confirmed by observing the shift of the Zn carboxylate absorption from 1540 cm-1 to 1710 cm-1 for carboxylic acid when hydrochloric acid is added. Subsequent addition of sodium hydroxide causes the 1710 cm-1 peak of acid to disappear while the 1580-1540 cm-1 peak for sodium carboxylate salt (soap), appears.

The effects of DEAE on the IR spectra of samples was investigated by placing a drop of DEAE on the sample after an initial spectrum of the untreated material had been obtained. These reactions were observed using a stereomicroscope. The process of evaporation of the DEAE was observed and in some cases hastened by the heat from the illuminating lamps Reaction products with the DEAE were subsequently treated with water, mineral acids, and alkalis to observe their reactions. Spectra of the reaction products were acquired.

4.3. Freeze fracture experiments and scanning electron microscopy (SEM)

5 mm wide strips were cut from the test paintings using a sharp scalpel yielding test pieces about 5 mm wide x 50 mm long. The test pieces were immersed in liquid nitrogen (LN2). Immediately after removal from the LN2 the test pieces were bent around a 5 mm diameter metal rod to fracture the paint layer. The support layer did not fracture and was cut with a scalpel. Two pieces of each test piece resulted. One piece has been stored in a glass vial as a control. The other piece has been suspended by a thread in a vial over 1 mL of pure DEAE. These were to be examined by scanning electron microscopy (SEM).

5. Results of Analysis

The results of all TD/GC/MS analyses are presented in Appendix B. The results for FTIR spectroscopic analysis are presented in Appendix C. These results are discussed here in detail for each of the objects sampled.

5.1. Analysis of DEAE reference samples and boiler treatment products

The mass spectrum and IR spectrum of DEAE reference material, Aldrich Catalog No 24004-4 (N,N-Diethylethanolamine, 99+ %), agree with published spectra.

The mass spectra and lit spectra of boiler treatment products are identical to the reference material. Only DEAE was detected by GC analysis.

5.1.1. Lower limit of detection by TD/GC/MSD of DEAE dissolved in methanol

To determine the sensitivity of the TD/GC/MS method, solutions of Aldrich DEAE in methanol were analyzed. The results are listed in Appendix B. Using injection volumes of 5 μL of solution, DEAE in methanol at 50 ppm (v/v) has been detected with an 86 amu (atomic mass unit) ion peak height of about 20000. DEAE has a density of 0 88 g/mL, therefore,

50 ppm (v/v)
= 50 x 10-6 mL(deae)/mL(soln)
= 50 x 10-6 mL(deae)/mL(soln) x 0.88 g(deae)/mL(deae)
= 44 x 10-6 g(deae)/mL(soln)
= 44 μg(deae)mL(soln)
= 44 μg(deae)/mL(soln) x 10-3 mL/μL
= 44 x 10-3 μg(deae)/μL(soln)
= 44 ng(deae)/μL(soln).

5 μL of 50 ppm DEAE in methanol produced a distinct total ion chromatogram (TIC) peak in the gas chromatogram and a mass spectrum of DEAE at the retention time of the peak maximum for this peak. The same volumes of 10 and 16 ppm DEAE in methanol produced small TIC peaks with peak height only 2 or 3 times the background noise and mass spectra missing ions at 117 amu and sometimes at 102 amu which are normally found in mass spectra of DEAE. Thus the lowest limit of detection under these conditions is about 5 μL of 50 ppm DEAE in methanol or 5 μL(soln) x 44 ng(deae)/μL(soln) = 220 ng(deae), based on the 86 amu ion peak height when the ions at 102 amu and 117 amu are also present.

5.1.2. Comparison of GC analysis of headspace gases versus liquid extracts

An initial effort was made to analyze the headspace gas above samples stored in sealed vials, to determine if any DEAE had been emitted by the samples. DEAE was not detected in 1 mL samples of headspace in any swabs, scrapings or flakes from painting or other surfaces
and this procedure was abandoned. Either the procedure is not sufficiently sensitive to detect the low concentration of DEAE that may be present (i.e., less than 220 ng of DEAE per mL of air in the vial), or the DEAE is contained in the samples in an involatile form that does not evaporate into the headspace in sufficient concentration to be detected.

5.2. Samples taken by Williams

Swabs from the surface of the acrylic glazing on the poster “Salon Rose Roix” hanging on the IUAM painting storage rack

The results for this object are discussed first, since these samples are from the largest area of any object sampled and are most likely to have DEAE, if the exposure of the “Salon Rose Roix” in storage was the same as the other objects on display.

The acrylic sheet was covered with a dusty and greasy appearing film. Single dry and water moistened swabs were wiped across the acrylic sheet over four different areas measuring about 4” x 5” each. In Area 1, dry swabs were used first, followed by water moistened swabs. In Areas 2, 3 and 4, a water moistened swab was used first, followed by dry swabs to wipe up water droplets.

These swabs were extracted with 0.5 mL methanol. 5 μL of the extract was analyzed by TD/GC/MS.

Only water moistened swabs removed detectable amounts of DEAE, but only a just barely detectable amount. Wiping areas as large as 4” x 5” with dry swabs does not remove detectable amounts of DEAE even though this wiping appears to move material around on the surface.

Comparison of the 86 amu ion peak heights for the water moistened swab extracts with those of the DEAE/methanol solutions shows that the concentration of the DEAE in the swab extract is about 50 ppm = 44 ng(deae)/μL(soln). From the total volume of the extract (0.5 mL = 500 μL) and the area of the acrylic wiped (4” x 5” =20 in2) the amount of DEAE per unit area of

surface of acrylic can be calculated:
44 ng(deae)/μL(soln) x 500 μ(soln)
= 22000 ng(deae)
= 22000 ng(deae) / [20 in2 x (25 4 mm/in)2]
= 1.7 ng(deae)/mm2(acrylic)

The amount of DEAE per unit area of surface of the acrylic is 1.7 ng/mm2.

FTIR spectroscopy of the deposits on the swabs, or of material removed from the acrylic glazing, was not performed.

Swabs and scrapings from the surface of “Ste. Catherine” by Francesco Zagnelli (IUAM 77.43)

Small areas of the painting which showed a hazy, milky, or greasy appearing surface deposit were swabbed over areas about 3 mm x 3 mm, using small dry or water moistened swabs. Scrapings of the varnish and tiny flakes of paint were taken from these areas, before and after swabbing. All swabs were extracted with 0.5 mL of methanol then analyzed by GC, and the solids were analyzed by FTIR.

No DEAE was detected in any of the swabs or powdery scrapings by GC. The total area wiped was 9 mm2. If the painting has the same amount of DEAE per unit area as the acrylic sheet then we expect a total of 9 mm2 x 1.7 ng/mm2 = 15.3 ng(deae) to be in the 0.5 mL of methanol extract. This is 15.3 ng(deae) / 500 μL(soln) = 0.0306 ng(deae)/μL(soln) which is about 1000 times less than the minimum detectable concentration of DEAE by this TD/GC/MS technique. If there is DEAE in the paint layer, not just on the varnish layer, then the amount of DEAE available for removal by the swabbing might be higher.

Several particles of varnish scraped from the surface (samples 3, 3-1, 10, and 11) and paint from under the varnish (sample 13) were analyzed by IR spectroscopy. IR spectra of the varnishes are very similar to aged dammar and show mainly absorptions for carboxylic acids (1700 cm-1) but not esters (1735 cm-1).

Varnish taken before the surface had been wiped with water moistened swabs (Samples 3 and 3-1), have additional absorptions which may be attributed to starch or other similar carbohydrate (absorptions at 1030 cm-1 from C-O-C bonds). Samples 10 and 11, varnish taken after the surface had been wiped with water moistened swabs, do not have carbohydrate. It is possible that carbohydrate was initially present as in sample 3, but that this water soluble component was removed by wiping with water moistened swabs.

Addition of DEAE to the varnish causes the varnish to disperse completely, with most of it dissolving, leaving only a trace of undissolved gelatinous material. DEAE converted the varnish acids (1710 cm-1 to esters (1735 cm-1), presumably by a reaction between the alcohol group of the DEAE and the acid groups of the varnish resin. The 1030 cm-1 band, attributed to carbohydrate is not affected. The gelatinous material which is not dissolved by DEAE may be the carbohydrate, the source of the 1030 cm-1 band. The 1030 cm-1 band did appear to be more abundant in sample 3 which had the gelatinous material than in samples 10 and 11 which did not, supporting this hypothesis.

There is no indication in the IR spectra that DEAE is present in the varnish. The presence of the carbohydrate may be responsible for the haziness observed when the painting is treated with water. Water may swell and dissolve the carbohydrate from the varnish, disrupting the layer sufficiently to cause optical changes. The disappearance of the haziness when the hazy area is swabbed with saliva, but not with water, may be due to the replenishment of the lost carbohydrate by the involatile components of the saliva (enzymes and other proteins, mucins (glycoproteins), and carbohydrates, etc.), which are not present in water which is consequently ineffective in reducing the hazing.

Sample 13, a flake of varnish and paint taken before swabbing with water, contains carboxylic acids (1707 cm-1) but no ester (1735 cm-1), plus protein (1652/1535 cm-1) which may be glue or egg, carbonate (lead or calcium, not determined) and barium sulfate. The carbonates were removed by reaction with hydrochloric acid as described above. This treatment also removed the protein peaks. The carbonate free sample was reacted with DEAE This converted the acid (1707 cm-1) to ester (1735 cm-1) and regenerated the protein peaks (1655/1567 cm-1). Further treatment of this with hydrochloric acid converted some of the ester to acid and once again removed the protein peak. The barium sulfate was unaffected by all reagents.

The was no evidence in the IR spectra that DEAE was present in the paint, unless the 1650/1560 cm-1 peaks which were attributed to protein were actually DEAE reaction products. This latter is unlikely since several separate experiments where resins, fatty acids, and esters were reacted with DEAE did not produce the 1650/1560 cm-1 pair. These are much more likely due to protein.

The presence of a water sensitive or soluble material, the protein, may be responsible for the hazing behaviour when the painting is treated with water moistened swabs, in the same manner as described for Sample 3.

Swabs and scrapings from “Magdalen Reading” by Master of the Female Half-Lengths (IUAM 77.12.1)

GC analysis of methanol extracts of dry and water moistened swabs, and solid scrapings of varnish and paint, did not detect any DEAE.

IR spectroscopic analysis of the varnish on “Magdalen Reading” showed that it is composed predominantly of resin acids, typical of resin varnishes like dammar. As in the case of “Ste. Catherine” there appears to be an admixture of a small amount of carbohydrate like starch. The spectrum of varnish from a water swabbed area is almost indistinguishable from that of a varnish that has not been treated. There is little or no reduction in the carbohydrate after water swabbing, contrary to what was observed for “Ste Catherine”.

The IR spectrum of paint taken from an area after the varnish had been scraped away has the typical pattern (fingerprint) of ortho-phthalate alkyd, i.e., alkyd paint. It is definitely not a typical vegetable drying oil. There are several other weak but sharp peaks in the spectra that are reminiscent of the patterns obtained from red organic pigments. Their increased intensity in portions of the sample that are deeper red in color supports the attribution of these peaks to red organic pigments.

The area where this sample was taken should be examined to see if it is an overpainted area. Otherwise IUAM may have the earliest example of use of alkyd paint.

Solid scrapings from “Beach Scene” by Harry Engel

The spectra of waxy orange paint and the waxy brown paint are nearly identical to that of zinc stearate. All the peaks present in zinc stearate spectrum are present in the sample spectra. The slight differences in the spectra of the two colors may be attributed to absorptions from different pigments.

Addition of DEAE to these paints caused them to dissolve or disperse. The DEAE evaporates away to leave a dry reaction product. The carboxylate peak of the zinc stearate (1540 cm-1) is considerably reduced and a new peak at 1592 cm-1 appears. The ester (1735 cm-1) appears to be unaffected. Since the 1592 cm-1 peak was not initially present in the medium before treatment with DEAE, it is most likely that it is from a reaction product of DEAE with the carboxylate. The formation of esters by reaction of DEAE with paint and varnish media has been described above. However. carboxylic esters usually absorb around 1735 cm-1 whereas carboxylate salts absorb in the range 1500-1600 cm-1.Thus the band at 1592 cm-1 is more likely from a carboxylate salt than an ester.

In the presence of sufficient water, DEAE is most likely present in a protonated form, analogous to the aminonium ion from ammonia in water. This protonated DEAE may react with carboxylic acids to produce a DEAE carboxylate salt, in the same way the ammonium ion reacts with carboxylic acids to form ammonium carboxylate salts Ammonium carboxylates have carbonyl absorptions in the range 1600-1550 cm-1 (citrate and oxalate: 1600 cm-1, tartrate- 1576 cm-1, acetate- 1568 cm-1). Apparently some zinc carboxylate (1540 cm-1) has been converted into a protonated DEAE carboxylate salt (1592 cm-1. When the DEAE reaction product is treated with hydrochloric acid, the ester (1735 cm-1) the DEAE carboxylate salt (1592 curl, and the unreacted zinc carboxylate (1540 cm-1 are converted to carboxylic acid (1710 cm-1). These ester/acid/salt conversions at different acidities are typical reactions for these functional groups and have been observed often in analyses where oil paint samples have been reacted with mineral acids and alkalis, in this manner.

A medium that is so rich in zinc carboxylate soap is a very unusual paint medium. Zinc carboxylate has been used in oil paints supplied in tubes to help prevent the pigment from settling and caking (Mayer, 1981) but it is not used at such high concentrations for this purpose. Such high concentration of carboxylate soap would tend to give a very weak film that would be easily smeared or wiped off. This would behave very differently from a normal oil or acrylic paint, and this different behaviour may be erroneously attributed to effects of DEAE contamination.

Solid scrapings from “Portrait of Leila in Red” by Harry Engel (IUAM 71.86.8)

The varnish on this painting is a clear, colorless, elastic film. It cannot be scraped, but can be peeled off the underlying paint. The spectrum of a fragment that was peeled off very closely matched the spectrum of poly(butyl methacrylate), a commonly used acrylic varnish obtainable from many sources (Williams, 1994).

When DEAE was added to this varnish, the varnish varnish completely dissolved then redeposited as a film within minutes as the DEAE evaporated. The spectrum of the redeposited film was identical to the untreated material. Although there is dissolution, there is no apparent permanent chemical reaction between the poly(buty] methacrylate) varnish and DEAE.
There is no evidence in the IR analysis for the presence of DEAE or any reaction product of DEAE with the poly(butyl methacrylate) varnish.

IR spectroscopy of the brown paint shows it is predominantly a mixture of carboxylic acid and ester, perhaps a mixture of oil and varnish resin. It also contains a significant proportion of protein (1636/1537 cm-1), perhaps egg or glue, perhaps as much as 25%. The presence of the protein may give this paint abnormally high sensitivity to water. Barium sulfate is also present, but not calcium or lead carbonate.

This paint dissolved or dispersed a bit in DEAE, but not as much as did resin and acrylic varnishes, or the zinc carboxylate paints.

Addition of DEAE to this paint results in a decrease in the intensity of the ester/acid peak (1735/1710 cm-1) and the appearance of a strong peak at 1592 cm-1.Peaks at 1460, 1402, 1320 cm-1 become more prominent. This is the same reaction as for Sample 16 of “Beach Scene” but occured to a much greater extent in “Leila”. When hydrochloric acid is added to the DEAE reaction product the 1592 cm-1 peak disappears and an acid peak at 1709 cm-1 reappears, as in “Beach Scene”.

The behaviour of the “protein” at 1632/1537 cm-1 is different to what was expected DEAE caused the 1537 cm-1 peak to disappear but not 1632 cm-1. Normally these two peaks behave as a pair, both increasing or decreasing in unison. Their separate behaviour suggests that these peaks might not indicate protein.

Swabs from acrylic strip dated 11/9/87

This sample is an acrylic strip that was put “on display”, suspended by a wire, in the gallery on 11/9/87. It currently has a hazy coating on both sides. Methanol moistened swabs were wiped across areas measuring 35 mm x 35 mm. No DEAE was detected by GC analysis of methanol extracts of these swabs. The deposit was not analyzed by IR spectroscopy.

Solid scrapings from fragments of paintings exposed in air conditioning diffuser vent at Lilly Library

“Blue Sky”
An area measuring 3 mm x 4 mm, and weighing 0.5 mg was scraped from the surface of the painting, then dissolved in 0.5 mL of methanol. An area measuring 16 mm x 13 mm was wiped with two consecutive water moistened swabs and these were extracted together with methanol. GC analysis of these solutions did not detect DEAE in either scraping or swab.

There is no varnish on “Blue Sky”. IR spectra of blue paint show ester, typical of drying oil (but not like an acrylic), barium sulfate, and a small amount of carbonate (calcium or lead, not determined). There is also a strong peak at 1587 cm-1 which is typical of aluminum carboxylate salts, such as aluminum stearate or aluminum palmitate. These are used in paints in the same way as zinc stearate, as indicated in the discussion of result for “Beach Scene”. This may also be a protonated DEAE carboxylate, as discussed for “Beach Scene”.

Addition of DEAE does not cause significant dispersion of the sample and does not change the spectrum. This suggests that if DEAE reacts with the paint, it did so completely while the paint was exposed. When treated with hydrochloric acid, ester (1735 cm-1) and carboxylate (1587 cm-1 disappear while carboxylic acid (1712 cm-1) appears. Carbonate is also destroyed. Addition of DEAE to the hydrochloric acid reaction product regenerates the ester (1735 cm-1) and a very broad peak about 1600-1610 cm-1. This behavior with DEAE and HC1 is like that described for “Beach Scene” and “Portrait of Leila in Red”.

“Green Trees”
An area measuring 4 mm x 5 mm, and weighing 0.7 mg was scraped from the surface of the painting, then dissolved in 0.5 mL of methanol. An area measuring 12 mm x 13 mm was wiped with two consecutive water moistened swabs and these were extracted together with methanol. GC analysis of these solutions did not detect DEAE in either scrapings or swabs.

This painting has a thick yellow varnish. The lit spectrum of this varnish is very similar to “Damnmar March 1948”, a film of dammar varnish cast on glass in 1948, in the CCI collection. There is no glue present in the varnish. The spectrum has a broad strong band at 1716 cm-1 perhaps with a shoulder at around 1600 cm-1 which may be carboxylate salt like that previously discussed. This possible carboxylate peak is orders of magnitude less intense in this sample than in the oil paint for “Blue Sky, in accordance with the observation that the carboxylates are most prevalent in oil, not resin, media.

Addition of DEAE produces a reaction product with a new and very different spectrum. The acid (1707 cm-1) is reduced and a strong peak at 1572 cm-1 is produced. The appearance of the band at 1572 cm-1 suggests a protonated DEAE carboxylate salt has been formed analogous to that formed from zinc stearate. The slightly different frequency of the absorption (1572 cm-1 instead of 1592 cm-1) may be because resin acids (terpenic acids) are different from fatty acids which may cause slight frequency shifts for the salts. The reaction product after subsequent treatment with HC1 has a spectrum nearly identical to the original untreated (but exposed) varnish, as it should be for a protonated DEAE carboxylate.

The reaction of DEAE with the varnish sample suggests that the reaction of varnish with DEAE during the time of exposure in the Lilly Library had not gone to completion. This may be because the varnish is very thick and there simply is more of it to be reacted than in the case of the paint of “Blue Sky”, which appeared to have reacted to completion.

An area of the varnish was vigorously scrubbed with a water moistened swab, then a spectrum of the varnish was obtained. This spectrum was very nearly identical to varnish from an untreated spot, but the shoulder at about 1600 cm-1 which is in the untreated varnish is absent from the water swabbed varnish. The 1600 cm-1 peak is tentatively attributed to a protonated DEAE resin carboxylate soap. The behaviour towards water indicates its solubilty and the potential that it will be extracted by water moistened swabs, which may lead to hazing It is reasonable to expect the DEAE resin carboxylate to be water soluble.

5.3. Samples taken by others

More than a year before CCI involvement in the DEAE project, samples consisting of water moistened swabs and powders brushed from the surfaces of paintings bad been taken for analysis at the Chemistry Department of Indiana University (Barrett-Wilt, 1996). These swabs and powders were analyzed for this report. These samples have not been stored in air-tight containers.

Cleaning swabs from “Madame Chinnery”

Small amounts of DEAE was detected by GC analysis at CCI in methanol extracts of some, but not all, swabs from “Madame Chinnery”.

Cleaning swabs from Mylar on back of “Swing Landscape’ by Stuart Davis Powder from “Peinture” by Soulages (70.86)
Gas chromatograms obtained by CCI of methanol extracts of the swabs from “Swing Landscape” by Stuart Davis, and methanol solutions of the powder from “Peinture” by Soulages, had a weak peak at a retention time greater than that of reference DEAE, and also had a mass spectrum with some but not all of the characteristic ions for DEAE. A very small amount of DEAE may have been present. However, the poor match of retention time and mass spectrum with DEAE standards indicates that this is unlikely.

Barrett-Wilt (1996) detected DEAE by GC analysis in swabs from “Swing Landscape” (sample GBW0054, 30 Nov 96 and sample GBW0008: S.18 “Stuart Davis #2 surf dirt”, 7 Jun 95) and in powder from “Peinture” (GABW0009, 4 Apr 96).

Cleaning swabs from “Interior of Church” by E. DeWitte
Cleaning swabs from “Portrait of a Lady” by Terborch
Powder from “La Fenetre” by Balthus (70,62)

No DEAE was detected by GC analysis at CCI in the methanol extracts of the swabs from “Interior of Church” by DeWitte or “Portrait of a Lady” by Terborch, or in methanol extracts of powder from “La Fenetre” by Baithus.

Barrett-Wilt but did not detect DEAE in powder from “La Fenetre” (GABW0008, 4 Apr 96). Barrett-Wilt’s results for “Madame Chinnery”, “Interior of Church” and “Portrait of a Lady” were not available for comparison.

Powder from “Tie Ring”

This sample, consisting of powder sandwiched between two microscope slides, labelled “de Ring”, was analyzed by FTIR spectroscopy. Its spectrum matches a copolymer of vinyl acetate with a few percent of ethylene (less than 5% ethylene). It was not analyzed by GC.

5.4. Freeze fracture and DEAE incubation for SEM examination

Strips of “Horses” (Research Painting #3) and “Sea Scape” (Research Painting #5) were cooled in liquid nitrogen to make them brittle then fractured by bending over a metal rod. One piece of each fractured strip was suspended in a glass vial above a few drops of DEAE. When examined 23 days after being set up, it was observed that the varnish on “Horses” has absorbed so much DEAE that it had dissolved and the solution had dripped off the painting. The green and brown colors had also severely faded or in some other way degraded. The strip of “Sea Scape” had bent and in so doing come into contact with the side wall of the vial where it had stuck. The paint layer was wrinkled and soft. No SEM analysis was done.

6. Discussion of Results

The amount of DEAE per unit area of surface of the acrylic glazing on “Salon Rose Roix” was determined to be 1.7 ng per square meter. Fannick, et al (1983) reported that they found 30 mg of DEAE per square meter of exposed surface from their analysis of “bulk samples” of plastic film that had been exposed to the atmosphere of the Johnson Museum, Cornell University “for years”. 30 mg of DEAE per square meter is 30 mg/rn2 x 106 ng/mg 10-6 m2/mm2 = 30 ng(deae)/mm2 or an amount roughly 18 times greater than that observed on the glazing of “Salon Rose Roix”.

Very little free, unreacted DEAE was found on any surface. This is not surprising. DEAE is a volatile liquid. A drop on a microscope slide evaporates to dryness in about 1 minute. Only if it reacts with compounds in the painting will it be present, and then, only as a “fixed”, involatile reaction product.

There does appear to have been some reaction of DEAE with varnish and paint media.

There appear to be two mechanisms operating. In one, the alcohol group of the DEAE reacts with acid groups in the media to produce esters (DEAE esters). In the other, the nitrogen of the amine group in DEAE reacts with the acid groups in the media to produce substituted ammonium carboxylate salts (DEAE carboxylates).

There is a complex interaction between DEAE, acids, esters, and carboxylate salts in the medium, and acidic or basic reagents added to the medium during trealment. This interaction is not yet clear, but the following is probably true. The DEAE esters are not likely to be water soluble, whereas the DEAE carboxylate salts probably are. Any medium that has a significant concentration of DEAE carboxylate salt may be affected abnormally by water.

Although the small amounts of DEAE reaction products detected may be responsible for some of the subtle effects attributed to DEAE contamination, no sample analyzed has chemically reacted very much with DEAE, and in those samples where DEAE reaction products were found, only relatively small amounts of these were present.

Samples from some paintings contain water soluble or water sensitive components such as carbohydrates and proteins, which are unrelated to DEAE contamination. In these paintings, the effects attributed to DEAE contamination might be due to the presence of the water sensitive components.

No SEM examination was carried out during this work. Upon reflection, SEM examination did not seem to be an appropriate technique to determine damage caused by DEAE contamination. While it may be possible to characterize the current structure of surfaces or cross-sections of paintings, this will only give a snap-shot of the current state of the paintings. This will not permit any assessment of changes caused by exposure to DEAE because we have no data on the structure of the paintings before DEAE exposure for comparison. SEM or other microscopical analysis may be of some use in determining how treatments change the structure, but in the absence of data on how the painting would respond if it had not been exposed to DEAE, changes observed cannot be directly related to the effects of DEAE.

7. Conclusions

  1. FTIR microspectroscopy is the best method to survey the paintings in the IUAM collection for the presence of DEAE and its reaction products. This method requires the smallest sample (particles much less than I mm in diameter) and provides the most information in a single analysis (medium and pigment composition, DEAE and reaction products, information from different layers, etc). The GC method provides only a yes or no answer for the presence of DEAE.
  2. Small amounts of DEAE esters and DEAE carboxylates, the reaction products of DEAE with varnish resins and oil paint media, but not free DEAE itself, were detected by FTIR microspectroscopy of particles measuring 50 μm (0.05 mm) in diameter. This is much smaller than the size of sample that is normally considered acceptable for sampling for chemical analysis.
  3. DEAE cannot be detected in dry swabs or water moistened swabs from areas less than about 30 mm x 30 mm by the OC technique used in this analysis. The minimum area required to be swabbed in order to obtain a detectable amount of DEAE has not been determined conclusively, but areas measuring 4” x 5” (100 mm x 125 mm) on the acrylic glazing of “Salon Rose Roix” yielded a just barely detectable amount of DEAE so this would appear to be close to the area limit.
  4. DEAE and its reaction products are present in small concentrations on some surfaces, in some accretion layers, in some varnish layers, or in some paint layers, of some paintings in the IUAM collections. The amounts present are very small and do not appear to be uniformly distributed since they are not detected in all paintings.
  5. No sample analyzed appears to have been significantly changed by the presence of DEAE reaction products, although these products may be responsible for some of the effects attributed to DEAE contamination.
  6. In some paintings, water soluble components in or on the varnishes and paints, rather than DEAE reaction products from DEAE contamination, may be the prime cause of abnormal behaviours observed when some paintings are swabbed with water moistened swabs.

8. Recommendations for further work

The results of these analyses indicate that DEAE and its reaction products are present on some paintings. Some of the effects attributed to DEAE contamination may be due to the presence of water soluble components like starch or protein (glue, egg, etc.). Since the number of paintings examined for this report is so small, a true picture of the extent of the DEAE problem cannot be drawn. More paintings should be analyzed.

FTIR microspectroscopy is the quickest, most informative, and least intrusive technique to use for this analysis.

To clarify the extent of the effects of DEAE and the mechanism of its interaction with painting the following further work is recommended:

  1. Minuscule samples should be taken of varnishes and paints from many paintings that are apparently subject to DEAE contamination problems, for analysis by FTIR microspectroscopy, specifically for the presence DEAE esters and DEAE carboxylates, and for the presence of water soluble or water sensitive materials like starch and protein. This should quantify the number of paintings that are affected by DEAE and the extent of the DEAE problem.
  2. Test samples or model paintings should be exposed to DEAE vapors then analyzed by FTIR microspectroscopy to clarify the chemical reactions between painting media, DEAE, and DEAE reaction products. This has already been done to some extent in developing the FTIR microspectroscopic analysis procedure. The additional work needs to use more realistic exposure conditions such as exposure to a DEAE/air mixture of about 1% DEAE, rather than pure DEAE vapors or immersion in liquid DEAE. This would determine whether the interactions under less severe exposure conditions are the same as at the higher concentrations used in the FTIR analysis.
  3. Test samples or model paintings should be analyzed by microscopical methods, before and after exposure to DEAE, and before and after cleaning treatments to determine the physical or structural effects of DEAE exposure and subsequent cleaning of DEAE exposed paintings.
  4. The analysis reported here has shown that for some paintings, wiping with water moistened swabs removes water soluble compounds from the painting, including starch and protein (“Ste. Catherine”) and DEAE reaction products (“Green Trees”). Additional tests should be made to determine if swabbing with water moistened swabs is an effective treatment for removal of DEAE reaction products. DEAE reaction products are polar compounds and therefore soluble in polar solvents like water and alcohols. They are also surface active agents and therefore may be soluble in nonpolar solvents like aliphatic and low aromatic hydrocarbons such as mineral spirits or naphtha. Alkanolamine soaps such as those produced by reaction of monoethanolamine (MEA) with coconut or tall oil fatty acids show some solubility in these solvents. Analogous DEAE soaps with the increased hydrocarbon content due to substitution of the two hydrogens on the nitrogen of MEA by two ethyl groups will be even more soluble in these solvents. The effects of using these solvents to remove DEAE reaction products should be investigated. Using nonpolar solvents that may be less damaging to paintings than water, may be a valuable alternative.

8. References

ASTM Designation D 4983 – 89. “Standard Test Method for Cyclohexylamine, Morpholine, and Diethylaminoethanol in Water and Condensed Steam by Direct Aqueous Injection Gas Chromatography”, 8 pages.

Barret-Wilt, Gregory A Summary Report on Diethylaminoethanol Analysis, Indiana University, Chemistry Department, 1996.

Barrett-Wilt, Gregory A. Analysis of Art Works for Diethylaminoethanol (DEAE), Mass Spectrometry Facility, Chemistry Dept Indiana University. 1996.

Edgerton, S.A.; D.V. Kenny and D.S. Joseph. “Determination of Amines in Indoor Air from Steam Humidification”, Environ Sci. Tech., Vol. 23, 1989, pp. 484-488.

Fannick, Nicholas, Jane Lipscomb, and Kevin McManus. “Health Hazard Evaluation Report: HETA 83-020-1351, Johnson Museum, Cornell University, Ithaca, NY”, National Institute for Occupational Safety and Health Cincinnati, OH, August 1983, 14 pages.

Larrick, R.A. “Spectrophotometric determination of fatty amines in aqueous solution, Analytical Chemistry, Vol. 35, 1963, p. 1760.

Lester, Robert L. and David C White “Quantitative gas-liquid chromatographic analysis of ethanolamine, monomethyl ethanolamine, and dimethyl ethanolamine” Journal of Lipid Research, Vol. 8, 1967, pp. 565-568.

Malaiyandi, M and M.J. Goddard. “Development of Analytical Methodology and a Report
on Collaborative Study on the Determination of Morpholine, Cyclohexylamine, and Diethylaminoethanol in Aqueous Samples by Direct Aqueous Injection Gas Chromatography,” Journal of Testing and Evaluation, Vol. 18, No. 2, March 1990, pp. 87-97.

Malaiyandi, Murugan, Gordon H Thomas and Mary E Meek, “Sampling and Analysis of some corrosion inhibiting amines in steam condensates”, J Environ. Sci. Health, Vol.
A14(7), 1979, pp. 609-627.

Mayer, Ralph. The Artist’s Handbook of Materials and Techniques. 1982 Edition, Revised and Updated. (New York: Viking Press), p. 138.

Michelot, J, M.F. Moreau, J.C. Madelmont, P Labarre and G. Meyniel. “Determination of adiphenine, diphenylacetic acid and diethylaminoethanol by high-performance liquid chromatography,” Journal of Chromatography, Vol. 257, 1983, pp. 395-399.

Mifier, F.A., R.F. Scherberger, K S. Tischer, and A.M. Webber. “Determination of Microgram Quantities of Diethanolamine, 2-Methylaininoethanol, and 2-Diethylaminoethanol in Air,” Ameri can Industrial Hygiene Association Journal, 28:330-334, 1967.

Visscher, Susan M. “Longitudinal Studies of Indoor Air Pollution”, Submitted to the faculty of the Graduate School in partial fulfillment of the requirements of the degree Master of Science in the Department of Chemistry Indiana University February 1990. pp. 44-60.

Volent, Paula and Norbert S. Baer. “Volatile Amines Used as Corrosion Inhibitors in Museum Humidifications Systems”, The International Journal of Museum Management and Curatorship, Vol. 4, 1985, pp. 359-364.

White, Eldrige E. and Harold D. Swafford “Gas chromatographic determination of amine solubilizers and hydroxyl-containing solvent is electrocoat systems” in Nonpolluting Coatings and Coatings Processes, Proceedings of an ACS Symposium held August 30-31, 1972, in New York City, edited by J.L. Garden and Joseph W. Prane (New York: Plenum Press, 1973), pp. 93-107.

Williams, R. Scott. “The Composition of Commercial Prepared Artists’ Varnishes and Media”, Appendix A in Varnishes – Authenticity and Permanence, Workshop Handbook, (Ottawa: Canadian Conservation Institute), prepared by L. Carlyle and J. Bourdeau, 1994, 22 pages.

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