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Canadian Conservation Institute
Helen Burgess
Nancy Binnie
Period of Activity: 6/86 to 6/89
Project Abstract
This study investigated the potentially harmful interaction
between Vikane (sulfuryl fluoride) and cellulose, starch and lignin-containing
materials. Changes in percent reflectance are reported after accelerated
aging at 70 °C and 50% relative humidity. Results were also
obtained for average degree of polymerization, nitrophenylhydrazone
carbonyl content, total acidity (by iodometry), extracted and surface
pH, and tensile strength (Instron). The set of exposed samples numbered
25 groups of paper and textile fibers containing cellulosic and
ligneous fibers.
Major Findings
The analysis of exposed papers has been finished. For paper
then, the following interpretation of the data holds. Fumigation
with normal grade Vikane causes an immediate large decrease in the
alkaline reserve of buffered papers and a significant increase in
acid in fibers which have an initial pH in the slightly alkaline
to slightly acid pH range. Papers containing lignin show a development
in acid functional groups in the following order: "old" ligneous
papers >> "new" newsprint newsprint; > moderately aged,
circa 1930. Age and fiber content also influence the results for
the rest of the papers. The DP data go along with changes in the
level of oxidation and increased acidity, namely that four of the
eight fibers analyzed show that Vikane is causing a very large,
significant drop in the average polymer length, which is detectable
only after accelerated aging. The papers that did not change were
either buffered or their DPwas already so low that further degradation
is progressing at too slow a rate to be detectable. The implication
here is that acid-catalyzed depolymerization is an important mechanism
of the deterioration of paper fiber by Vikane. Fluoride levels are
also elevated above background (control samples) especially for
buffered papers and those with gelatine sizing but the causes for
these values are somewhat uncertain. Results for XRM-5162 Vikane
(with acidic impurities removed) have not been determined.
Primary Publications
Derrick, M. R., H. D. Burgess, M. T. Baker, and N. E. Binnie,
"Sulfuryl Fluoride (Vikane®): A Review of Its Use as a Fumigant,"
Journal of the American Institute for Conservation,Vol. 29, 1990,
pp. 77-90.
ABSTRACT-See same listing under project 1.3.
Burgess, H. D., and N. E. Binnie, "The Development of a Research
Approach to the Scientific Study of Cellulosics and Ligneous Materials,"
Journal of the American Institute for Conservation, Vol. 29, 1990,
pp. 133-152.
ABSTRACT-The evaluation of scientific results and recommendations
in the conservation literature is greatly aided by a good understanding
of the rationale behind the selection of test materials and methods.
Unfortunately, space rarely permits the authors to fully explain
such important issues as how the chemistry of the system under study
has influenced their approach to the selection of analytical methods;
the extent to which these experimental procedures can be expected
to yield the desired information; and how closely the scientific
model approximates the "real life" situations that the conservator
meets in his or her laboratory. The authors have taken this opportunity
to present their design considerations because the Vikane®
project is one of the most complex and broadly based projects ever
carried out in the field of paper and textiles by the Canadian Conservation
Institute, involving some twenty-five separate fiber types ranging
from modern to circa 1622, and nine different analytical procedures.
Druzik, J. R., H. D. Burgess, M. T. Baker, and M. R. Derrick, "Laboratory
Investigation of the Fumigant Vikane®," American Chemical Society,
Division of Environmental Chemistry, Miami, Florida, September 10-15,
1989.
ABSTRACT-See same listing under project 1.3.
Burgess, H. D., and N. E. Binnie, "The Effect of Vikane®
on
the Stability of Cellulosic and Ligneous Materials-Measurement of
Deterioration by Chemical and Physical Methods," Materials Issues
in Art and Archaeology II, Vol. 185, 1991, Proceedings of the Materials
Research Society, Spring Meeting, San Francisco, California, April
16-20, 1990.
ABSTRACT-Vikane (sulfuryl fluoride) is a commercial fumigant which
is used for the control of pests in museum collections. This paper
summarizes the results obtained through an investigation of the
effect of Vikane on 25 paper and textile samples. Samples chosen
were representative of artifacts present in North American collections;
(cotton, linen, jute, and wood pulp fibers, from 1622 to present).
The effect of the fumigation treatment has been evaluated by chemical
and physical analyses: (1) Acidity-surface pH, cold extraction pH,
total acid (iodometric titration), (2) Oxidative and Hydrolytic
Degradation-viscometric average degree of polymerization, carbonyl
content (hydrazone derivitization) and (3) Fumigant Residues (specific
ion electrode) Analysis of unfumigated and fumigated samples was
carried out before and after accelerated aging(70 °C and 50%
relative humidity) in order to estimate the long-term stability
of fumigated samples.
The data obtained show that commercial grade Vikane®
degrades
cellulose and ligneous fibers. A second set of experiments on two
fiber types using an experimental grade of Vikane®
(XRM-5162);
gave significantly less degradation. The presentation of this work
concentrates on a general scientific interpretation of the results.
It is anticipated that the conclusions will be applicable to a broad
range of artifacts.
Baker, M. T., H. D. Burgess, N. E. Binnie, M. R. Derrick, and J.
R. Druzik, "Investigation of the Fumigant Vikane®
" Preprints,
ICOM 9th Triennial Meeting, Vol. 2, Dresden, August 26-31, 1990,
pp. 804-811.
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