EVALUATION OF SOLID-PHASE MICROEXTRACTION ON-FIBER DERIVATIZATION FOR THE ANALYSIS OF PAPER DEGRADATION COMPOUNDS
Abstract
As a contribution to exploring non-destructive strategies for the evalua-
tion of the state of degradation of paper documents, two SPME on-fiber
derivatization methods were developed for the analysis of low molar
mass carbonyl and carboxyl compounds formed during paper degrada-
tion upon ageing. The two SPME methods involved the specific extrac-
tion of carbonyl and carboxyl compounds using PFBHA and PDAM as
derivatizing agents, respectively. They were first tested and validated in
headspace sampling mode where the emission from a groundwood pulp
paper was characterized qualitatively and quantitatively. The methods
were then applied on a set of four papers of different composition and
degradation state obtained by artificial ageing. The second step was
aimed at extending the methodology for field application and involved
the development of direct contact sampling of the VOCs emitted from
four books of different composition, naturally aged, by inserting the
derivatized SPME fibers inside the books core.
The analyses are discussed in the light of the paper’s pulp composition
and their degradation state related to the artificial ageing. The results
showed that there was a close relation between the amount of VOCs
emitted from paper and the composition of the paper, and that the gen-
eral trend for both acids and aldehydes was an increase in the emissions
with ageing time, or occasionally, a plateau reached at the longest age-
ing times. The VOCs emitted by the naturally aged books were consistent
with those of the artificially aged papers. Globally the emissions of alde-
hydes were much lower than the emissions of acids and, for all the
papers the most abundant VOC was formic acid, both in the unaged and
in the aged samples. This is noteworthy as formic acid has been recently
designated as highly aggressive towards cellulose.