The Chemistry of Paper Preservation Part 3. The Strengthening of Paper
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Henry A. Carter [1]
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[1] Augustana University College, Canada
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- Localización: Journal of chemical education, ISSN 0021-9584, Vol. 73, Nº 12 (December), 1996, págs. 1160-1162
- Idioma: inglés
- Texto completo no disponible (Saber más ...)
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Resumen
The following study describes the parylene and graft copolymerization processes that have been developed to strengthen fragile or brittle paper artifacts. Theparylene process involves vaporizing di-para-xylylene at 150o - 250 oC and splitting the dimeric parylene gas at 650o - 690 oC to mono-para-xylylene. The monomer vapor collides with the surface of the paper sample at room temperature and penetrates the cellulose fibers. Polymerization of the monomeric units to poly- para-xylylenes then occurs with the deposition of a thin uniform film. This parylene film forms mechanical links with broken fibers and strengthening occurs. The graft copolymerization (British Library) method involves treating papers with gaseous monomeric ethyl acrylate and methyl methacrylate, and initiating copolymerization by irradiating the papers with low intensity gamma rays. Webs of long-chained polymers are deposited on and between the cellulose fibers thereby strengthening the papers. The chemistry as well as modifications to both processes are discussed.
