Paper preservation with polyamidoamines: a preliminary study

This research deals with the use of water soluble polyamidoamines (PAAOH’s) as innovative paper preservatives endowed with deacidification and biostatic properties. They were obtained by reaction of N,N-methylenbisacrylamide (MBA) with ethanolamine (EA) and were characterized by Fourier Transform Infrared Spectroscopy analysis (FTIR), Electrospray Mass Spectrometry (ESI-MS) and Nuclear Magnetic Resonance (NMR). PAAOH’s should tightly bind to cellulose through a network of H-bonds, as suggested by molecular mechanics calculations. Actually, FTIR analysis and the increment in anhydrous mass of paper samples demonstrated that PAAOH’s were progressively absorbed by paper cellulose without altering the original color of paper as observed by colorimetric analysis. The deacidifying effects were confirmed by significant increment in pH values of paper after treatment in comparison to the untreated paper samples. In vitro antibiogram assay showed a good but variable biostatic effect on different fungal test strains, depending by species, PAAOH’s concentration and pH in the substrate.