THE INFLUENCE OF OLIGOMERIC MELAMINE RESIN ON BOOKBINDING RESISTANCE TO ENVIRONMENTAL FACTORS

This paper aims to study the influence of the environmental factors upon the ageing resistance characteristics of bookbinding leather treated with an oligomeric melamineformaldehyde resin modified by benzenesulfonation (BSMF). Leather treated with 0.25 g BSMF as dry matter (DM)/g leather acquired significant hydrothermal and dimensional stability to environmental factors, compared with the untreated leather, when subjected to identical accelerated ageing parameters (T = 50oC, RH = 90% for 24h, SO2 concentration in air = 0.04 mg/L). FTIR-ATR spectra and SEM images of treated leather indicated a minimal damage of the collagen structure: crosslinking bridges between resin and collagen functional groups proved to be stable to the accelerated ageing conditions, which must be assigned to the BSMF product ability to slow down the acid hydrolysis processes. This is related both to the crosslinking ability of BSMF between the collagen macromolecule chains and to its acid buffer behaviour.