Dynamic mechanical spectroscopy of paper

The viscoelastic properties of base-stock and coated papers are conveniently evaluated using DMA in a film-tension mode. Measurements of storage modulus (E′) and loss modulus (E″) give good reproducibility and yield distinct patterns for paper types. Factors that mediate paper strength in the production environment can be simulated using DMA. Analysis of the individual components, base paper, latex and coated paper gives significant insights into the composite nature of paper. Measured glass transitions in papers with mixed coatings give characteristic peaks that are attributable to the pure latex Tg’s. SEM photomicrographs show changes in surface morphology for coated papers and provide supportive data for DMA.