Correlations between creep, shrinkage, and dynamic mechanical characteristics of magnetic tape materials

Creep compliance, shrinkage, and dynamic mechanical analysis (DMA) results are presented and discussed for developmental magnetic tapes made from PEN and metalized PET (Spaltan®) substrates as well as PEN substrate samples cut from wide-stock in the machine and transverse directions. Curve fit parameters from the Kelvin-Voigt model are discussed to shed light on the creep-compliance characteristics, particularly the roll-off characteristics observed at elevated temperatures and long time periods. Characteristic peaks observed in storage and loss moduli measured using DMA that correspond with molecular movement provide information that assists with the understanding of creep-compliance and shrinkage behavior for these materials. Such movement corresponds with dimensional instabilities that need to be understood for future generations of advanced digital magnetic tapes. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011