The Relation Between Compressive Visco-elastic Behavior of Carpets and Pilling up State of Constitute Fibers

Abstract

Apparent compressive complex modulus of commercial carpets at a wide range of given compressive strains have been measured by means of Hysteresis loop meathod with a specially designed apparatus at a fixed frequency of 0.2 Hz.
The values of the modulus may be caluculated on the assumption that the mechanical model of the carpet is simillar to that of Voigt model.
The values of apparent compressive complex modulus of used commercial carpets resemble these of rubberlike materials untile the compressive strains of about 50%.
ε_c, (F_f.c=0.5) is determined specially strain when the volume fraction of the fibers in the carpet reaches 0.5.
With the progress compression, when the compressive strain reaches ε_c (F_f.c=0.5) the values of apparent storage modulus for the carpets nearly equal to 5×10⁸ dyne/cm, ². which is generally known as the value of modulus for leathery material. At the near strains of ε_c (F_fx=0.5), the values of apparent compressive complex modulus of the cararts increase rapidly with increasing applied compressive strain.