Investigation of the Effect of Cupric Chloride on Thermal Stabilization of Polyamide 6 as Carbon Fiber Precursor

KARACAN I. , Baysal G.

FIBERS AND POLYMERS, vol.13, no.7, pp.864-873, 2012 (Journal Indexed in SCI) identifier identifier

  • Publication Type: Article / Article
  • Volume: 13 Issue: 7
  • Publication Date: 2012
  • Doi Number: 10.1007/s12221-012-0864-7
  • Title of Journal : FIBERS AND POLYMERS
  • Page Numbers: pp.864-873


An investigation on the role of cupric (Cu2+) ion incorporation during the thermal stabilization of polyamide 6 fibers was carried out using a combination of differential scanning calorimetry (DSC), thermogravimetric analysis (TGA) and X-ray diffraction (XRD) measurements. Cupric chloride pretreated and thermally stabilized polyamide 6 (PA6) fibers was characterized by a reduction in fiber diameter and linear density values together with color changes from light brown to black with increasing stabilization time. PA6 fibers were properly stabilized after 8 h of stabilization time prior to carbonization. The results obtained from DSC and TGA measurements indicated that there was an improvement in the thermal stability when cupric (Cu2+) ions were incorporated into the polymer structure. TGA thermograms showed the relative improvement in thermal stability as indicated by increasing char yield with progressing time. Char yield reached a maximum value of 33.6% at 1000 degrees C for the cupric chloride pretreated PA6 fibers stabilized for 12 h at 180 degrees C. Experimental results obtained from DSC and X-ray diffraction methods suggested the loss of crystallinity as a result of perturbation of hydrogen bonds with progressing time. The formation of cupric ion-amide coordination bonds improved the thermal stabilization by encouraging the development of ladder-like structures. The investigation resulted in a new method of evaluation of X-ray stabilization index specifically intended for the thermally stabilized PA6 fiber.