Accession Number:

ADA422638

Title:

Dynamic Studies in Fiber Processing

Descriptive Note:

Final rept. 1 Jul 2000-31 Dec 2003

Corporate Author:

STATE UNIV OF NEW YORK AT STONY BROOK DEPT OF CHEMISTRY

Personal Author(s):

Report Date:

2004-02-18

Pagination or Media Count:

18.0

Abstract:

The structural development of a nanocomposite, containing 95 wt isotactic polypropylene iPP and 5 wt modified carbon nanofiber MCNF, during fiber spinning was investigated by in-situ synchrotron small-angle X-ray scattering SAXS and wide-angle X-ray diffraction WAXD techniques. The modification of carbon nanofibers CNFs was accomplished by a chemical surface treatment using in-situ polymerization of olefin segments to enhance its compatibility with iPP. The iPPMCNF nanocomposite was prepared by a two-step blending process in order to ensure the exfoliation of MCNF. X-ray results showed that at low spin-draw ratios, the iPPMCNF nanocomposite fiber exhibited much higher iPP crystalline orientation than the control pure iPP fiber. At higher spin-draw ratios, the crystalline orientation of the nanocomposite fiber and that of the pure iPP fiber was about the same. The crystallinity of the composite fiber was higher than that of the control iPP fiber, indicating the nucleating effect of the modified carbon nanofibers. The nanocomposite fiber also showed larger long periods at low spin-draw ratios. Measurements of mechanical properties indicated that the nanocomposite fiber with 5 wt MCNF had much higher tensile strength, modulus and longer elongation to break. The mechanical enhancement can be attributed to the exfoliation of MCNF in the matrix, which was confirmed by SEM results.

Subject Categories:

  • Refractory Fibers
  • Laminates and Composite Materials

Distribution Statement:

APPROVED FOR PUBLIC RELEASE