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Title: Impurities in Kevlar 49 fibers

Conference ·
OSTI ID:5994840

The impurities in Kevlar 49 fibers (poly(p-phenylene terephthalamide)PPTA) are reported and discussed in terms of the fiber fabrication processes. These impurities were monitored by inductively coupled plasma emission and optical emission spectroscopy. The principal impurities Na/sub 2/SO/sub 4/ and total S were analyzed chemically. From these chemical analyses together with C, N, H elemental analyses we show that there are 1.5 wt % impurities present in Kevlar 49 fibers of which approx. 50% are in the form of Na/sub 2/SO/sub 4/ and the remainder probably in the form of benzene sulfonic -SO/sub 3/H PPTA side groups. There are 3 of these acid groups per each PPTA macromolecule. Organic impurities, such as terephthalic acid are discussed in the light of degradation studies of PPTA-H/sub 2/SO/sub 4/ spinning dopes. Electron microprobe x-ray spectroscopy and laser-induced damage studies were utilized to investigate the distribution of impurities through the fiber cross-section. The distribution of impurities throughout the fiber are determined by the fiber fabrication processes and are discussed at the microscopic and molecular level. The defects caused by these impurities and their effect on the deformation and failure modes are also considered. 22 references, 3 tables.

Research Organization:
Lawrence Livermore National Lab., CA (USA)
DOE Contract Number:
W-7405-ENG-48
OSTI ID:
5994840
Report Number(s):
UCRL-90947; CONF-850323-2; ON: DE85004996
Resource Relation:
Conference: 30. national meeting of the Society for the Advancement of Material and Process Engineering, Anaheim, CA, USA, 19 Mar 1985; Other Information: Portions are illegible in microfiche products
Country of Publication:
United States
Language:
English