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The Effect of Folding on the Internal Structure of Ballistic Fibers



Haruki Kobayashi, Walter G. McDonough, Hae-Jeong Lee, Jae H. Kim, Amanda L. Forster, Kirk D. Rice, Gale A. Holmes


In one of our previous studies, the mechanical properties of poly (p-phenylene benzobisoxazole) (PBO) fibers were degraded when the fibers were folded. When we examined poly (p-phenylene terephthalamide) (PPTA) fibers, we did not find a similar drop in mechanical properties. In the present study, we investigated the possibility of structural changes caused by folding in PBO and PPTA fibers by using small angle X-ray scattering (SAXS). From our findings, we postulate that the fibrils in the PBO fibers were subdivided when the fibers were folded whereas the PPTA fibrils did not seem to change. The subdivision for PBO fibers may create new surfaces and defects inside the fibers. Thus, the subdivision may influence not only mechanical properties, but also hydrolytic degradation and other failure pathways.
Proceedings Title
SAMPE 2011
Conference Dates
May 23-26, 2011
Conference Location
Long Beach, CA, US


PBO, SAXS, PPTA, ballistic fibers


Kobayashi, H. , McDonough, W. , Lee, H. , Kim, J. , Forster, A. , Rice, K. and Holmes, G. (2011), The Effect of Folding on the Internal Structure of Ballistic Fibers, SAMPE 2011, Long Beach, CA, US, [online], (Accessed May 18, 2024)


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Created May 25, 2011, Updated October 12, 2021