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Abstract

High performance organic fibers such as Kevlar, which are highly fibrillar in nature, possess excellent mechanical properties under tension but exhibit very poor strength in compression due to poor interfibrillar attraction. This study involves infiltrating polymeric materials into single aramid filament networks to improve interfibrillar adhesion and thus modify their mechanical properties. Wet-never-dried aramid fibers are used in this study, but it is still necessary to further open the fibrillar network with concentrated sulfuric acid to effectively infiltrate the polymer. While there is significant improvement in tensile strength after polymer infiltration, this is offset by a loss in strength due to the acid treatment. However, there is a significant increase of over 33% in compressive strength as a result of infiltration. The infiltration technique shows excellent promise and could be used for tailoring the properties of fibers with fibrillar morphology for selective end-use applications.

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Mechanical Property Modification of Aramid Fibers by Polymer Infiltration

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