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Long term stability of ultra high molar mass polyethylene fibres



Amanda L. Forster, Aaron M. Forster, Joannie W. Chin, Sylvain H. Petit, Kai-Li Kang, Nicholas G. Paulter Jr., Kirk D. Rice, Don Jenket II, Mohamad Al-Sheikhly


Abstract. The performance of ultra-high molar mass polyethylene (UHMMPE) fibres for ballistic protection is predicated on the development of a highly aligned molecular structure that allows the polymer to exhibit a superior strength in the axial direction of the fibre. Body armour manufacturers have exploited the inherent strength of these materials to develop body armour that continues to defeat ever-increasing ballistic threats. However, even an ideal molecular structure will be subjected to degradation during use, which can reduce the high strength of these fibres, and impact their ability to protect the wearer. In this work, the long term stability of UHMMPE fibres is investigated by exposing yarns to temperatures of 43, 65, 90, and 115 Celsius for periods of time up to 81 weeks, and monitoring the tensile strength of the yarns. The activation energy for this ageing mechanism was calculated to be approximately 140 kJ/mol. Changes in the oxidation index of this material due to ageing were also studied using Fourier Transform Infrared Spectroscopy (FTIR), and these changes are compared with changes in tensile strength. The effect of ageing on the morphology of the fibres is also studied using thermal analysis and X-ray diffraction (XRD) methods.
Proceedings Title
Personal Armour Systems Symposium
Conference Dates
September 19-23, 2016
Conference Location
Amsterdam, NL
Conference Title


Forster, A. , Forster, A. , Chin, J. , Petit, S. , Kang, K. , Paulter Jr., N. , Rice, K. , Jenket II, D. and Al-Sheikhly, M. (2016), Long term stability of ultra high molar mass polyethylene fibres, Personal Armour Systems Symposium, Amsterdam, NL (Accessed April 14, 2024)
Created September 19, 2016, Updated March 20, 2023