Degradation of aramid fibers under alkaline and neutral conditions: Relations between the chemical characteristics and mechanical properties

• Published in: Journal of applied polymer science Vol. 116; no. 5; pp. 2504 - 2514
• Main Authors: Derombise, G, Van Schoors, L. Vouyovitch, Davies, P
• Format: Journal Article
• Language: English
• Published: Hoboken Wiley Subscription Services, Inc., A Wiley Company 05-06-2010; Wiley
• Subjects: ageing; Applied sciences; Aramid fibers; Cables; Degradation; Engineering Sciences; Exact sciences and technology; Fibers; Fibers and threads; Forms of application and semi-finished materials; Materials; Polymer industry, paints, wood; Reinforcement; Reproduction; Sea water; structure-property relations; Technology of polymers; Tensile strength; viscosity; ageing; Nylon; fibers; Thermal ageing; Synthetic fiber; Aromatic polymer; Mechanical properties; Tensile property; degradation; Chemical degradation; Experimental study; Marine environment; Hydrolysis resistance; structure-property relations; viscosity; Aqueous medium; Aramid fiber; Basic medium; Property structure relationship; Chemical properties; Exposure time; Rheological properties; VIEILLISSEMENT; PROPRIETE MECANIQUE; POLYMERE; HYDROLYSE; FIBRE ARAMIDE; PROPRIETE CHIMIQUE; LONG TERME; DEGRADATION; FIBRE
• ISSN: 0021-8995; 1097-4628; 1097-4628
• DOI: 10.1002/app.31145

Aramid fibers are high-performance materials that have been used in various applications such as heat and cut protection, composites, rubber reinforcement, ropes and cables, and fabrics; today their use is proposed in geotextiles for alkaline ground reinforcement, and they have been used in cables for marine applications for a few years. However, there is a lack of experience with the long-term behavior of aramid fibers in wet and alkaline environments. Aging studies were therefore performed on Twaron 1000 fibers under different conditions (sea water, deionized water, pH 9, and pH 11). Hydrolytic degradation was evaluated with Fourier transform infrared and viscosimetry measurements, which were correlated with tensile test measurements. The tensile strength followed a logarithmic evolution with the aging time, whereas the modulus remained constant. A linear relation between the tensile strength and the reduced viscosity of the hydrolytically aged fibers is highlighted. Aging indicators are proposed that allow the hydrolytic degradation to be quantified.