Coupled hydro-mechanical aging of short flax fiber reinforced composites

Abstract

One of the challenges in the widespread use of biocomposites for engineering applications is the influence of environmental conditions on their mechanical properties, particularly for a combination of aging factors such as temperature, moisture, and mechanical stresses. Thus, the purpose of this paper is to study the influence of coupled aging factors by focusing on a 100% bio-based and biodegradable composites made of flax/poly(lactic acid) with several fiber contents. The development of a specific testing setup enabled continuous in-situ measurements and allowed comparing the effects of combined aging factors to those of uncombined aging factors. It was confirmed that the aging temperature in wet conditions led to a loss of elastic properties, especially for higher fiber fractions. While creep tests in dry conditions resulted in little decrease of elastic properties, it was observed that mechanical loading of the materials combined with water immersion resulted in a strong synergistic effect on the loss of stiffness. Finally, the presence of fibers reduced environmental stress cracking mechanisms and increased the time to failure.

Two-year performance study of porous, thermoset, shape memory polyurethanes intended for vascular medical devices

“…As mentioned previously, aging of materials is associated with a number of property changes, and some polyurethane systems have demonstrated spectroscopic indicators of these changes in addition to loss of physical properties [12][13][14][15][16][17][18]. Acceleration of porous, segmented polyurethane aging was shown to decrease hydrogen bonding as a result of rearrangement of the hard segments.…”

Ageing of autoclaved epoxy/flax composites: Effects on water absorption, porosity and flexural behaviour

“…The hydrophilic nature of the fibres (with resultant water uptake) and the poor fibre-matrix bonding were also other significant factors that contributed to the reduction of the mechanical performance. Regazzi et al [17] examined the influence of thermohydromechanical-based ageing on the elastic behaviour of flax/poly (lactic acid) composites. The results confirmed that the ageing temperature in wet conditions led to a loss of the elastic properties.…”

Synergistic Utilization of Flax Fiber Polymer Composites: A Review

“…When the temperature increases more than 55 0 C it showed major negative effects so it is recommended to utilize the hybrid composite for lesser temperature application. Aging behaviour of flax fiber composite on their mechanical properties was reported [25]. The major effects due to the environment manipulate of the Fiber is mainly squabble about the mechanical stress, temperature and moisture, this study helped to understand the behaviour of flax with lactic acid for different percentage.…”