Experimental assessment of the improved properties during aging of flax/glass hybrid composite laminates for marine applications

Abstract

The investigation for natural fibers composites in terms of performance, durability, and environmental impact for structural applications in marine environments is a relevant challenge in scientific and industrial field. On this context, the aim of this work is to assess the durability and mechanical stability in severe environment of epoxy/glass–flax hybrid composites. For the sake of comparison, also full flax and glass epoxy composites were investigated. All samples were exposed to salt–fog environmental conditions up to 60 aging days. Wettability behavior during time was compared with water uptake evolution to assess water sensitivity of hybrid composite configurations. Moreover, quasi‐static flexural and dynamic mechanical analysis were carried to evaluate as aging conditions, laminate configuration influence the surface and mechanical performances stability of the hybrid composites. The addition of glass fibers on flax laminate allows to enhance both flexural strength by 90%, and modulus by 128%, even if these properties are lower than those of full glass laminates. The results evidenced that the hybridization of flax fibers with glass ones is a practical approach to enhance the aging durability of epoxy/flax composite laminates in marine environmental conditions, obtaining a suitable compromise among environmental impact, mechanical properties, aging resistance, and costs. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 47203.

Hybrid and Nonhybrid Laminate Composites of Sugar Palm and Glass Fibre-Reinforced Polypropylene: Effect of Alkali and Sodium Bicarbonate Treatments

“…In the case of the hybrid composites, an intermediate value of the contact angle in the range of 83.4°to 89.1°was observed. This shows that SPF is hydrophilic in nature due to its structure, and, subsequently, its plays a major role on water absorption sensitivity [50]. Table 4.…”

Pinned Hybrid Glass-Flax Composite Laminates Aged in Salt-Fog Environment: Mechanical Durability

“…The presence of six internal laminae reinforced with hydrophilic flax fibers in the stacking sequence can be considered the main cause of the high water absorption evidenced by hybrid laminates (~6% [19]) during the salt-fog exposition. Furthermore, the water diffusion into the laminate is also influenced by matrix voids and micro cracks due to aging environmental exposure and/or the manufacturing process that speed up the phenomenon [44].…”

“…In fact, it is well known that the performances reduction of GFRP (Glass Fiber Reinforced Plastics) composites in wet condition stabilizes after moisture saturation level [18]. Calabrese et al [19] showed that the hybridization of lignocellulosic flax fibers with glass ones represents an effective and suitable compromise in terms of environmental impact, mechanical properties, aging resistance, and cost between flax and glass composites, for its use in marine applications. Analogously, Saidane et al [20] evidenced that the water uptake and diffusion are limited by the addition of glass fiber layers to flax laminates.…”

Dynamic Mechanical Behavior Analysis of Flax/Jute Fiber-Reinforced Composites under Salt-Fog Spray Environment

“…Natural fiber-reinforced composites (NFRPs) have received growing attention in the last decades, both from the academic world and from industries, thanks to their specific mechanical properties, reduced cost and advantages for health and recyclability. Nevertheless, this class of innovative materials shows also some drawbacks, such as their limited aging resistance in humid or wet environmental conditions, i.e., an extensive literature shows that NFRP materials experienced dramatic degradation of their quasi-static mechanical properties when exposed to these environments [10][11][12][13][14][15][16][17][18]. This can be partially ascribed to the softening and plasticization phenomena of natural fibers and thermoset matrix [19,20].…”