الفهرس 
IntroductionOnly 14 pages are availabe for public view
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Abstract
This exploratory study shows that recycling short discrete residual flax fibers –in the form of fabric- has promising results for producing natural yarn reinforced polyester (NYRP) laminates. Accordingly, the following points can be initially concluded for the explored NYRP laminates: 1- In case of using polyester as matrix the water absorption ratio of the laminates is significantly reduced with respect to the original ratio of the flax fabric with no remarkable effect on the density of polyester. 2- Some physical defects were observed -under microscope- in NYRP specimens such as air bubbles and incomplete impregnation as well as bad distribution of fibers. Manufacturing process is the main cause of these defects in addition to the possible influence of using natural twisted-form yarns. 3- Remarkable tensile and flexural stiffening was observed for the flax-fabric-polyester composite compared to pure polyester. This stiffening reached 3.4 folds under tension and 3.8 folds under flexure depending on the manufacturing process and/or the direction between the applied load and the fiber alignment. 4- Even though tensile strength, ductility and toughness enhancement were clear in tension of the explored NYRP laminates compared to pure polyester. However, in case of single layer laminate the premature failure of the NYRP specimens is the reason for this lowering the flexure strength. This premature failure can be related to either the aforementioned defects- and/or loading-fiber directions influence. It’s expected that the sensitivity of single-layer laminate has a significant role on the very early premature failure cases; therefore, in this study the focus was on the performance of the multilayered NYRP laminate.