Influence of Date Palm Tree Fibers on the Tensile Fracture Energy of an Epoxy-based Adhesive

ABSTRACT

In the previous study, the effect of date palm fibers on the shear strength of adhesively bonded joints has been investigated by the same authors. Nevertheless, the role of these bio-based fibers on the fracture energy of adhesives has not been explored. The current study was conducted to comprehend the influences of date palm fibers on mode I fracture energy (G_Ic) of adhesives. To this aim, the fibers were collected from four different parts of a date palm tree (Bunch, Rachis, Petiole, and Mesh). After an alkalization treatment, they were cut into 0.5 to 2 mm and added to the adhesive in three various weight ratios (2, 5, and 10%). The fracture energy of the neat and reinforced adhesively bonded double cantilever beam (DCB) was then experimentally analyzed utilizing a compliance-based method. The outcomes prove the outstanding potential of the date palm fibers in enhancing the tensile fracture energy of adhesives. The highest improvement in G_Ic was achieved by 10 wt% Rachis fibers where the fracture energy of the enhanced adhesive was 7.6 times higher than the neat adhesive. The microscopic images of fracture surfaces revealed the significant roles of the considered fibers in the improvement of the G_Ic of the adhesive.

摘要

在之前的研究中, 相同的作者研究了枣椰纤维对粘接接头剪切强度的影响. 然而, 这些生物基纤维对粘合剂断裂能的作用尚未探索. 本研究旨在了解枣椰纤维对粘合剂I型断裂能 (GIc) 的影响. 为此, 从枣树的四个不同部位 (束, 轴, 叶柄和网) 收集纤维. 经过碱化处理后, 将它们切成0.5至2mm, 并以三种不同的重量比 (2, 5和10%) 添加到粘合剂中. 然后, 利用柔度法对整齐和加固的粘结双悬臂梁 (DCB) 的断裂能进行了实验分析. 研究结果证明了椰枣纤维在提高胶粘剂拉伸断裂能方面的巨大潜力. GIc的最大改善是通过10 wt%的轴纤维实现的, 其中增强型粘合剂的断裂能是纯粘合剂的7.6倍. 断裂表面的显微图像揭示了所考虑的纤维在改善粘合剂GIc方面的重要作用.

KEYWORDS:

• Mode I fracture energy
• date palm fibers
• reinforced adhesive joints
• bio-based fibers
• DCB
• failure mechanisms

Disclosure statement

No potential conflict of interest was reported by the author(s).

Highlights

• The effect of date palm fibres on the fracture energy of adhesive joints is studied.

• Various types and weight ratios of fibres are considered.

• A remarkable enhancement in mechanical properties of reinforced samples were observed.

• The maximum improvement in tensile fracture toughness was 666%.

• Fracture surface analysis showed the significant contribution of the fibers in joint strength.