Analysis of the Mechanical Strength of Polymeric Composites Reinforced with Sisal Fibers

ABSTRACT

This work focused on the evaluation of the mechanical strength of sisal fiber reinforced composites panels in view of using vacuum infusion processing method. The most recent market requirements are green material, which is sustainable and eco-friendly. The polymer used in the composite matrix is a polyurethane derived from castor oil and therefore, fits in the concept of green material, for its renewable source and solvent-free production method. The vacuum infusion of the polymer within a sealed bag is a production method that avoids/reduces the formation of bubbles within the mold, which in turn can produce composite panels with higher values of mechanical strength. For the evaluations in this work, several panels were produced with the different architecture of fabrics. The variations consisted of the production of aligned fibers; one-layer of plain weave fabric and three-layers of plain weave fabric. Mechanical strength was evaluated by means of tensile test and flexural three point bending tests; the morphology of the fracture surface was evaluated by SEM images. The tensile strength of the panels resulted in values of 146.34 MPa, 9.19 MPa and 15.87 MPa for aligned, one-layer, three-layers panels, respectively. The flexural strength resulted in values of 23.23 MPa for three-layers panels.

摘要

本文从真空浸渍法的角度对剑麻纤维增强复合材料板材的力学性能进行了评价.最新的市场需求是绿色材料，这是可持续和环保的.复合材料基体中使用的聚合物是由蓖麻油制成的聚氨酯，因此，由于其可再生来源和无溶剂生产方法，符合绿色材料的概念.在密封袋中真空注入聚合物是一种避免/减少模具内气泡形成的生产方法，进而可以生产具有较高机械强度值的复合板.为了在这项工作中进行评估，生产了几种不同结构的织物面板.这些变化包括生产排列整齐的纤维一层平纹织物和三层平纹织物.采用拉伸试验和弯曲3点弯曲试验评价了材料的力学强度，并用扫描电镜图像对断裂表面形貌进行了评价.面板的拉伸强度分别为146.34兆帕、9.19兆帕和15.87兆帕.三层面板的弯曲强度值为23.23MPa.

KEYWORDS:

• Composite panels
• vacuum infusion
• sisal fibres
• tensile strength
• flexural strength
• SEM images

关键词:

• 复合板
• 真空输液
• 剑麻纤维
• 拉伸强度
• 抗弯强度
• 扫描电镜图像

Acknowledgments

Author acknowledges CAPES, CNPq, Araucária Foundation, CMCM central analysis of UTFPR-CT for awarded funds, which enabled the activities of this project.