VARTM을 공법을 통한 JFRP의 계면처리 효과에 따른 기계적 특성에 대한 연구

Abstract

Abstract

The jute is among the best of natural fibers in terms of tensile strength and availability. So jute fibers were used by VARTM (Vacuum Assisted Resin Transfer Molding) with silane coupling agent to make stronger JFRP(Jute Fiber Reinforced Plastic).

The purpose of this study was to determine the mechanical properties of epoxy resins and jute fiber as composites and to determine their validity. For this, the JFRP was made using VARTM and hand lay-up. This work evaluated the mechanical properties of the composites according to various manufacturing processes. The specimens made using the two methods were investigated using the tensile test and short-beam test. The specimen made by VARTM is stronger than that made by hand lay-up.

The introduction of a coupling agent distinctly influenced the mechanical properties of the composites. The strength of the specimen using a silane coupling agent eventually became stronger than the specimen without a silane coupling agent. Whether the JFRP was washed by alkali before use with coupling agent affected its mechanical properties, such as tensile strength and short-beam strength.

Using hand lay-up, VARTM, and a silane coupling agent, the jute fiber of volume fraction was checked by specimens. First, the jute fiber’s weight was measured, and then the weight of the JFRP was confirmed. On the basis of the experiments, the hand lay-up, VARTM, and coupling agent were measured using the percentage formula. The specimens made using VARTM had a higher jute fiber percentage than those made by hand lay-up, but there was no difference regarding the existence of silane in the VARTM process.

The tensile fracture surface of each specimen was confirmed by SEM. The specimens made by hand lay-up, VARTM and washed and not by alkali before being used silane coupling agent were examined respectively for the observing interfacial adhesion from the covalent bond between the fiber and the matrix. Using the specimens observed by SEM, the difference of the strength of the specimens was investigated. In the case of the JFRP washed by alkali, the silane coupling agent improved interfacial adhesion from the covalent bond between the fiber and the matrix.