Study on jute epoxy composite properties made by vacuum assisted resin infiltration (VARI) technique

Natural fiber composite research is of prime importance nowadays because of the environmental concern and lowering the cost of the product in relation with its usage. Raw Bangla white grade B jute – epoxy composites were made using Vacuum Assisted Resin Infiltration (VARI) technique and hand lay-up. Fiber impregnation was studied by SEM. Longitudinal and transverse three point bend tests were performed to evaluate the interfacial characteristics of unidirectional (UD) jute epoxy composite. It was observed that with low volume fraction (<35%) of jute the composite efficiency obtained is only below 60% of the theoretical value when using the VARI process. SEM observation of the fracture surface clearly showed the resin penetration inside the jute fiber lumen regardless of the resin front direction within the fibrous preform and the resin cured inside the lumen has a surface texture like the lumen interior. Therefore moisture absorption is expected to improve with this kind of process when compared with specimens that are made by hand lay-up technique. Surprisingly, it was observed that the transverse flexural modulus increases, hinting at a low fiber transverse modulus. Although good fiber matrix impregnation was observed the resin did not penetrate inside the lumen with the hand lay-up technique. The transverse and longitudinal properties of composites made by hand lay-up are also studied.