Study of mechanical and machining behavior on silane treated kenaf fibre and nano silica reinforced epoxy resin hybrid composite

Abstract

Nano-silica toughened epoxy resin reinforced with silane surface-modified kenaf fibre has been fabricated for typical engineering applications. This current work aims to reveal the importance of surface covering agent (silane) on kenaf fibre and nano-silica particles in mechanical, fracture toughness, low velocity drop load impact and drilling characteristics of hybrid epoxy composites fabricated. A bis-phenol based epoxy resin was used as matrix, while the cellulose removed kenaf continuous woven mat (450 GSM) was used as primary reinforcement. Moreover there was a secondary reinforcement to alter the properties of base matrix at molecular level. Silica particles of 20 nm were used as secondary reinforcement for this present study. The fibre and particles were surface treated using 3-Aminopropyltriethoxysilane was used as surface modifier. The silane surface treatment process was done at aqueous solution with acetone as promoter. These composites were fabricated using hand layup method and subsequently cured at room temperature for 24 hr and post cured for 48 hr. The test specimens based on ASTM standards were cut from the prepared epoxy hybrid composite by using an abrasive water jet machine with recommended parameters. A ultimate tensile stress and tensile modulus of 172 MPa and 6776 MPa were noted for surface-modified composite designation EKS3. Similarly in flexural strength also the composite designation EKS3 in surfacemodified condition gives better results on comparing with other composites. The highest Izod cantilever beam impact toughness of 6.45 J was recorded for silane surface-grafted hybrid composite designation EKS3. The calculated inert-laminar shear strength shows highest value for surface-modified EKS composite designation. The water uptake behavior of epoxy resin composites shows highest water absorption resistance for surface-treated nano-silica dispersed epoxy composite. The composite designation of surface-modified EKS3 gives maximum closest contact angle of 63o with pure epoxy resin. newline