Present investigation is aimed on chemically modified of Sunn Hemp (Crotalaria juncea) fiber for composite fabrication. An increment in cellulose crystallinity with crystallite size is observed from X-ray diffraction study. The signature of impurities removal and an uneven surface are confirmed from Fourier Transmission Infrared Spectroscopy and Field Emission Scanning Electron Microscopy. Afterwards, both raw sunn hemp-reinforced fiber composite and dewaxed sunn hemp fiber-reinforced composite were fabricated using hand lay out method and the mechanical as well as dielectric properties of composite are studied. A better mechanical strength is found in DSHC which may attribute to rough surface and increased cellulose crystallinity through dewaxing process that promoted a fine interfacial bonding between fiber and matrix. Dielectric constants and losses are found to be less in dewaxed sunn hemp fiber-reinforced composite in comparison to raw sunn hemp-reinforced fiber composite due to decrease of water polar groups, which lead to lessening the effect of space charge polarization by treatment. Complex impedance and modulus study revealed the presence of single relaxation process in both systems. Lower ac conductivity value is observed in dewaxed sunn hemp fiber-reinforced composite due to decreasing of conducting polar OH groups. As a whole, the effort is established to correlate the mechanical and dielectric properties with fine structural parameters of the fiber.
The low density, lightweight, easy processing and biodegradability nature of Natural fiber-reinforced polymer composite have gained enough attention from many researchers and scientists. Kapok Fiber (Ceiba pentandra) is a natural cellulosic fiber have a hollow microtubular structure and a high degree of hollowness. The hand lay-up technique has been adopted for kapok fiber-reinforced epoxy polymer composite fabrication with different fiber loading(2, 3, 4, 5, 6 and 7 wt %). The mechanical strength of kapok fiber-reinforced polymer epoxy composite is investigated through the flexural and tensile test. The best flexural and tensile performance is observed at 5 wt% loading of kapok fiber. To increase compatibility between fiber and epoxy matrix dewaxing process is adopted. The effect of dewaxing on cellulose crystallinity, crystallinity size, surface morphology, elemental composition and functional groups of fiber are studied. The roughness of the fiber surface increases after dewaxing due to the partial removal of non-cellulosic compounds like lignin, pectin, wax and some oily substances. The increase in fiber surface roughness and cellulose crystallinity index by chemical treatment made a strong interlocking at the fiber-matrix interface. The effect of dewaxing on mechanical strength is also studied to fabricate the composite for the benefit of society.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.