Dynamic mechanical behaviour of resorcinol-formaldehyde matrix and its composites reinforced with natural fibers of Luffa cylindrica (LC) has been studied. The effects of fiber loading, alkali treatment on fiber, temp...Dynamic mechanical behaviour of resorcinol-formaldehyde matrix and its composites reinforced with natural fibers of Luffa cylindrica (LC) has been studied. The effects of fiber loading, alkali treatment on fiber, temperature and frequency on storage modulus and mechanical-loss factor of the composites were studied. The dynamic mechanical behaviour of the composites and pure matrix has been investigated in the frequency range from 0.1 Hz to 10 Hz and temperature range from 26℃ to 100℃. The experimental results show that the values of storage modulus of the composites increase with increase in fiber loading. The storage modulus of treated LC fiber composites were found to be enhanced when compared with the untreated fiber composites. It was also found that mechanical-loss factor was more when untreated LC fibers were incorporated in the composites and decreased with the incorporation of treated LC fiber. The storage modulus of all the composites increased with frequency but decreased with rise of temperature. The glass transition temperature of the composites was evaluated from the peaks of tan delta variations.展开更多
In view of biomedical applications of cellulose fibers in orthopedics, dentistry and reconstructive surgery, Luffa cylindrica (LC), a local forest product of Orissa, India, has been used for preparation of alkali trea...In view of biomedical applications of cellulose fibers in orthopedics, dentistry and reconstructive surgery, Luffa cylindrica (LC), a local forest product of Orissa, India, has been used for preparation of alkali treated LC fiber modified with calcium carbonate and calcium phosphate separately by following standard procedures. FTIR and Raman spectra were obtained for these samples at wavelength range 500 - 4000 cm–1 and 300 - 3000 cm–1 respectively. Lattice structures of cellulose i.e., crystalline cellulose and amorphous cellulose were detected using Raman spectroscopy and discussed. The property of cellulose such as its degree of crystallinity was determined from intensity of FT IR peaks and was found to be 74.12%. The presence of calcite and hydroxy apatite, polymorphs of calcium carbonate and calcium phosphate respectively were confirmed in the treated modified LC fibers which can be used as bioactive materials.展开更多
文摘Dynamic mechanical behaviour of resorcinol-formaldehyde matrix and its composites reinforced with natural fibers of Luffa cylindrica (LC) has been studied. The effects of fiber loading, alkali treatment on fiber, temperature and frequency on storage modulus and mechanical-loss factor of the composites were studied. The dynamic mechanical behaviour of the composites and pure matrix has been investigated in the frequency range from 0.1 Hz to 10 Hz and temperature range from 26℃ to 100℃. The experimental results show that the values of storage modulus of the composites increase with increase in fiber loading. The storage modulus of treated LC fiber composites were found to be enhanced when compared with the untreated fiber composites. It was also found that mechanical-loss factor was more when untreated LC fibers were incorporated in the composites and decreased with the incorporation of treated LC fiber. The storage modulus of all the composites increased with frequency but decreased with rise of temperature. The glass transition temperature of the composites was evaluated from the peaks of tan delta variations.
文摘In view of biomedical applications of cellulose fibers in orthopedics, dentistry and reconstructive surgery, Luffa cylindrica (LC), a local forest product of Orissa, India, has been used for preparation of alkali treated LC fiber modified with calcium carbonate and calcium phosphate separately by following standard procedures. FTIR and Raman spectra were obtained for these samples at wavelength range 500 - 4000 cm–1 and 300 - 3000 cm–1 respectively. Lattice structures of cellulose i.e., crystalline cellulose and amorphous cellulose were detected using Raman spectroscopy and discussed. The property of cellulose such as its degree of crystallinity was determined from intensity of FT IR peaks and was found to be 74.12%. The presence of calcite and hydroxy apatite, polymorphs of calcium carbonate and calcium phosphate respectively were confirmed in the treated modified LC fibers which can be used as bioactive materials.
