Comparative Study of Acetylation of Rice Straw Fiber With or Without Catalysts


  • Xiao Feng Sun
  • RunCang Sun


Rice straw fiber, acetylation, catalyst, FT-IR, <sup>13</sup>C-NMR, thermal stability


The reaction of acetic anhydride with rice straw fiber without solvent was investigated, and the extent of acetylation was measured by weight percent gain, which increased with an increment of reaction time or temperature. Meanwhile, the potential of four tertiary amine catalysts (pyridine, 4-dimethylamino pyridine, N-methyl pyrrolidine, and N-methyl pyrrolidinone) for the acetylation at 100°C for 0.5 h was also studied. The hypernucleophile 4-dimethylamino pyridine was found to be the most effective catalyst of those studied. The characterization of acetylated fibers was performed by FT-IR, CP MAS 13C-NMR, and thermal studies. Thermal stability of acetylated rice straw fiber was found to be higher than the unreacted fiber and increased with weight percent gain due to the acetylation.


Beall, F. C. 1969. Thermogravimetric analysis of wood lignin and hemicelluloses. Wood Fiber 1:215-226.nBolton, J. 1995. The potential of plant fibers as crops for industrial use. Outlook Agric. 24:85-89.nBoonstra, M. G., A. Pizzi, P. Tekely, and J. Pendlebury. 1996. Chemical modification of Norway spruce and Scots pine. A 13C NMR CP-MAS study of the reactivity and reactions of polymeric wood components with acetic anhydride. Holzforschung 50:215-220.nBueso, J. G., M. Westin, R. Torgilsson, P. O. Olesen, and R. Simonson. 1999. Composites made from acet-ylated lignocellulosic fibers of different origin. Part 1. Properties of dry-formed fiberboards. Holz Roh-Werk-stoff 57:433-438.nCallow, H. J. 1951. Acetylation of cellulose and lignin in jute. J. Indian Chem. Soc. 28:650-610.nConnors, K. A., and K. S. Albert. 1973. Determination of hydroxyl compounds by 4-dimelhylaminopyridine-catalyzed acetylation. J. Pharmaceutical Sci. 62:845-846.nErwin, L. H. 1997. Strawboard, biocomposites, and fields of dreams. Evergreen Newsletter for New Uses Council, April.nGoldstein, I. S. 1960. Improving fungus resistance and dimensional stability of wood by treatment with â-propiolactone. U.S. patent 2 931 741.nGupta, S., R. N. Madan, and M. C. Bansal. 1987. Chemical composition of Pinus caribaea hemicellulose. Tappi J. 70:113-114.nHill, C. A. S., and J. Hillier. 1999. Studies of the reaction of carboxylic anhydrides with wood. Experimental determination and modelling of kinetic profiles. Phys. Chem. Chem. Phys. 1:1569-1576.nHill, C. A. S., H. P. S. A. Khalil, and M. D. Hale. 1998a. A study of the potential of acetylation to improve the properties of plant fibers. Ind. Crops Prod. 8:53-63.nHill, C. A. S., D. Jones, G. Strickland, and N. S. Cetin. 1998b. Kinetic and mechanistic aspects of the acetylation of wood with acetic anhydride. Holzforschung 52: 623-629.nHill, C. A. S., N. S. Cetin, and N. Ozmen. 2000. Potential catalysts for the acetylation of wood. Holzforschung 54: 269-272.nHofle, G., W. Steglich, and H. Vorbruggen. 1978. 4-Dialkylaminopyridines as highly active acylation catalyst. Angew. Chem. Int. Ed. Engl. 17:569-583.nKarr. G. S., and X. S. Sun. 2000. Strawboard from vapour phase acetylation of wheat straw. Ind. Crops Prod. 11:31-41.nLove, G. D., C. E. Snape, and M. C. Jatvis. 1998. Comparison of leaf and stem cell wall components in barley straw solid state 13C NMR. Phytochemistry 49:1191-1194.nMalm. C. J., L. J. Tanghe, B. C. Laird, and G. D. Smith. 1953. Relative rates of acetylation of the hydroxyl groups in cellulose acetate. J. Amer. Chem. Soc. 75:80-84.nPizzi, A., A. Stephanou, M. J. Boonstra, and A. J. Pendlebury. 1994. A new concept on the chemical modification of wood by organic anhydrides. Holzforschung 48:91-94.nRana, A. K., R. K. Basak, B. C. Mitra, M. Lawther, and A. N. Bankrjee. 1997. Studies of acetylation of Jute using simplified procedure and its characterization. J. Appl. Polym. Sci. 64:1517-1523.nRowell, R. M. 1982. Distribution of reacted chemicals in southern pine modified with acetic anhydride. Wood Sci. 15:172-182.nRowell, R. M. 1983. Chemical modification of wood. Forest Prod. Abstr. 6:363-382.nRowell, R. M. 1992. Opportunities for lignocellulosic materials and composites. ACS Symposium series 476, ACS, Washington, DC, Pp. 12-27.nRowell, R. M., A. M. Tillman, and R. Simonson. 1986. A simplified procedure for the acetylation of hardwood and softwood flakes for flakeboard production. J. Wood Chem. Technol. 6:427-448.nRowell, R. M., R. Simonson, and A. M. Tillman. 1990. Acetyl balance for the acetylation of wood particles by a simplified procedure. Holzforschung 44:263-269.nRowell, R. M., R. Simonson, S. Hess, D. V. Plackett, D. Cronshaw, and E. Dunningham. 1994. Acetylation distribution in acetylated whole wood and reactivity of isolated wood cell wall components to acetic anhydride. Wood Fiber Sci. 26:11-18.nSaikia, C. N., F. Ali, T. Goswami, and A. C. Ghosh. 1995. Esterification of high α-cellulose extracted from Hibiscus cannabinus L. Ind. Crops Prod. 4:233-239.nSatchell, D. P. N. 1963. An outline of acylation. Quart. Rev. 17:160-203.nSen, M. K., and M. Ramaswamy. 1957. Kinetics of fibrous acetylation of cotton and jute. J. Textile Inst. 48: T75-T80.nStamm, A. J., and R. H. Baechler. 1960. Decay resistance and dimensional stability of five modified woods. Forest Prod. J. 10:22-26.nSun, R. C., J. Tomkinson, F. C. Mao, and X. F. Sun. 2000. Physicochemical characterization of lignins from rice straw by hydrogen peroxide treatment. J. Appl. Polym. Sci. 79:719-932.nTarkow, H., A. J. Stamm, and E. C. O. Erickson. 1950. Acetylated wood. Report No. 1593, USDA Forest Serv. Forest Prod. Lab.n






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