Acetylated wood analysis

Ohkoshi, M. and Kato, A. (1992). Distribution of substituents in acetylated wood as determined by nuclear magnetic resonance analysis. In Pacific Rim Bio-Based Composites Symposium Chemical Modification of Lignocellulosics, Plackett, D.V. and Dunningham, E.A. (Eds.). ERl Bulletin, 176, pp. 25-32. 

Ohkoshi, M. and Kato, A. (1997a). C-NMR analysis of acetyl groups in acetylated wood 1. Acetyl groups in cellulose and hemiceUulose. Mokuzai Gakkaishi, 43(4), 327-336. 

The capital cost of the batch acetylation plant was calculated at 12 million and that of the continuous process plant at 5.5 million. It was assumed that the acetylation facility would be integrated with a traditional fibreboard plant, so that fibre production and drying costs were not included in the analysis. The analysis showed that wood fibre could be acetylated to a WPG of 20 % for a cost of 562 per tonne in a batch process and 384 per tonne in a continuous process. BP subsequently lost interest in the wood acetylation process and sold the pilot plant. 

Shimizu, K., Teratini, F., Hashi, M. and Miyazaki, K. (1972). Effect of the thermal treatment on wood hemicelluloses. VI. Studies on the thermal analysis of arabinogalactan, and O-acetyl and deacetylated-galactoglucomannans. Mokuzai Gakkaishi, 18(2), 79-84. 

Aminolysis is a laborious procedure, e.g., for wood samples, a 6-7-h reaction period may be required for the aminolysis step alone. The accuracy of this method is critically dependent upon both a quantitative acetylation of phenolic hydroxyl groups and a selective deacetylation of phenolic acetyl groups. Although these requirements may not represent a serious concern in the analysis of soluble or reagent-accessible lignin preparations, they could present a problem in the case of lignocellulosic materials. 

Energy X-ray analysis of bromine in wood acetylated with tri-bromoacetyl bromide showed that bromine was distributed throughout the entire secondary wall, suggesting chemical reaction with lignin 126). Using a similar technique, the greatest percentage of chlorine in epichlorohydrin-modified wood reference was found in the S2 layer of the cell wall. This is the thickest cell wall layer and contains the most cellulose. 

All of the free hydroxyl groups are protected as acetals by reaction with methyl vinyl ether. The 0-acyl groups are then split off by treatment with alkali, and the resulting material is methylated (see Scheme 20). After hydrolysis of the methylated material, and analysis of the hy-drolyzate as alditol acetates by g.l.c.-m.s., it is possible to determine the positions and proportions of O-methyl groups and, hence, the substitution pattern of the 0-acyl groups. This procedure has been used to locate 0-acetyl groups in bacterial polysaccharides and wood polysaccharides. ... 

The reactions of NaOH with cellulose in natural fiber yielded cellulose-ONa compound and removed impurities from the fiber surface [11,12]. This is confirmed by the FTIR spectroscopic analysis as shown in Figure 14.1. The FTIR spectrum of the raw wood clearly shows the absorption band in the region of3407 cm, 2917 cm and 1736 cm due to O-H, C-H and C = O stretching vibration respectively. These absorption bands are due to hydroxyl groups in cellulose, carbonyl groups of acetyl ester in hemi-cellulose and carbonyl aldehyde in lignin. 

Hazarika A, Maji TK (2014c) Strain sensing behavior and dynamic mechanical properties of carbon nanotubes/nanoclay reinforced wood polymCT nanocomposite. Chem Eng J 247 33-41 Hazarika A, Maji TK (2014d) Thermal decomposition kinetics, flammability, and mechanical property smdy of wood polymtar nanocomposite. J Therm Anal Calorim 115 1679-1691 Hazarika A, Mandal M, Maji TK (2014) Dynamic mechanical analysis, biodegradability and thermal stability of wood polymer nanocomposites. Compos Part B 60 568-576 Hetzer M, Kee D (2008) Wootl/polymer/nanoclay composites, environmentally friendly sustainable technology a review. Chem Eng Res Des 86 1083-1093 Hill CAS, Abdirl KHPS, Hale MD (1998) A study of the potential of acetylation to improve the properties of plant fibres, frrd Crops Prod 8 53-63 Hoffmann MR, Martin ST, Choi WY, Bahnemann W (1995) Environmental application of semiconductm photocatalysis. Chem Rev 95 69-96 Huda MS, Drzal LT, Misra M, Mohanty AK (2(K)6) Wood-fiber-reinforced poly(lactic acid) composites evaluation of the physicomechanical and morphological properties. J AppI Polym Sci 102 4856-4869... 

The present article discusses the analytical information that can be obtained by MALDI-MS analysis of different types of non-acetylated and D-acetylated hemicelluloses derived from wood and pulp. Furthermore, a procedure for analyzing the molar mass parameters for hemicelluloses, utilizing size exclusion chromatography (SEC) followed by MALDI-MS analysis, is discussed. 

Figure 2. MALDFMS spectrum (positive-ion mode) of an O-acetyl-glucomannan (upper spectrum) isolated from hydrothermally treated spruce wood. Spectral analysis of the same spruce glucomannan following alkaline hydrolysis (lower spectrum).

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