کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
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1384790 | 982418 | 2008 | 9 صفحه PDF | دانلود رایگان |

Esterification of wheat straw hemicelluloses with acetyl chloride, propionyl chloride, n-octanoyl chloride, lauroyl chloride, palmitoyl chloride, stearoyl chloride, and oleoyl chloride, respectively, using N-bromosuccinimide (NBS) as a catalyst was achieved in DMF/LICl medium by microwave irradiation. The effects of various acyl chlorides and the molar ratios of xylose units in hemicelluloses/acyl chloride on the degree of substitution (DS) were investigated and DS reached up to 1.34 by a few minutes. 13C NMR studies showed that the esterification occurred preferentially at the C-3 and C-2 positions. On the other hand, microwave irradiation brought a partial degradation of the polymer, and therefore resulted in a slight decrease in thermal stability of the hemicellulosic derivatives in comparison with conventional heating technique.
Journal: Carbohydrate Polymers - Volume 73, Issue 4, 5 September 2008, Pages 612–620