Abstract

Hemicellulose acetates were prepared under homogeneous reaction conditions in the system N, N-dimethylacetamide/lithium chloride by reacting the native hemicelluloses with acetic anhydride in the presence of 4-dimethylaminopyridine within 72 h at 60–85°C. The products obtained were characterised by means of Fourier transform infrared chromatography, gel permeation chromatography, and thermal analysis. The degree of substitution of acetylated hemicelluloses ranged between 0.74 and 1.49 as a function of experimental conditions. Under an optimum reaction condition (85°C, 60 h), over 80% hydroxyl groups in native hemicelluloses were acetylated. The molecular weight measurements showed that a significant degradation and hydrolysis of the products appeared at only a prolonging period of 72 h. It was found that the thermal stability of the products increased by esterification.

Full Text
Paper version not known

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.