Abstract
The total degree of substitution, DS(≡‹‹F››), the distribution of DS and the distribution of the substituent group in a glucopyranose unit ‹‹fk›› (the suffix k means the carbon position in the C1 chain conformation) are accurately defined for cellulose derivatives. ‹‹fk›› of cellulose acetate (CA) was evaluated from the 1H nuclear magnetic resonance (NMR) chemical shift of the O-acetyl protons and the 13C NMR chemical shift of the O-acetyl carbons. 1H NMR method is applicable only to completely substituted cellulose acetate, but the 13C NMR method is proved applicable for the entire range of the DS (0—3). CA (DS=2.92)–trichloromethane, CA (DS=2.46)–acetone, and CA (DS=0.49)–dimethyl sulfoxide systems are employed successfully. ‹‹F›› values determined by 13C NMR spectrum are in good agreement with those by the chemical analysis. The reactivity of the O-acetyl groups during the hydrolysis reaction process using hydrochloric acid as a catalyst decreases in the following order: C2>C6>C3.
Sign-in/Register to access full text options 
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 callDisclaimer: 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.
