Effects of salts, solvents, and substituents on the reaction of cellulose with epoxy compounds

Abstract

Effects of salts, solvents, and substituents on the reaction of cellulose with epoxy compounds were re-investigated and compared with the published data. The salt effect could be described mainly by the electronegativity or the acidity. of the cations, and also by the nucleophilicity or the basicity of the anions. The variation of the reaction with solvents for epoxy compounds could be explained by the solubility parameter of the solvents. The substituent effect of the epoxy compounds on this addition reaction was elucidated by the modified Taft's equation, (log klog ko)/a* = (e, + psEs)/a*. The mechanism for the reaction was discussed in the light of the reinvestigated phenomena. ZUSAMMENFASSUNG:Salzeffekte sowie Losungsmittel-und Substituenteneffekte bei der Reaktion von Cellulose mit Epoxyverbindungen wurden untersucht und rnit Literaturangaben verglichen. Der Salzeffekt konnte hauptsachlich mit der Elektronegativitat oder der Aciditat des Kations sowie mit der Nucleophilie oder der Basizitat des Anions beschrieben werden. Die Variation der Reaktion rnit den Losungsmitteln der Epoxyverbindungen konnte auf deren Loslichkeitsparameter zuruckgefuhrt werden. Der Substituenteneffekt der Epoxyverbindungen bei dieser Additionsreaktion wurde rnit Hilfe der modifizierten Gleichung von Taft, (logk-logk,)/a* =(p, -p,ES)/a*, ermittelt. Unter dem Gesichtspunkt der neuen Ergebnisse wurde der Reaktionsmechanismus diskutiert.

Biomacromolecules and Bio‐Related Macromolecules

“…The reaction was re-investigated Scheme 9. quantitatively with respect to reaction mode and mechanism by varying the reaction conditions (salts, solvent, substituents of oxiranes). [40] Cellulose was used as a drug carrier for a-chymotrypsin, where the enzyme was immobilized on periodate-oxidized cellulose. [41] The properties and release of the enzyme from the polymer was studied.…”

“…Reaction of cellulose with epoxy compounds has a long history since 1921. The reaction was re‐investigated quantitatively with respect to reaction mode and mechanism by varying the reaction conditions (salts, solvent, substituents of oxiranes) 40…”