Evaluation of esterification routes for long chain cellulose esters
Pia Willberg-Keyriläinen1, Jarmo Ropponen1
1VTT Technical Research Centre of Finland Ltd, Tietotie 4E, P.O Box 1000, FI-02044, VTT, Finland.
Heliyon
|December 5, 2019
Summary
Long chain cellulose esters offer sustainable material potential. Acyl chloride esterification yielded the highest degree of substitution (DS), with ozone pretreatment further enhancing DS and reaction efficiency.
Area of Science:
- Polymer Science
- Materials Science
- Green Chemistry
Background:
- Long chain cellulose esters are bio-based, internally plasticized materials with significant potential in coatings, films, and plastics.
- Developing efficient synthesis methods for these esters is crucial for their wider application.
Purpose of the Study:
- To synthesize long chain cellulose esters with varying side chain lengths using different esterification methods.
- To evaluate the effectiveness of various esterification techniques and the impact of cellulose pretreatment on the degree of substitution (DS) and reaction efficiency.
Main Methods:
- Homogeneous esterification using acyl chloride, CDI activation, vinyl transesterification, and anhydride routes.
- Heterogeneous esterification using the acyl chloride method.
- Cellulose pretreatment using ozone to modify molar mass.
Main Results:
- Acyl chloride method in homogeneous esterification was most effective, yielding DS values from 0.3 to 1.3, dependent on side chain length.
- CDI activation, vinyl transesterification, and anhydride routes resulted in lower DS values.
- Ozone pretreatment of cellulose decreased molar mass but increased DS and reaction efficiency of synthesized esters.
- Acyl chloride method was the only effective method for heterogeneous esterification.
Conclusions:
- Acyl chloride method is superior for synthesizing long chain cellulose esters with high DS, particularly in homogeneous systems.
- Ozone pretreatment is a viable strategy to enhance the synthesis efficiency and DS of cellulose esters.
- Further research into optimizing these methods can unlock the full potential of cellulose esters in various industrial applications.
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