Selection considerations

Eastman cellulose esters are available with a range of substituents and molecular weights that determine their solubility, compatibility, viscosity, film formation, and hardness. The size of the acyl group—acetyl, propionyl, or butyryl—on the cellulose backbone affects the packing density and the polarity of the cellulose chains. The cellulose backbone provides three hydroxyls per anhydroglucose unit, which are replaced during esterification with acyl groups. The extent of this replacement of the hydroxyl group can be expressed as degree of substitution with a range of 0 (cellulose) to 3 (tri-ester) or in weight percent of acyl and hydroxyl.

The following table provides guidance about the impact of butyryl content, hydroxyl content, or viscosity on film properties.

For a cellulose ester with greater: Choose a cellulose ester with:
CompatibilityHigher butyryl content
SolubilityHigher butyryl content or higher hydroxyl content if the solvent blend is high in alcohol
ReactivityHigher hydroxyl content
ToughnessHigher viscosity
HardnessLower butyryl content or higher hydroxyl content 
Chemical resistanceLower butyryl content
FlexibilityHigher butyryl content
Higher solids at fixed viscosityLower viscosity
Moisture resistanceLower hydroxyl content
AdhesionHigher butyryl and hydroxyl content

Want to learn more about formulating with cellulose esters for your application?

Eastman cellulose esters are compatible with many of the common resins and solvents used in the formulation of coatings and inks. To assist formulators in selecting the optimal solvent and resin combinations Eastman has also developed solvent and resin selector guides as well as sophisticated online tools.

Solvent comparison tool 

Solvent comparison toolSolvent comparison tool

Compare solvent and resin attributes and obtain a resin solubility chart for various resins.

Solvent Reformulation Tool 

Solvent reformulation toolSolvent Reformulation Tool

Assistance in optimizing the cost/performance requirements of a replacement blend or in the development of a new blend.