Naturally occurring cellulose consists of a repeating structure of anhydroglucose units that each contain three reactive hydroxyl sites. In the production of ethylcellulose these reactive hydroxyl sites are converted into ethyl ether groups to produce a cellulose derived polymer with added hydrophobicity that are useful in many industrial applications.
Ethylcellulose in Specialty Coatings
Ethylcellulose polymers provide a unique combination of properties that are particularly useful in a variety of specialty coating applications to improve durability and efficiency . Some common specialty coating applications where ethylcellulose is particularly useful are listed below.
Heat Seal Coatings
Ethylcellulose is soluble in most hot polymers, solvents, and oil & wax mixtures used in hot melt formulations and is also highly thermoplastic. When added to heat seal coatings ethylcellulose provides an increase in green bond strength that is especially useful in applications where stresses are applied to a freshly sealed joint.
Ethylcellulose is often used in thin film coatings for paper due to it's combination of flexibility and toughness. Paper coatings formulated with ethyl cellulose also provide good gloss, block resistance, and excellent water vapor transmission resistance.
Ethylcellulose is works incredibly well as a rheology modifier and temporary binder for glass coatings. When used in glass coatings ethyl cellulose helps to improve initial bond strength and is subsequently removed by heating. Ethylcellulose burns out cleanly upon heating leaving behind no residue to interfere with long term adhesion to glass.
ETHOCEL™ ethylcellulose polymers are manufactured to the highest quality standards and provide best in class purity and batch to batch consistency of any commercially available ethylcellulose. A range of ETHOCEL™ grades are available for use in specialty coating applications to improve the overall durability of the coating formulation.
The viscosity and film properties of ETHOCEL™ solutions is highly dependent on the solvents used in the system. For instance, solutions of ETHOCEL in aromatic hydrocarbons are highly viscous whereas solutions of ETHOCEL™ in methanol or ethanol have a much lower viscosity at the same solids concentration. In this example it is also important to note that films formed with ETHOCEL™ in primary alcohols are very brittle and not typically commercially useful. Viscosity and film properties of ETHOCEL™ Std. 10 in common solvents are listed below for comparison.
Viscosity & Film Properties of ETHOCEL™ in Various Solvents
Butyl Acetate, 90%
Ethanol, Formula 30
Ethyl Acetate, 99%
Methyl Ethyl Ketone
In many formulations the most practical solvents for ETHOCEL™ are mixtures that provide the lowest viscosity consistent with good film properties and that have a suitable evaporation rate. ETHOCEL™ is also highly compatible with other components in coating formulations including pigments, dyes, antioxidants, and most modifying polymers.
If you have specific formulation questions ChemPoint is here to help. Contact us today to connect with a coating industry expert to discuss your next specialty coating formulation.