Chemistry of ETHOCEL Ethylcellulose

ETHOCEL* ethylcellulose is derived from cellulose. Like cellulose, the backbone of the molecule of ETHOCEL is based on repeating anhydroglucose units. The basic structure is shown here:

Structure of ETHOCEL Ethylcellulose

Specific properties of the various ETHOCEL polymers are determined by the number of anhydroglucose units in the polymer chain and the degree of ethoxyl substitution.

ETHOCEL polymers are white to light tan granular powders with a bulk density of approximately 0.4 g/cc. These polymers are packaged in fifty-pound bags.

Seven different ETHOCEL Premium ethylcellulose products are available for pharmaceutical applications, as shown in Table below. ETHOCEL Standard 7, 10, and 100 Premium are also available in a fine particle size designated ETHOCEL Std 7 FP, Std 10 FP, and Std 100 FP Premium. These products were designed specifically for pharmaceutical formulations when the ETHOCEL is used in an unsolubilized form such as in direct compression controlled release tablets, granulation and/or agglomeration. In these applications, the particle size distribution influences the release rate and tablet compressibility.

ETHOCEL Premium Polymers for Pharmaceutical Applications

Product Viscosity Designation	Solution Viscosity¹ Range, cP	Ethoxyl Content, %
ETHOCEL Standard 4 Premium	3–5.5	48.0–49.5
ETHOCEL Standard 7 Premium²	6–8	48.0–49.5
ETHOCEL Standard 10 Premium²	9–11	48.0–49.5
ETHOCEL Standard 14 Premium	12.6–15.4	48.0–49.5
ETHOCEL Standard 20 Premium	18–22	48.0–49.5
ETHOCEL Standard 45 Premium	41–49	48.0–49.5
ETHOCEL Standard 100 Premium²	90-110	48.0–49.5

¹Note: Viscosities are for 5% solutions measured at 25°C in an Ubbelohde viscometer.
The solvent is 80% toluene and 20% alcohol.

²ETHOCEL Standard 7,10, and 100 Premium are also offered as a fine particle; designation ETHOCEL Standard 7 FP Premium, ETHOCEL Standard 10 FP Premium, and ETHOCEL Standard 100 FP Premium.

®™*Trademark of The Dow Chemical Company ("Dow") or an affiliated company of Dow.