Eastman Cellulose Esters are versatile bio-based polymers used to improve properties within various paint, coating, ink, adhesive, and membrane fabrication applications. These cellulose esters are characterized by three main types of organic acid esters of cellulose: cellulose acetate (CA), cellulose acetate butyrate (CAB), and cellulose acetate propionate (CAP) polymers. In general, all cellulose ester grades may be used in formulations as a film-forming resin, coresin, or additive and provide improved properties such as better flow and leveling, antiblocking, faster solvent release, and resistance to weathering, yellowing, and chemical attack.
Eastman Cellulose Acetate Butyrate polymers are the most flexible in terms of the properties they can improve in a coating, ink, or adhesive application. Cellulose acetate butyrate ranges in molecular weight and level of butyryl and hydroxyl substitution on the polymer backbone. Grades with higher butyryl levels provide better flexibility to films, greater compatibility with resins, and broader solubility in a variety of organic solvents. Higher hydroxyl levels allow for better solubility in alcohols and facilitate higher cross-linking density in thermoset systems. Grades of cellulose acetate butyrate with lower molecular weight provide lower viscosity to solutions and can offer benefits in VOC reduction through lower solvent demand.
Eastman Cellulose Acetate polymers are widely used as a raw material in manufacturing plastics and filtration membranes. Cellulose monoacetate, diacetate, and triacetate grades are available based on the varying degree of substitution of the cellulose acetate polymer. These options allow customization over the physical properties necessary to create materials of desired specifications. In coating applications, cellulose acetate has limited compatibility with most resins and is only soluble in strong solvents such as acetone, methyl ethyl ketone, and ethyl acetate. However, it provides excellent hardness and resistance to solvents and grease, making it ideal for tough, abrasion-resistant topcoat applications for outdoor signs and decals, barrier coatings for paper, and protective coatings for plastics.
Eastman Cellulose Acetate Propionate polymers can be viewed as intermediate options between cellulose acetate butyrate and cellulose acetate. They form slightly harder films than Eastman Cellulose Acetate Butyrate polymers and do not provide as many options for molecular weight and substitution level. Cellulose acetate propionate contributes similar functionality and benefits as cellulose acetate butyrate but is virtually odorless. Due to this, cellulose acetate propionate is most ideal for packaging ink and overprint varnish applications.
Click the link below to view additional content, data, and literature on cellulose esters. For more information on Eastman Cellulose Ester grades, scroll down to view the various options available.
Eastman™ Cellulose Ester Brochure