Interfacial activity and emulsion stabilization of dissolved cellulose

• Some aspects of the interfacial behavior of cellulose dissolved in an aqueous solvent were investigated. Cellulose was found to significantly decrease the interfacial tension (IFT) between paraffin oil and 85 wt% phosphoric acid aqueous solutions. This decrease was similar in magnitude to that displayed by non-ionic cellulose derivatives. Cellulose's interfacial activity indicated a significant amphiphilic character and that the interfacial activity of cellulose derivatives is not only related to the derivatization but inherent in the cellulose backbone. This finding suggests that cellulose would have the ability of stabilizing dispersions, like oil-in-water emulsions in a similar way as a large number of cellulose derivatives. In its molecularly dissolved state, cellulose proved to be able to stabilize emulsions of paraffin in the polar solvent on a short-term. However, long-term stability against drop-coalescence was possible to achieve by a slight change in the amphiphilicity of cellulose, effected by a slight increase in pH. These emulsions exhibited excellent stability against coalescence/oiling-off over a period of one year. Ageing of the cellulose solution before emulsification (resulting in molecular weight reduction) was found to favour the creation of smaller droplets.

Ämnesord

TEKNIK OCH TEKNOLOGIER  -- Kemiteknik (hsv//swe)

ENGINEERING AND TECHNOLOGY  -- Chemical Engineering (hsv//eng)

Nyckelord

Adsorption

Amphiphilicity

Cellulose molecules

Emulsions

Interfacial activity

Oil-water interface

Cellulose derivatives

Coalescence

Dissolution

Emulsification

Ostwald ripening

Paraffin oils

Paraffins

Emulsion stabilization

Interfacial behaviors

Molecular weight reductions

Oil water interfaces

Oil-in-water emulsions

Cellulose

Agglomeration

Dissolving

Publikations- och innehållstyp

ref (ämneskategori)

art (ämneskategori)