Lignin-containing coatings for packaging materials

• The mechanical properties and chemical stability in water of self-supporting films made from aqueous solutions of starch and lignin, and the barrier properties of paperboard coated with solutions of these polymers have been studied. The dissolution of starch from the starch-lignin films in contact with the model liquids was decreased significantly when lignin was added to the starch films. The addition of ammonium zirconium carbonate (AZC) to the formulations as a crosslinking agent substantially increased the storage modulus of the starch-lignin films, which indicated that crosslinking had occurred. The addition of AZC to the formulations also led to a decrease in dissolution of both starch and lignin from the starch-lignin films in contact with model liquids. The effect of AZC on the water stability of the films was greater when the pH of the starch-lignin-AZC solution was adjusted with ammonia rather than NaOH. The addition of NH4Cl solution as a presumed catalyst to the recipe when the pH adjustment was performed with NaOH did not improve the effect of AZC on the water stability of the films. The water vapour transmission rate of the coated paperboard decreased slightly when AZC was added to the coating formulation.

Ämnesord

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

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

Nyckelord

barrier coatings

glycerol

lignin

mechanical properties

starch

Ammonia

Chemical stability

Chlorine compounds

Coatings

Crosslinking

Dissolution

Packaging materials

Paperboards

pH effects

Sodium hydroxide

Solutions

Zirconium compounds

Barrier properties

Coated paperboard

Coating formulations

Cross linking agents

Self-supporting film

Transmission rates

Water stability

Chemical Engineering

Publikations- och innehållstyp

ref (ämneskategori)

art (ämneskategori)