A barrier composition which is injection mouldable and able to be made into a transparent film or incorporated (by co-
extrusion and / or lamination) into multi-layer film products, the composition on
dry basis: a) from 45 to 90% by weight of a
starch and / or a
modified starch selected from starches modified by reaction with a hydroxyl
alkyl group, an acetate or a
dicarboxylic acid anhydride or a
grafting polymer; b) from 4 to 12% by weight of a
water soluble polymer selected from
polyvinyl alcohol, polyvinylacetate, and copolymers of
ethylene and vinylalcohol which have a
melting point compatible with the
molten state of the
starch components c) from 5 to 45% by weight of a non-crystallising mixture of
sorbitol and at least one other
plasticizer selected from
glycerol,
maltitol,
xylitol,
mannitol,
glycerol trioleate, epoxidised linseed or
soybean oil,
tributyl citrate, acetyl tri-ethyl citrate,
glyceryl triacetate, 2,2,4-trimethyl-1,3-pentanediol diisobutyrate;
polyethylene oxide or
polyethylene glycol; d) from 0.3 to 2.5 % by weight of a C12-22
fatty acid or salt; e) from 0.25% to 3% of an emulsifier
system having a
hydrophilic lipophilic balance value between 2 and 10. The barrier film may be co-injection moulded with
polyethylene terephthalate (PET) or
polylactic acid (PLA) for blow moulding into beverage bottles, with polyethylene (PE) or
polypropylene (PP) or biodegradable polymers for high gas-barrier containers or closures, or may be co-extruded with polyethylene,
polypropylene or
polylactic acid for thin film packaging applications or for blow-moulded containers.