Gas barrier properties are the Achilles heel when it comes to using biopolymers in (fresh) food packaging. Around the world, scientists and industry are working – often together – to develop feasible alternatives based on renewable resources to replace the use of conventional petroleum-based plastics. Solutions up to now have mainly involved the use of ‘hybrid’ laminates; at the same time technologies such as atomic layer deposition, in which Al2O3 coatings with thicknesses of 10-50 nm are “grown” on bioplastic materials, are being explored to discover whether these produce suitable barriers for use in food packaging, without affecting the biodegradability.
By comparison, the use of wood to improve permeability against, for example, oxygen, sounds relatively low-tech; old school, even.
Source: plastics, 2012-02-06.