packaging (Arvanitoyannis & Bosnea, 2001), the large
amount of solid wastes created has presented a pressing
environmental issue.
Weak barrier properties to water vapor and gases are
other critical issues in food packaging. For example, fresh
products that are alive (e.g., vegetables, fruits, meats)
need to be packaged in O2 permeable materials with an
optimal transmission rate, whereas processed products do
not require such mass transfer. Matching of barrier performance
with specific products to extend their shelf-life with
the limited commodity thermoplastics available is challenging.
Although polymer blends and multilayered composite
structures have been developed to expand the
functional properties of thermoplastics, problems remain
unresolved such as high cost and difficulty in recycling
these materials.