In the recent years awareness has been raised due to environmental and economic concerns posed by the huge oil based products stream that flood the market. Along with the growing plastic production and consumption, the petroleum based economy has been stumbling the last years with high oil prices and scarcity (Figure 1).
Petrochemical-based plastics have been increasingly used in packaging for a few decades because their large availability at relatively low monetary cost and their good mechanical performance. However, nowadays their use has to be restricted or controlled in a better way given the serious ecological problems they pose for recyclability and biodegradability (2).
Packaging has been a major focus of attention in the environmental debate more than most manufactured products due to its high visibility within the waste-stream, Over one-third of the average household’s rubbish (3) and municipal solid waste arise from packaging (4). It is found almost everywhere, most commonly in the food industry where it represents 60% of all packaging (5).
One of the many issues that plastics displays is at their disposal stage; ending mass filling up landfills as non biodegradable materials, or very often contaminated by remaining food or other substances at recycling facilities making the recycling process impracticable and usually, economically not convenient. Even though materials can be recycled or recovered end up being disposed of in regulated landfills or incinerated due to the hindering by the lack of facilities and technology necessary to separate materials to avoid contamination (6).
A growth interest has been shown into developing green materials made from naturally occurring renewable resources due to its recyclability and biodegradability as a possible solution to the problems that oil based materials represent. One of the largest consumer products producer Procter & Gamble announced in 2010 a initiative to reduce its packaging use towards a sustainable agenda; using recyclable or renewable produced materials with a final goal of eliminate all fosil-fuel-based virgin plastics use (7).
Studies conducted with polylactic acid (PLA) and Starch based blends, present these materials as a good option as commodity resin for general packaging applications since they satisfy many favourable requirements as thermoplastics (8), (9), (10), (11).
Despite the promising properties presented by these materials, there are still a few problems to overcome such as stiffness, brittleness and low thermo-mechanical properties that limit the use of PLA in the packaging field. Additives (i.e. plasticizers) or fillers (i.e. fibers) can be added during its processing to help enhance the PLA performance. One possible solution is the use of plasticizers able to reduce the glass transition temperature (Tg), inducing somehow an improvement of the elongation at break and/or impact resistance and the use of natural fibres to improve its...