Petroleum-based commodity thermoplastic

Table 10.1 Comparison of PLA properties with petroleum-based commodity thermoplastics. Adapted from [41] with permission from John Wiley and sons.

Polylactic acid or polylactide (PLA) is a thermoplastic aliphatic polyester that can be derived from renewable resources, such as corn starch or sugarcanes. Although PLA has been known for more than a century, it has become of great commercial interest in recent years because of its renewability and degradability to natural metabolites. In addition, the properties of PLA can be varied over a wide range which makes it suitable to be used as a substitute to many petroleum based commodity plastics, such as polyolefins,... 

Polylactide (PLA) and thermoplastic starch-(TPS) are two of the most promising biobased materials currently available on the market. The expected rise in the cost of petroleum-based commodities in the next decades opens bright perspective for these materials. Their biodegradability and compostability is also seen as an asset in applications that are difficult to recycle. 

Based upon their mechanical and processing properties, many natural and renewable polymers are quite suitable to replace petroleum- based plastics in specific applications where an extended life span of plastic product is not desirable. Furthermore, consumers acceptance of such bio-based plastics is expected even if natural polymer price represents a limitation on the cost of the final products. Materials such as commodity crops, agricultural waste and/or by-products are a good source of natural and renewable polymers and are comparatively less expensive. Agro-fibers, which represents a considerable portion of such natural materials is available on a worldwide basis and are being used in a variety of tq>plications. In some applications, fibrous materials have been blended with thermoplastic mauix to develop composites containing various percentages of the fibers ... 

Microbial PHA first received widespread attention during the petroleum crisis of the 1970s as a potential substitute for petrochemical-based plastics. Besides being a thermoplastic with properties comparable to that of PE, PHA are also completely biodegradable. The ability to produce PHA from renewable carbon sources also ensures a sustainable green chemistry process. A considerable amount of work has been focused on the production of various types of PHA for applications as commodity plastics. Initially, PHA were used to make everyday articles such as shampoo bottles and packaging materials. 

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