Biobased plastics

Most TPEs fall in one of six categories, listed in order of increasing cost and performance styrenic block copolymers, polyolefin blends (TPOs), elastomeric alloys, thermoplastic polyurethanes (TPUs), thermoplastic copolyesters, and thermoplastic polyamides [3]. 

Styrenic TPEs are the most widely used. One such material, commercialized by BASE in 1999, is a styrene-butadiene block copolymer with a styrene content of about 70%, intended for thin film for food packaging. It has high oxygen and water permeability, and excellent toughness and optical properties. Cling films with EVA layers on the outside are also available, which provide complete recovery of deformation at elongations up to 400%, and elongation at break of over 650%. 

In recent years, interest in plastics made from renewable materials (biological sources) has increased greatly. The drive towards increasing sustainability has enabled these plastics to become more competitive with petrochemical-based plastics. Many of these materials (though not all) are also biodegradable, which is also seen as a desirable attribute. Biodegradability will be discussed further in Chapter 16. 

The language used to describe these new (or sometimes old ) materials can be confusing, and too often is misused. One particularly problematic term is bioplastics. One common definition for bioplastics is plastics that are either biodegradable or made from renewable sources a clear recipe for confusion. We will not use this term. Rather, we will use the term biobased plastics to refer to plastics made from biological sources (typically plants). The plastics may be made directly by biological organisms (e.g., polyhydroxyalkanoates) or by chemical polymerization of monomers made from such sources (e.g., polylactide). Plastics may also be partially biobased (such as the CocaCola PlantBottle made from PET that is partially biobased). 

In this section we will discuss a number of the major or emerging biobased plastics that have applications in packaging. 

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Shen L, Haufe J, Patel MK (2009) Product overview and market projection of emerging biobased plastics (PRO-BIP 2009). EPNOE, Paris, http //www.epnoe.eu/content/download/ 7670/109501/file/PROBIP2009%20Final%20June%202009.pdf... 

This third edition fixes some of the errors that, despite our best efforts, found their way into the previous editions. Unfortunately, we re sure that we have still not found them all We have expanded and updated the discussion of biobased plastics such as PLA and PHA, plastics recycling, life cycle assessment, and a variety of other topics. 

There continue to be efforts to develop additional biobased plastics. Generally these are produced by conventional polymerization methods from biologically derived monomers (usually produced by fermentation from starch, sugar, or cellulose). And, the resulting plastics are most often not biodegradable. 

Many of these new plastics are in the polyester family. One that is getting attention is PEF, polyethylene furanoate. Avantium opened a PEE pilot plant in the Netherlands in 2011. PEF reportedly is similar to PET in performance, but is 100% biobased [10]. Polybutylene terephthalate (PBT) is available as a partially biobased plastic, from biobased 1,4-butanediol and petro-based terephthalic acid. Polybutylene succinate (PBS) is similarly made from biobased succinic acid and petro-based terephthalic acid. Poly(trimethylene terephthalate) (PTT) can be made from biobased 1,3-propanediol with, again, petro-based terephthalic acid. 

There has also been increased interest in the use of biobased materials, which may or may not be biodegradable. What are the main advantages and disadvantages of the use of biobased plastics ... 

BEN 10] Benaniba M.T., Massardier-Nageotie V., Evaluation effects of biobased plasticizer on the thermal, mechanical, dynamical mechanical properties, and permanence of plasticized PVC , Journal of Applied Polymer Science, vol. 118, no. 6, pp. 3499-3508, 15 December 2010. 

Table 8.3 Overview of other biobased plastics on the market according to [16],...

Biobased plastics are rightly regarded as a technology, which offers multiple perspectives to both industry and society. Never before has a class of materials based on principles of sustainability and having the goal of producing in closed loops been so obviously realized from the outset... 

COPA, the Committee of Agricultural Organisation in the European Union and COG EGA, the General Committee for the Agricultural Co-operation in the European Union have estimated the potential of biobased plastics in different sectors of the European economy in 2001 [17]. They forecasted a potential of 2 milUon tons per year, split to the following sectors as shown in Table 8.4. 

Table 8.4 Forecasted potential of biobased plastics in Europe [17].

Philp JC, Ritchie RJ, Guy K. Biobased plastics in a bioeconomy. Trends Biotechnol 2013 31 (2) 65-67. 

Reddy MM, Vivekanandhan S, Misra M, Bhatia SK, Mohanty AK. Biobased plastics and bionanocomposites current status and future opportunities. Prog Polym Sci 2013 38... 

More recently, interest in life-cycle assessment is being superseded to some degree by interest in development of sustainable systems. Sustainability is perhaps a more useful concept than life-cycle assessment, since it avoids some of the complexities of determining, for example, whether a amount of air emission A is better or worse than y amount of water emission B. Rather, the focus is on whether goods are being produced, used, and disposed of in a manner that allows us to continue to produce and use them into the indefinite future. One intersection of sustainable development with plastics is increased interest in biobased plastics, since these likely come from renewable feedstocks, with potential for sustainable production, rather than from nonrenewable fossil fuels. Of course, recycling may also help make production systems more sustainable. 

Other Polysaccharides. Some biodegradable or biobased plastics are made by starting with cellulose and modifying it to make it thermoplastic. For example, the Japanese company Ebara Jitsugyo, Ltd. (El CO), manufactures several products based on cellulose acetate that are claimed to be biodegradable. ... 

Brochures, reports and publications on specific areas such as on Biobased Chemicals Bio-based Chemicals -Value Added Products from Biorefineries , Green Building Blocks for Biobased Plastics and Biofuel-driven biorefineries and A Selection of the most Promising Biorefinery Concepts to produce Large Volumes of Road Transportation Biofuels by 2025 . ... 

According to Gustavsson et al. food commodities can be grouped into cereals roots and tubers fruits and vegetables meat, fish and seafood milk and egg. Examples for substantial products are products derived from paper, timber, particle boards, biobased plastics, biobased chemicals and for energy carriers steam, biogases, biodiesel, bioethanol. 

Ramires EC, Megiatto JD Jr, Gardrat C, Castellan A, Erollini E (2010) Biobased composites from glyoxal-phenolic resins and sisal fibers. Bioresour Technol 101 1998-2006 Reddy MM, Vivekanandhan S, Misra M, Bhatia SK, Mohanty AK (2013) Biobased plastics and bionanocomposites current status and future opportunities. Prog Polym Sci 38 1653-1689 Rojas OJ, Montero GA, Habibi Y (2009) Electrospun nanocomposites from polystyrene loaded with cellulose nanowhiskers. J Appl Polym Sci 113 927-935 Rowell RM (2012a) Chemical modification of wood to produce stable and durable composites. Cell Chem Technol 46 443 148... 

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