Proteins bioplastics based

Among the different categories of biodegradable plastics obtained from agropolymers, both starch/polyesters blends and microbial biodegradable plastics satisfied the majority of requirements asked by the plastic packaging industries (material qualities, processability, performances, etc.). Other bioplastics based on natural polysaccharides or proteins are mainly interesting for their low cost but their non-reproduetive quality and lower performances are still a handicap. 

Protein-based materials have also been abundantly discussed in other publications [ZHA08], The next section of this chapter is, therefore, primarily oriented toward one example of an agropolymer starch. World production of starch-based materials for bioplastic applications is far from negligible. Put differently, it is greater than or ecpral to that of PLA. 

The main natural biomaterials for bioplastics are proteins, cellulose derivatives, alginates, pectins, starch and other polysaccharides. The solubility in water of the polysaccharide film is advantageous in situations where the film is consumed with the product, resulting in little change in the food s sensory properties. " Edible films based on proteins, polysaccharides or lipids minimize special care with the final package and increase food quality. ... 

Since the 1980s, the number of academic research programmes, and industrial research and development projects on protein-based bioplastics has increased exponentially, as a result of the present interest in using some field crops for renewable and biodegradable materials for nonfood applications, and also in order to explore the unique specific... 

Thus, protein-based bioplastics can be obtained by extrusion, calendering, extrusion blow moulding, injection and thermoforming processes. These thermoplastic processes are derived from synthetic material production processes. 

There are several available reports focusing on the NFR soybean protein-based composites for example, Liu et al. [46] evaluated the mechanical properties of grass-reinforced soy-based bioplastic, while Lodha and Netravah [47] evaluated the interfacial strength for ramie fiber-reinforced soy protein isolate (SPI). It must be noted, however, that the long-term performance of soy proteins is Hmited because of their high sensitivity to moisture as a result of the presence of amine, amide, carboxyl, and hydroxyl groups. To reduce their hygroscopicity, the soy proteins are cross-Hnked with aldehydes such as formaldehyde. 

W., Misra, M., Mulukutla, P.V., and Drzal, L.T. (2005) Injection molded biocomposites from soy protein based bioplastic and short industrial hemp fiber./. Polym. Environ., 13, 279-283. 

Guilbert, S. (2002) Protein-based Bio-Plastics formulation, thermoplastic processing and main applications International Congress Trade Show The Industrial Applications of Bioplastics, 3rd, 4th and 5th February Gunatillake P.A. and Adhikari R. (2003) Biodegradable synthetic polymers for tissue engineering , European Cells and Materials, 5, 1-16. 

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