530 Novel food packaging techniques Table 24.1 Properties of polymers used as packaging materials Polymer Tensile strength Tensile modulus Max use temperature LDPE 0.140.19 HDPE 2.84.1 41.3-51.7 PA 6 1.2-28 PLA Table 24. 1 gives some properties of polymers used in packaging materials Among the biodegradable polymers PLA seems to be the polymer that can compete in terms of mechanical properties with conventional polymers. The drawback here is the low Tg of PLA. The main players in the biodegradable polymer market are shown in Table 4.2. Despite the slow entry into of use of biodegradables in food packaging, some trends are visibly shifting towards sustainable chemistry and green plastics being applied in niche markets. Most of the efforts these days seem to be focused on foamed products for food 24.5. 2 Starch based foams in food packaging The use of foamed polymer packaging, for example, polystyrene(PS) clamshells, by prominent users such as Mc Donald's Restaurants has recently decreased significantly because of perceived environmental disadvantages Table 24.2 Main players in biodegradable polymers and their trade names Material Supplier Trade name Starch based Novamont MaterI Starch based Biotec Thermoplastic starch Avebe Thermoplastic starch National Starch Ecofoam ( Novamont licensee) Environal Polylactide/PLA argil Dow Nature Works pla Polylactide/PLA Polylactide/PLA Polylactide/PLA Galactic Galactic (Co)polyester BASE Ecoflex (Co)polyest Eastman Chemical Eastar Bio Du por Biomax Co)polyester Showa Highpolymer Bionolle Polycaprolactone Union Carbide Polycaprolactone Solvay CAPTable 24.1 gives some properties of polymers used in packaging materials.19 Among the biodegradable polymers PLA seems to be the polymer that can compete in terms of mechanical properties with conventional polymers. The drawback here is the low Tg of PLA.20 The main players in the biodegradable polymer market are shown in Table 4.2. Despite the slow entry into of use of biodegradables in food packaging, some trends are visibly shifting towards sustainable chemistry and green plastics being applied in niche markets. Most of the efforts these days seem to be focused on foamed products for food packaging. 24.5.2 Starch based foams in food packaging The use of foamed polymer packaging, for example, polystyrene (PS) clamshells, by prominent users such as McDonald’s Restaurants has recently decreased significantly because of perceived environmental disadvantages. Table 24.1 Properties of polymers used as packaging materials Polymer Tensile strength Tensile modulus Max. use MPa GPa temperature ºC LDPE 6.2–17.2 0.14–0.19 65 HDPE 20–37.2 121 PET 68.9 2.8–4.1 204 PS 41.3–51.7 3.1 78 PA 6 62–82.7 1.2–2.8 – PP 33–37.9 1.1–1.5 121 PLA 40–60 3–4 50–60 Table 24.2 Main players in biodegradable polymers and their trade names Material Supplier Trade name Starch based Novamont MaterBi Starch based Biotec Bioplast Thermoplastic starch Avebe Paragon Thermoplastic starch National Starch Ecofoam (Novamont licensee) Envirofil Polylactide/PLA Cargill Dow Nature Works PLA Polylactide/PLA Mitsui Lacea Polylactide/PLA Hycail Polylactide/PLA Galactic Galactic (Co)polyester BASF Ecoflex (Co)polyester Eastman Chemical Eastar Bio (Co)polyester Du Pont Biomax (Co)polyester Showa Highpolymer Bionolle Polycaprolactone Union Carbide Tone polymer Polycaprolactone Solvay CAPA 530 Novel food packaging techniques