BIODEGRADABLE THREE-LAYERED FILM

• Main Authors: AUFFERMANN, Joerg, SKUPIN, Gabriel, SINKEL, Carsten, EFFEN, Norbert, LOHMANN, Jerome, KUENKEL, Andreas, SCHLUTT, Nora, LOOS, Robert
• Format: Patent
• Language: English; French; German
• Published: 29.04.2020
• Subjects: AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F,C08G; CHEMISTRY; COMPOSITIONS BASED THEREON; COMPOSITIONS OF MACROMOLECULAR COMPOUNDS; GENERAL PROCESSES OF COMPOUNDING; LAYERED PRODUCTS; LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT ORNON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM; METALLURGY; ORGANIC MACROMOLECULAR COMPOUNDS; PERFORMING OPERATIONS; THEIR PREPARATION OR CHEMICAL WORKING-UP; TRANSPORTING; WORKING-UP

The invention relates to a biodegradable, 8- to 20-μm-thick three-layer polyester film having a layer structure A/B/C or preferably A/B/A, wherein the two outer layers (A) or (A, C) are composed of: Ai) 55 to 99.99 wt.%, relative to the polyester mixture of the outer layers, of a polyester selected from the group consisting of: polybutylensebacat-co-terephthalate, polybutylensebacat-co-adipat-co-terephthalats, polybutylensebacat-co- succinat-co-terephthalats or mixtures thereof or a mixture of Polybutylensebacat-co-terephthalate and Polybutylenadipat-co-terephthalate; Aii) 0.01 to 5 wt.%, relative to the polyester mixture of the outer layers, at least one additive selected from the group consisting of: a wax, a softener, a nucleating agent, an anti-fog agent, a filler and an antiblocking agent; and Aiii) 0 to 44.99 wt.%, relative to the polyester mixture of the outer layers, of an additional biodegradable polymer selected from the group consisting of: polyactic acid (PLA), polycaprolactone (PCL), polyhydroxyalkanoate, polypropylene carbonate (PPC) or polyester, produced from aliphatic dicarboxylic acids and an aliphatic didydroxy compound; and the center layer B composed of: Bai) 40 to 75 wt.%, relative to the mixture of the center layer, of a biodegradable, alphatic-aromatic polyester; Baii) 25 to 40 wt.%, relative to the mixture of the center layer, starch having a softener content of 0 to 5 wt.%, relative to the total weight of the component Baii); and Baiii) 0 to 20 wt.%, relative to the mixture of the center layer, of an additional biodegradable polymer selected from the group consisting of: polyactic acid (PLA), polycaprolactone (PCL), polyhydroxyalkanoate, polypropylene carbonate (PPC) or polyester, produced from aliphatic dicarboxylic acids and an aliphatic dihydroxy compound; or Bbi) 25 to 70 wt.% relative to the mixture of the center layer, of a biodegradable, aliphatic-aromatic polyester Bbii) 30 to 55 wt.%, relative to the mixture of the center layer, starch having a softener proportion of 5 to 35 wt.%, relative to the total weight of the component Bbii); and Bbiii) 0 to 20 wt.%, relative to the mixture of the center layer, of an additional biodegradable polymer, selected from the group consisting of: polyactic acid (PLA), polycaprolactone (PCL), polyhydroxyalkanoate, polypropylene carbonate (PPC) or polyester, produced from aliphatic dicarboxylic acids and an aliphatic dihydroxy compound.