Thermoplastic starch utilizing a biodegradable polymer as melting aid

US6472497B2 · kind B2 · utility

Assignee

• BIO-TEC BIOLOGISCHE NATURVERPACKUNGEN GMBH & CO. KG · DE

Inventors

• Jurgen Loercks · Rees, DE
• Winfried Pommeranz · Enger, DE
• Harald Schmidt · Nideggen, DE
• Ralf Timmermann · Krefeld, DE
• Ernst Grigat
• Wolfgang Schulz-Schlitte · Langenfeld, DE

Key dates

• Filing date: Apr 30, 2001
• Grant date: Oct 29, 2002
• Expiry date: Apr 30, 2021

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C08L2201/06
• WIPO field: Other special machines
• WIPO sector: Mechanical engineering

Abstract

Thermoplastic starch compositions formed by converting native starch or starch derivatives into thermoplastic starch by at least one hydrophobic biodegradable polymer that functions as a plasticizer for starch. The hydrophobic biodegradable polymer may be a polymer selected from the following list: an aliphatic polyester, a copolyester with aliphatic and aromatic blocks, a polyester amide, a polyester urethane, a polyethylene oxide polymer and/or a polyglycol, and/or mixtures of these. When the starch, such as in particular native starch or derivatives thereof, is mixed in the melt with the hydrophobic biodegradable polymer as a plasticizer or swelling agent, to homogenize the mixture, the water content is reduced to less than about 5% by weight based on the weight of the mixture.