Biodegradable polymeric mixtures based on thermoplastic starch

US6235815A · kind A · 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: Dec 18, 1998
• Grant date: May 22, 2001
• Expiry date: Dec 18, 2018

Classification

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

Abstract

For converting native starch or starch derivatives into thermoplastic starch, added to the starch is at least one hydrophobic biodegradable polymer. This hydrophobic biodegradable polymer, which serves as a plasticizer or swelling agent, 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 <1% by weight based on the weight of the mixture.