Polymer compositions for the production of articles of biodegradable plastics material and methods for their preparation
US5334634A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 13, 1991 |
| Grant date | Aug 2, 1994 |
| Priority date | — |
| Expiry date | Aug 13, 2011 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08L2205/03
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
A polymer composition usable for the production of articles of biodegradable plastics material includes an ethylene/vinyl alcohol copolymer and destructured starch. Preferably, the composition is obtainable by mixing the ethylene/vinyl alcohol copolymer, in a heated extruder, with a starch component constituted by a destructured starch composition produced beforehand by mixing starch with a high-boiling plasticizer, such as glycerine and a destructuring agent, preferably constituted by urea, in an extruder. Alternatively, the composition can be obtained by mixing the ethylene/vinyl alcohol copolymer with starch and a plasticizer in an extruder, with water added as appropriate and possibly with a suitable destructuring agent. The composition is particularly useful for the production of films with good resistance to perforation and tearing and molded articles with improved mechanical strength. The products made from this composition are also good oxygen and carbon dioxide barriers.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.