Method of making polymer compositions containing thermoplastic starch
US6844380B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 18, 2002 |
| Grant date | Jan 18, 2005 |
| Priority date | — |
| Expiry date | Jul 25, 2023 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08L23/04
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
There is provided a method of preparing a thermoplastic starch and synthetic polymer blend, said method comprising the steps of: (a) providing a starch suspension comprising starch, water and a plasticizer, preferably glycerol; (b) obtaining a thermoplastic starch from the starch suspension by causing gelatinization and plasticization of said starch suspension by exerting heat and pressure on said starch suspension in a first extrusion unit; (c) evaporating and venting off residual water from said thermoplastic starch to obtain a substantially moisture-free thermoplastic starch; (d) obtaining a melt of a synthetic polymer or polymer blend in a second extrusion unit; and (e) combining the melt obtained from step (d) with the substantially moisture-free thermoplastic starch. Also provided are compositions of matter comprising immiscible blends of thermoplastic starches, polymers, and compatibilizers.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.