Biodegradable polymer masterbatch, and a composition derived therefrom having improved physical properties
US8008373B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 31, 2007 |
| Grant date | Aug 30, 2011 |
| Priority date | — |
| Expiry date | Aug 7, 2029 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08L2201/06
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
A biodegradable thermoplastic polymer masterbatch composition comprising a blend of at least one biodegradable thermoplastic polymer containing high loading of a particulate filler uniformly dispersed therein. The amount of the biodegradable thermoplastic polymer is generally from about 25% to about 50% by weight and the amount of the filler is from about 75% to about 50% by weight, based upon the total amount of one biodegradable polymer and the at least one filler. The uniform dispersion of the fillers is desirably obtained by adding small particles of the filler to a melt of the biodegradable polymer and blending using high shear equipment with special screw geometry. The masterbatch composition is then physically blended with additional biodegradable thermoplastic polymer and extrusion processed into final articles such as blown and cast films, molded products, and the like. The masterbatch multi-stage approach of the present invention results in a product that has improved physical properties and lower costs over that of a one step blend of the same amount of a biodegradable thermoplastic polymer and a filler that is subsequently heat formed into a final product.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.