Polyester resin molding compositions and molded articles formed of the same
US5115004A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 14, 1991 |
| Grant date | May 19, 1992 |
| Priority date | — |
| Expiry date | Aug 14, 2011 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08L67/02
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
Polyester resin molding compositions exhibiting exceptional low temperature physical properties (i.e., flexibility and toughness) and satisfactory mold-release properties include a melt-blend of a polyester base resin (preferably one which predominantly contains polybutylene terephthalate units), a polyester elastomer (preferably a copolyester having hard and soft segments), and a mold-release effective amount of a sorbitan ester (preferably an ester reaction product of a sorbitan with fatty acid having at least 12 carbon atoms). The sorbitan ester most preferably has a hydroxyl value of between 50 to 400, exclusive, so that blooming during injection molding operations (e.g., a predrying stage) is minimized (if not eliminated entirely). Molded articles formed of the compositions of this invention may be used in a variety of applications, for example, as parts for the automotive and/or electronics industries.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.