abstract |
Compositions for scavenging oxygen are disclosed. These compositions comprise condensation copolymers comprising predominantly polyester segments and an oxygen scavenging amount of polyolefin oligomer segments. The polyester segments comprise segments derived from typical bottling and packaging polyesters such as PET and PEN. The copolymers are preferably formed by transesterification during reactive extrusion and typically comprise about 0.5 to about 12 wt % of polyolefin oligomer segments. The copolycondensates are capable of absorbing at least 0.4 cc of oxygen per gram of copolymer in the solid state at ambient temperatures and are typically used as layers in films, liners, cups, wraps, bottles, etc. Use of these oxygen scavenging compositions in bottles provides a clear and rigid bottle similar in appearance to unmodified polyester bottles. In a series of preferred embodiments, bottles fabricated with the oxygen scavenging copolycondensates of this invention are over 99.4 wt % polyester and suitable for recycle with other polyester bottles. |