摘要:
Generation of acetaldehyde from a polyethylene terephthalate resin migrating to a vapor space between the contents of a container and the container closure may be controlled by the addition of acetaldehyde scavenging additives to the closure polymer or to a liner polymer in direct contact with the vapor space.
摘要:
The present invention includes novel ligands which may be utilized as part of a catalyst system. A catalyst system of the present invention is a transition metal - ligand complex. In particular, the catalyst system includes a transition metal component and a ligand component comprising a Nitrogen atom and/or functional groups comprising a Nitrogen atom, generally in the form of an imine functional group. In certain embodiments, the ligand component may further comprise a phosphorous atom. Preferred ligand components are bidentate (bind to the transition metal at two or more sites) and include a nitrogen - transition metal bond. The transition metal - ligand complex is generally cationic and associated with a weakly coordinating anion. A catalyst system of the present invention may further comprise a Lewis or Bronsted acid. The Lewis or Bronsted acid may be complexed with the ligand component of the transition metal-ligand complex.