| abstract |
Plastic additives which are useful as nucleating agents and which are especially useful for improving the optical properties of polymeric materials are provided. More particularly, this invention relates to certain symmetric DBS compounds comprising specific pendant groups, such as C3-C6 alkyl, C1-C6 alkoxy, phenyl, and methylenedioxy (as the combination of two available sites on the pertinent ring system), as well as wherein the individual benzylidene ring systems may be indan or tetralin. Because of the required symmetrical configuration, the pendant groups on each ring system of the dibenzylidene sorbitol compound must be located at the same positions. Such compounds may be added to or incorporated within polymer compositions which may then be utilized within, as merely examples, food or cosmetic containers and packaging. |