| abstract |
Polyester resins having low oxygen permeability are useful as packaging materials, such as bottles, cans, film wraps, and the like. This invention discloses a process for the synthesis of such polyester resins having low oxygen permeability by a solid state polymerization technique. In this technique a polyethylene terephthalate prepolymer and a polyethylene isophthalate prepolymer are simultaneously solid state polymerized together to yield such a high barrier resin. |