Patent ID: 6288131
Filing Date: 2001-09-11
Classification: B29C,C08G,C08J,Y02W

Abstract:
A process for making a polyethylene terephthalate (PET) material, comprising the steps of:collecting diverse PET material having a wide distribution of intrinsic viscosity (IV) values, primarily within the range of 0.60 to 0.80 dl/g, but as high as 0.90 dl/g, and wherein the difference in said IV values of said collected PET material is at least 0.05 dl/g;co-mingling said collected PET material and reforming said co-mingled PET material into a single heterogeneous IV batch mixture of PET material comprised substantially of a plurality of non-uniform flake-like and chunklike pieces; anddirectly subjecting said single heterogeneous IV batch mixture of PET material to solid state polymerization (SSP) so as to form a heterogeneous PET material having an average IV value of at least 0.85 dl/g.