Method of preparing modified polyester bottle resins

A method of preparing a high molecular weight copolyester bottle resin that has excellent melt processing characteristics, comprising:

• reacting a terephthalate component and a diol component to form a modified polyethylene terephthalate, wherein
• the terephthalate component includes at least about 90 mole percent terephthalic acid,
• the diol component is present in excess of stoichiometric proportions and includes at least about 2 mole percent diol comonomer with the remainder being ethylene glycol;
• and
• the terephthalate component and the diol component together include at least 7 mole percent comonomer substitution;
• thereafter copolymerizing the modified polyethylene terephthalate in the melt phase to an intrinsic viscosity of between about 0.25 dl/g and 0.40 dl/g to thereby form a copolyester prepolymer having an average apparent crystallite size of less than 9 nm;
• thereafter forming the copolyester prepolymer into chips;
• thereafter polymerizing the copolyester prepolymer chips in the solid phase to form a high molecular weight bottle resin, wherein the bottle resin has an intrinsic viscosity of at least about 0.70 dl/g and a solid phase density of less than 1.413 g/cc;
• and
• forming the high molecular weight bottle resin into bottle preforms at a haze temperature below 260° C.

Bottle resin chips of a high molecular weight copolyester having excellent melt processing characteristics, comprising:

• about a 1:1 molar ratio of a terephthalate component and a diol component, said terephthalate component including at least about 4 mole percent diacid or diester comonomer with the remainder being terephthalic acid or dimethyl terephthalate, and said diol component including at least about 2 mole percent diol comonomer with the remainder being ethylene glycol;
• an intrinsic viscosity of at least about 0.70 dl/g;
• a solid phase density of between 1.401 and 1.413 grams/cc;
• an average apparent crystallite size of less than 9 nm;
• a haze temperature of less than about 250° C.;
• and
• wherein said bottle resin chips have an average minimum dimension of between about 1 mm and 10 mm.

Bottle resin chips of a high molecular weight copolyester having excellent melt processing characteristics, comprising:

• about a 1:1 molar ratio of a terephthalate component and a diol component, said terephthalate component including at least about 9 mole percent isophthalic acid or its dialkyl ester with the remainder being terephthalic acid or dimethyl terephthalate, and said diol component including at least about 2 mole percent diethylene glycol with the remainder being ethylene glycol;
• an intrinsic viscosity of at least about 0.80 dl/g;
• a solid phase density of between 1.390 and 1.413 grams/cc;
• an average apparent crystallite size of less than 10 nm;
• a haze temperature of less than about 240° C.;
• and
• wherein said bottle resin chips have an average minimum dimension of between about 1 mm and 10 mm.