Passive barrier layer placement within carbonated beverage container wall to improve shelf-life

A preform configured to form a carbonated beverage container, the preform comprising:

• a finish defining an opening;
• a body portion extending from the finish;
• a bottom portion at an end of the preform opposite to the finish, a longitudinal axis of the preform extends through an axial center of the bottom portion;
• a base layer included with the body portion and the bottom portion, the base layer has an inner portion with an inner surface at a carbonated product side of the preform, and an outer portion with an outer surface at an outer bottle side of the preform;
• and
• a passive CO2 barrier layer between the inner portion and the outer portion of the base layer, the passive CO2 barrier layer extending along the body portion to the bottom portion, and across the bottom portion, the passive CO2 barrier layer is arranged closer to the inner surface than the outer surface;
• wherein:
• the passive CO2 barrier layer is blended with polyethylene terephthalate (PET);
• the passive CO2 barrier layer includes polyglycolic acid (PGA) at about 10 wt. % of the base layer and the passive CO2 barrier layer combined;
• the passive CO2 barrier layer decreases in thickness as the passive CO2 barrier layer extends along the bottom portion such that the passive CO2 barrier layer is most thin at the axial center of the bottom portion;
• the container is configured to be filled at a gas fill volume of 1.5 g.v. resulting in 19% CO2 loss over 40 weeks or less of shelf life;
• the carbonated beverage container formed from the preform includes a container wall having the passive CO2 barrier layer between the inner portion and the outer portion of the base layer, the passive CO2 barrier layer is 5%-40% of an overall thickness of the container wall;
• and
• a midpoint of the passive CO2 barrier layer is spaced apart from the inner surface of the base layer by 20-40% of the overall thickness of the container wall.