Hot-fillable containers containing PET/PEN copolymers and blends

Bottles and containers made of PET are not suitable for hot filling since the limiting upper‐use temperature of this polymer is about 85°C. In the present study the properties and performance of bottles made from copolymers and blends of PET containing NDC groups and manufactured by the Injection Stretch Blow Molding (ISBM) process were investigated. These compositions possess advanced properties and can be used up to 95°C. The properties of these bottles were found to depend on their composition and microstructure. The glass transition temperature, the degree of crystallinity and the induced strains that were measured by differential scanning calorimetry and differential mechanical thermal analysis are reported. It was concluded that NDC‐containing PET based copolymers and blends could be processed by a one‐stage ISBM process into containers of improved properties and hot‐filling capabilities. Polym. Eng. Sci. 44:1670–1675, 2004. © 2004 Society of Plastics Engineers.